Mammalian 2 orthobornavirus (VSBV-1) is an emerging zoonotic pathogen discovered in several exotic squirrel species and associated with fatal human encephalitis. The dynamics of VSBV-1 spread and evolution in its presumed natural hosts are unknown. Here, we present the phylogeny, micro-evolution, cross-species transmission and spread of VSBV-1 at a temporal and spatial resolution within the limits of animal husbandry. The results showed that VSBV-1 can be classified into six distinct groups and that the most recent common ancestor of the known German strains emerged at least 20 years ago. We here demonstrate that the genetic diversity of the VSBV-1 groups is shaped primarily by in situ evolution and most of the amino acid changes are deleterious polymorphisms removed by purifying selection. Evidence of adaptive evolution has been found in the G and L genes which might have an influence on transmission fitness. Furthermore, there was also evidence for some form of adaptive changes in the glycoprotein which suggests that many sites might be subjected to positive pressure evolving under episodic directional selection, indicating past occurrence of positive selection. Host switching events were detected as dominant evolutionary mechanisms driving the virus-host associations. Virus spread by animal trade followed by subsequent local micro-evolution in zoos and holdings is responsible for diversifying strains. Time-resolved phylogeny indicated that Prevost’s squirrels might be the original squirrel species carrying and seeding the virus in Germany. This study provides the first insight into the ecology and micro-evolutionary dynamics of this novel viral pathogen in the captive exotic squirrel population under artificial ecological conditions  and co-housing of different squirrel species. Mammalian 2 orthobornavirus) is an emerging zoonotic pathogen discovered in 2015 as the causative agent of fatal encephalitis of three men breeding exotic variegated squirrels in eastern Germany [Sciurus variegatoides; family Sciuridae, subfamily Sciurinae) are native to Central America, Prevost’s squirrels  are natural inhabitants of Southeast Asia. Epidemiological investigations in private holdings and zoological gardens in Germany and elsewhere in Europe detected VSBV-1 infection rates of 1.5% in captive Sciurinae and 8.5% in captive Callosciurinae squirrels, including one Asian Finlayson’s squirrel  and one Asian striped squirrel  [The variegated squirrel bornavirus 1  ,5. Both iurinae) ,7. The o−1 year−1), the time to most recent common ancestor (tMRCA) under a relaxed uncorrelated lognormal clock and a flexible demographic model (Gaussian Markov Random field Bayesian Skyride). An asymmetric model with Bayesian Stochastic Search Variable selection (BSSVS) was applied to identify statistically significant transition rates between host species. The Markov Chain Monte Carlo (MCMC) chain length was set to 50 million steps sampling after every 10,000 steps. The Bayesian maximum clade credibility (MCC) trees were visualized using FigTree v1.4.4 .All currently available 26 complete coding VSBV-1 sequences with known year of detection, host, and geographical origin available in databases were used in this study . SequencNd) to synonymous (Sd) nucleotide substitutions (Nd/Sd or ω ratio) per site for the detection of sites subjected to positive or negative selection or transient (episodic) selective pressures using four codon-based ML tools  implemented in the Datamonkey web interface . We also employed aBSREL (Adaptive branch-site random effects likelihood) which uses an adaptive random effects branch-site model framework to test whether each branch has evolved under positive selection, using a procedure which infers an optimal number of rate categories per branch [http://www.cbs.dtu.dk/services/; accessed on 17 April 2021).Codon-based models of evolution in an ML framework were used to evaluate the nature of the selection pressure acting on each VSBV-1 gene. It was estimated as a ratio of non-synonymous , a haplotype network was constructed using the Minimum Spanning Network (MSN) method inferred by PopART package v1.7.2 .cytochrome b gene reconstruction using PhyML and the GTR+G model. The calculations using Jane 4 and CoRe-Pa assign event-based model with co-speciation, duplication, sorting and host switching events. Cost values must be set a priori in Jane 4, whereas CoRe-PA uses a parameter-adaptive approach to search for optimal cost values. Both methods compute minimal-cost reconstruction of the evolutionary history between hosts and viruses. For Jane 4 statistical significance was established by 500 random tip mapping permutations and 500 random parasite tree permutations with Yule beta parameter equal to −1. For Core-Pa the evaluation was done using 10,000 different event cost models. For significance evaluation, a randomization test with 1000 instances with randomized host-virus associations was performed.To study the history of a possible co-speciation of VSBV-1 and its hosts or the alternative hypothesis of host switches, we performed event-based co-phylogenetic reconciliation using CoRe-PA  and JaneThe genetic variation across the genome of VSBV-1 strains  was relaHowever, the limited number of available sequences and the lack of VSBV-1 data back to the first known human case in 2007 reduces our ability to predict previous events and virus variant circulation between holding and zoos. The detailed analysis of the German strains demonstrated that VSBV-1 forms six major groups A definedP < 0.001) and the coefficient of rate variation supported the use of a relaxed clock model. By plotting root-to-tip divergence as a function of sampling time, an accumulation of nucleotide substitutions was observed over the sampling time  detected in the glycoprotein of VSBV-1 was present in two Prevost’s squirrels (KY488723 and KY488724) and one Swinhoe’s striped squirrel (KY488727), while another positively selected AA (Lys1191Leu/Arg) detected in the polymerase was present in two Prevost’s squirrels (LT594381 and KY488724), all originating from the same holding E  in the glycoprotein which suggests that many sites in the VSBV-1 genes  identified by FUBAR and MEME may be subjected to positive pressure evolving under episodic directional selection .The conservative AA change Lyselection . Using tUsing CoRe-PA and Jane 4, we tested the hypothesis of VSBV-1/host co-speciation by using reconciliation analysis, presented along with their tanglegram depicting host-virus associations A,B. EvenThe VSBV-1 phylogeny is notable for a clustering in which the dominant groups connect viruses sampled from multiple time points from the same source A. We useThe human impact on sylvatic or semi-sylvatic ecosystems as well as the trade of wild animal species facilitates contact of (novel) pathogens with susceptible (new) hosts. Understanding the ecology and genetic driving forces that contribute to the emergence and spread of zoonotic pathogens is important for the implementation of preventive strategies. In this study, we aimed to investigate the genomic and micro-evolutionary processes of VSBV-1 that were seen during infection of multiple exotic squirrel species and humans in the artificial but exemplary situation of animal husbandry and co-housing of squirrel species which live under natural conditions on different continents. Moreover, we aimed to shed more light on the possible origin of VSBV-1 infecting exotic squirrels in German holdings by novel phylogeny constructions, co-speciation analyses, transmission rate strength calculations, and haplotype network inferences.The phylogeny constructed here showed a spatial differentiation of VSBV-1 strains that resulted in the phylogenetic clustering in the form of six distinct groups defined by the geographic place of sampling . The existence of such groups is likely the result of adaptation to the local artificial ecological conditions. Hence, the adaptation of VSBV-1 to naïve host populations in captivity can lead to the emergence of local virus strains or variants, and the most likely scenario for VSBV-1 might be enzootic maintenance (in situ evolution). This assumption is further supported by the presence of some fixed AA residues involved in the formation of these six distinct groups defined by their geographic origin.The overall low ratio of non-synonymous to synonymous substitutions indicates that most AA changes are deleterious polymorphisms removed by purifying selection, likely as results of genetic drift. We found strong evidence of adaptive evolution only at codon 238 of the G gene and at codon 1191 of the L gene. Although the function of these residues remains to be determined, mutations in the G protein and/or L protein (polymerase) have exhibited enhanced neurovirulence in the related Borna Disease virus 1 (BoDV-1) in adult and newborn Lewis rats . In a reVSBV-1 infected captive exotic squirrel species of the Sciurinae and Callosciurinae subfamilies were shown to be asymptomatic, thus displaying characteristics of natural reservoir hosts ,5. The fBy co-phylogenetic reconciliation analysis, host switching was detected as the dominant mechanism driving the virus-host associations during animal trade and co-housing of different species in captivity. No hints for a co-speciation were found. When analyzed by host switching, both squirrel inter-genus and intra-genus transmissions have occurred. This suggests that VSBV-1 may switch its hosts (by spill-over infections) if the environmental conditionals are favorable, such as during co-housing or by contact to human caretakers, apparently without preferential transmission between closely or more distantly related host species. Our results do not exclude a possible co-speciation of VSBV-1 and different exotic squirrels or other host species in the wild. Field studies for the presence of VSBV-1 in wild exotic squirrel populations are therefore still essential to resolve the question of the virus’ natural host animal range and its geographic origin. This is underlined by recent investigations which showed that the animal trade to Germany was mainly fueled by a squirrel farm in Central America where Prevost’s squirrels were kept beside variegated squirrels . Thus, vOur analysis only represents a snapshot into the last evolutionary events identified and as such does not represent the complete evolutionary history of VSBV-1. It should also be noted that such events are dependent on the relationships observed in the reconstructed phylogeny trees and could appear differently once more VSBV-1 strains are found and compared with each other.Taking advantage of the artificial circumstances of animal husbandry, we were able to gain insights into adaptive and other micro-evolutionary processes in different exotic squirrel hosts that form the basis for future studies on the ecology and evolution of this zoonotic emerging viral pathogen under natural conditions. The limited number of available VSBV-1 sequences and the lack of virus data from other European countries and other continents reduce our ability to infer the spatio-temporal pattern of the virus’ spread and emergence, and thus the evolutionary history of VSBV-1.


This paper presents an efficiency assessment of social distancing as an internationally adopted measure to tackle the COVID-19 pandemic in 2020. The simple framework adopted for the assessment accounts for two kinds of costs that a society may bear in a pandemic. The first is welfare loss due to infection and its consequences, and the second is welfare loss resulting from a slowdown in economic transactions. We call the first infection costs, and the second economic costs, for convenience in the paper. Efficient social distancing should minimize the sum of these costs. Infection costs are likely to decrease with social distancing at a decreasing rate as intensified social distancing eases pressure on scarce resources for intensive care. Economic costs on the other hand are likely to increase at an increasing rate as extreme slowdown in economic life may entail job losses and business failures. The resulting U-shaped total costs curve implies parity between infection costs and economic costs as a necessary condition for efficiency. In a simplified implementation of the framework, we approximate infection costs by the value of  lives lost, and economic costs by the gap between the actual gross domestic product (GDP) in 2020 and the potential GDP as predicted by the within-country growth trend during the preceding decade. The results for 158 countries suggest that the global community perhaps reacted with overly strict social distancing measures. The results for the subgroup of high-income countries, however, suggest that these countries were more successful in maintaining the parity between infection and economic costs. The COVID-19 pandemic has claimed more than 5.2 million lives as of the end of November 2021. Economic consequences have also been devastating. The global gross domestic product (GDP) recorded a 3.5% contraction in 2020, and while economic activities have regained some momentum in 2021, the projection for the global GDP in 2021 remains below the pre-pandemic levels across the regions ,5. WhileThis paper presents a simple and practical conceptual framework for assessing efficiency in the implementation of social distancing across the countries. The framework recognizes that efficient social distancing should minimize the sum of two distinct costs a society may bear in a pandemic: first, costs due to infection by the virus (infection costs), and second, costs due to the potential slowdown in economic transactions (economic costs). Social distancing will reduce infection costs, while raising economic costs. Infection costs are likely to decrease with social distancing at a decreasing rate as intensified social distancing eases pressure on limited resources for intensive care . Due to Rigorous measurement of infection and economic costs is not an easy task . In thisOur motivation for choosing the simplifying approximations is chiefly practical, as we have no clear methods to estimate the omitted items in a credible and comparable manner across the countries in the world. In the case of the infection costs, however, we believe that our approximation is likely to capture more or less satisfactorily the true extent of the costs, as the value of lives lost will dwarf the other items. We concede that the extent of the underestimation is likely to be more substantial in the approximation we propose for the economic costs. We will discuss the implication of this observation in the discussion of the results.We followed the recommendation by Viscusi and Masterman  to estimWe have already noted that infection costs should be equal to economic costs, if social distancing is to be efficient and total costs are minimized. Thus, the ratio of infection costs over economic costs should be equal to 1 with efficient social distancing. The value of the ratio over 1 means that infection costs outweigh economic costs, and that social distancing is insufficient in view of efficiency. In the context of The actual range of the ratio of infection costs over economic costs is widely spread on both sides of the critical value of 1. For our sample of 158 countries, both the mean and the median of the ratios are significantly below 1, suggesting that the vast majority of countries in the global community practiced overly restrictive social distancing. For 34 countries in the sample with per capita income over USD 20,000, however, we cannot reject the null hypothesis that the mean or the median of the ratio is equal to 1.The rest of the paper proceeds as follows. Infection costs comprise costs for medical treatment, value of labor lost by the infected during treatment and recovery, reduction in welfare due to long COVID, and most importantly, value of lives lost. Our “ballpark” estimation focuses on the value of lives lost, ignoring the remaining items. This decision was chiefly forced by the difficulty in estimation for a large number of countries, but may be justified in that the value of lives lost most probably dominates the remaining items by an order of magnitude.To measure the value of lives lost to the pandemic, we rely on the concept of the value of a statistical life (VSL). The VSL is a measure of life’s value derived from the tradeoff rate between fatality risk and money, often observed through choices in product and labor market contexts . Since tIn the equation, elasticity is a positive parameter capturing the empirical pattern among existing VSL estimates, showing higher VSL values for more affluent societies. Following the recommendation by Viscusi and Masterman , we usedEstimating economic costs poses an even greater challenge. We estimated economic costs through the difference between the actual 2020 GDP and the predicted 2020 GDP estimated using the average annual growth rate during the previous decade. We are aware that this approximation clearly understates the true value, as it ignores welfare loss due to negligence in the care of other diseases, loss in psychological wellbeing due to imposed isolation, and adverse consequences for disruption in the investment for human capital. While we lack a credible method to estimate the value of the omitted items across a large number of countries, country case studies indicate that the welfare reduction implied by these items is indeed substantial ,13,14,15Using data on GDP and COVID-19 deaths sourced, respectively, from the World Bank and the World Health Organization, we have calculated infection costs and economic costs per capita. The summary statistics for these and other related variables are presented in In t-test is the ratio of infection costs over economic costs. If the ratio is at 1 or near 1, we may decide the country was efficient in social distancing in the sense of minimizing the sum of infection and economic costs. Values of the ratio far away from 1 signify failure of efficient social distancing, either overly strict (the ratio much lower than one) or overly lax (the ratio much larger than one). Therefore, we present the null and alternative hypotheses as follows:We may formally test how successful countries are in efficient practice of social distancing. The variable used in the one-sample t-tests. At conventional levels of significance of either 5% or 1%, we strongly reject the null hypothesis. As a matter of fact, the p-value from the test is less than 0.0001. The results from the one-sample t-test for the high-income subsample are also presented in See We have applied a simple framework with fairly light data requirements and assessed efficiency in the global practice of social distancing, and found that the intensity in social distancing was overly strict in a majority of countries during the first year of the pandemic. We used the annual timeframe to compare infection and economic costs. In countries where GDP estimates are expediently made available at a higher frequency, it might be possible to put the paper’s framework to a practical, “ballpark”-style assessment of the social distancing practice, for instance on a quarterly basis. An ideal and more rigorous assessment of efficiency in social distancing as a response to the COVID-19 pandemic would require a set of elaborate models and a range of reliable data. For instance, Thunström and others [For the whole sample, it was obvious that the vast majority of countries in the world were erring on the overly strict side of the balance, that is, on the right-hand side of the optimal distancing level, Assuming no measurement error, parity between infection costs and economic costs should be desired in the normative sense, as a society struggles to cope with the pandemic at the lowest possible costs. We surmise at the same time that there might also be a positive tendency for the ratio to converge to one over time. This would be the case, for instance, if the political processes in a given society are successful in incorporating diverse interests and voices among the public in an efficient manner. This observation suggests two natural extensions to the study that this paper reports: When the GDP data become available for 2021, we should be able to check whether countries do migrate closer to the 45-degree line in a chart as in


Aedes aegypti, the Orlando strain, after Sindbis virus infection. Greater titer variation was observed after oral versus intrathoracic infection, suggesting that the midgut barrier contributes to titer variability. Among the other factors tested, only the length of the incubation period affected the degree of titer variability, while virus strain, mosquito strain, mosquito age, mosquito weight, amount of blood ingested, and virus concentration in the blood meal had no discernible effect. We also observed differences in culture adaptability and in the ability to orally infect mosquitoes between virus populations obtained from low and high titer mosquitoes, suggesting that founder effects may affect the virus titer in individual mosquitoes, although other explanations also remain possible.The mechanisms involved in determining arbovirus vector competence, or the ability of an arbovirus to infect and be transmitted by an arthropod vector, are still incompletely understood. It is well known that vector competence for a particular arbovirus can vary widely among different populations of a mosquito species, which is generally attributed to genetic differences between populations. What is less understood is the considerable variability  that is routinely observed in the virus titer between individual mosquitoes in a single experiment, even in mosquitoes from highly inbred lines. This extreme degree of variation in the virus titer between individual mosquitoes has been largely ignored in past studies. We investigated which biological factors can affect titer variation between individual mosquitoes of a laboratory strain of  Arboviral diseases account for approximately 17% of all infectious diseases globally and approximately 40,000 deaths each year, making them a great public health concern [SINV is classified as an emerging pathogen that is mainly reported in northern Europe and southern Africa . In SwedArboviral diseases continue to persist due to the existence of the vector mosquitoes in endemic areas  and alsoAe. aegypti from field-caught populations after infection with DENV and correlated differentially expressed genes with the levels of viral RNA [A major limiting factor hindering the effort to develop new vector control strategies is the lack of a comprehensive understanding of what determines vector competence. Many studies have identified biological factors that contribute to differences in mosquito susceptibility to arbovirus infection, such as mosquito age , virus siral RNA , resultiAe. aegypti, a laboratory strain that was first established around 1940 and has been highly inbred since that time. Although precise husbandry records are not available, it has been reported that occasional outcrossing of Orlando with wild Ae. aegypti populations was performed up to 1992 [In this study, we used SINV as a model arbovirus to investigate the contributions of several biological factors to variation in virus titer using the Orlando strain of  to 1992 . We were2. C6/36 cells were maintained in Leibovitz’s L-15 media (Gibco) plus 10% FBS at 27 °C. Aag2 cells were maintained in Schneider’s media (Gibco) plus 10% FBS at 27 °C.BHK-21 cells were propagated in Dulbecco modified Eagle medium  supplemented with 10% fetal bovine serum  at 37 °C with 5% COAe. aegypti mosquito strains Orlando  and Rex-D  were reared at 27 °C, 80% humidity on a 12 h light/12 h dark cycle. Ae. aegypti eggs were hatched in water containing brain heart infusion media (BHI) for 2 days to produce mosquito larvae. Mosquito larvae were separated into pans (each pan containing approximately 100 larvae) with a small amount of BHI and ground fish meal added. Larvae metamorphosized into pupae within 5–7 days. The pupae were transferred into pupa cups and transferred into mosquito cages. Adult mosquitoes emerged beginning at around 2 days after transfer. Adults were allowed to feed on raisins and water before and after blood feeding. All mosquito experiments were performed in an arthropod containment level 2 insectary at Kansas State University.5 cells BHK21 cells were plated in each well of 6-well plates in serum-free opti-MEM media (Gibco) and allowed to attach for 2 h. Six μL of Lipofectamine 3000 (Thermo Fisher), 100 μL opti-MEM, and 10 μL of 13.5 ng/ul viral RNA were mixed and allowed to sit for 5 min. After incubation, 900 μL of opti-MEM was then added to the tube containing the mixture and mixed with the seeded BHK-21 cells [50) assay in BHK-21 cells, as described below. Virus stocks used in this study were thawed only once before use.The MRE-16 and TE infectious clones p5′dsMRE16ic and pTE5′2J, respectively, were obtained from Ken Olson (Colorado State University), and their construction was described ,23. The 21 cells . The BHK4 BHK-21 cells were seeded in each well of 96-well tissue culture plates. The DMEM media was supplemented with 15 μg/mL of penicillin/streptomycin . Frozen mosquito samples were thawed on ice and centrifuged at 4 °C for 3 min at 15,000× g to remove debris, while samples obtained from tissue culture cells were thawed on ice without centrifugation. Serial dilutions of each sample were added to 5 duplicate wells of BHK-21 cells. The plates were scored for cytopathic effects after 5 days, and the proportion of infected wells was used to calculate TCID50/mL values [50/mL values were multiplied by 0.69 to obtain the PFU/mL values.A total of 1 × 10L values . The TCI50 assay.Newly emerged adult female mosquitoes were allowed to feed on raisins and water ad libitum. At 2 days post-emergence, raisins were removed but not water, and mosquitoes were starved for 1 day. For the mosquito age experiment, mosquitoes ages 3, 5, 7, 14, and 21 days post-emergence were used, and they were starved a day before they turned the required age needed for the experiment. The mosquitoes were then separated into smaller containers. P2 virus stocks were mixed with defibrinated sheep blood in a ratio of 1:1 and fed to the mosquitoes for 1 h using a Hemotek membrane feeder  covered with Parafilm. For the viral concentration experiment, the P2 virus stock was diluted with Leibovitz’s medium to the desired concentration. The mosquitoes were briefly cold-shocked at 4 °C, and then fully engorged females were separated from the remaining mosquitoes. Fed females were subsequently maintained on raisins and water for 5 days post-blood meal (PBM) before dissecting. For the incubation period experiment, mosquitoes were harvested at 5, 10, and 15 days PBM. At the appropriate time points, mosquitoes were killed by freezing at −20 °C, and the killed mosquitoes were placed in 200 μL DMEM plus 10% FBS and homogenized in 1.5-mL microcentrifuge tubes using disposable plastic pestles. The samples were frozen at −80 °C until the titers were determined by TCIDNewly emerged adult female mosquitoes were fed on raisins and water until they were 3, 7, or 10 days old. These female mosquitoes were cold anesthetized and injected with one pulse of 69 nl of MRE-16 P2 virus stock and diluted with DMEM plus 10% FBS so that each mosquito received a dose of 10 PFU, using a Nanoject II injector . After recovering, the mosquitoes were maintained on raisins and water for 5 days, after which they were harvested and titered as described above.8 PFU/mL), medium titer (2.9 × 106 PFU/mL), or low titer (2.1 × 104 PFU/mL), or MRE-16 P2 stock virus were used to infect C6/36 and Aag2 cells at a multiplicity of infection (MOI) of 0.1 in a 6 well plate. The diluent used for high and medium titer stocks was prepared by homogenizing two female mosquitoes in 900 µl of Leibovitz’s (for infecting C6/36 cells) or Schneider’s (for infecting Aag2 cells) medium. After a 1 h absorption period, 2 mL of Leibovitz’s or Schneider’s medium containing 10% FBS was added into each well. At 0, 1, 2, 3, 4, and 5 days post-infection, 200 μL of cell culture medium containing virus were collected and frozen at -80 °C until ready for TCID50 assay.Virus that was obtained from pools of five mosquitoes that exhibited high titer  was used rather than standard deviation to measure variation within each set of data.GraphPad Prism 5 software was used for statistical analysis utilizing Mann–Whitney U, Kruskal–Wallis, Fisher’s exact, two-way ANOVA , and Pearson’s chi-square tests. Dunn’s test was used for post hoc multiple-comparison analysis for Kruskal–Wallis tests that showed significance difference. A 9 PFU/mL or were injected with 10 PFU of passage 2 (P2) virus derived from an infectious clone of the MRE-16 strain of SINV, and then the virus titer in whole mosquitoes was determined by TCID50 assay at 5 days after virus exposure. The results of this experiment revealed a significantly higher median titer in mosquitoes at this time point after oral infection compared to intrathoracic infection . More interestingly, however, there was greater variation in the individual titers of orally infected mosquitoes than injected mosquitoes. The median titer of orally infected mosquitoes was 2.0 × 107 PFU/mL with an interquartile range (IQR) of 4.61 × 107, while the median titer for intrathoracic infection was 1.15 × 106 PFU/mL with an IQR of 1.89 × 106. The overall titer range for oral infection was around 103–109 PFU/mL , while that for intrathoracic infection was around 105–106 PFU/mL (100-fold)  A,B. Simi00-fold) . Togethe9 PFU/mL and then titered at 5 days post-blood meal (PBM). The results from this experiment show that mosquito age had a significant effect on median titer after oral infection  was used to orally infect mosquitoes from either the Orlando line or another laboratory Ae. aegypti line, Rex-D  have both been reported to affect the susceptibility of mosquitoes to arbovirus infection ,13,15. Tntration A,B. Infetrations C. Howevetrations A,B.9 PFU/mL and incubated for 5, 10, or 15 days. Results from this experiment showed that the incubation period significantly affected the median viral titer, with the median titer dropping over time   A.p-value = 0.922)  ingested. In all experiments, we routinely selected only mosquitoes that appear to have taken a full blood meal, as assessed by the amount of blood visible in the abdomen. However, to determine whether the amount of blood ingested contributes to variation in titer, the amount of blood ingested by the mosquitoes in = 0.922) B. Togeth4), medium titer (2.9 × 106), or high titer (2.0 × 108) infections in order to determine if these virus populations differed in replication kinetics. We first used these virus populations to infect C6/36 and Aag2 cells, with a P2 stock of MRE-16 prepared by our normal procedure serving as a control. To eliminate the possibility that potential inhibitors present in mosquito homogenate could affect virus replication, medium and high titer virus stocks were serially diluted with mosquito hemogenate  to achieve the desired MOI. The results from the growth curves show that viruses collected from low titer mosquitoes replicated to a lower titer when compared to viruses from high titer or medium titer mosquitoes or stock MRE-16 virus  between vertebrate hosts and invertebrate vectors can affect arbovirus fitness . We thusntration D–F, whilAe. aegypti. In doing so, we learned several important things about the causes of individual variation. First, the route of infection contributes to variation in the virus titer. We observed much greater variation in virus titers after oral infection than after intrathoracic infection, which is consistent with previous reports [Ae. aegypti will be susceptible or refractory to viral infection. The gut microbiome also modulates midgut immune response by modulating the expression of antimicrobial peptides, which can influence the degree to which arboviruses successfully infect and escape the midgut [To begin to explore what biological factors contribute to variation in the arbovirus titer between individual mosquitoes after oral infection, we used SINV as a model organism to study titer variation in a laboratory strain of  reports ,17,29. T reports . In addi reports . The dif reports , Toll pa reports , can infe midgut . Any of Ae. aegypti did not correlate with either the size of the mosquito or the amount of blood ingested. Reports from [Ae. aegypti mosquitoes were significantly more susceptible to Ross River virus than small mosquitoes when fed with viremias of varying titers, the difference in susceptibility was less apparent at higher viremias. Since high virus concentration was used in this study, it may partially explain why there was no correlation between size of mosquito and viral titer. This result suggests that some other intrinsic factor is responsible for individual variation in virus titer, such as the strength of the midgut immune response [We also tested several other factors for their involvement in causing individual variation. Importantly, we showed that the virus titer in rts from  show tharesponse .Ae. aegypti, and when MRE-16 was used to infect two different Ae. aegypti lines, Orlando and Rex-D. A sharp contrast between the median titer and prevalence of infection was observed for MRE-16 versus TE, which was expected since TE is better adapted to replicate in culture [We further considered whether the degree of individual titer variation that is observed is affected by other factors. Our results indicate that the amount of individual variation is not affected by mosquito age or by the concentration of the virus in the blood meal. Furthermore, high levels of individual titer variation were observed when either one of two different strains of SINV, MRE-16 and TE, was used to infect  culture  than to  culture ,23, but  culture .To begin to determine whether there were any differences between the virus populations that accumulated during infection of high, medium, and low titer mosquitoes, we examined the replication dynamics of these virus populations in mosquito cell lines. Results from this experiment showed that the virus obtained from low titer mosquitoes replicated slower and to a lower titer than the virus from high titer or low titer mosquitoes or standard P2 virus, suggesting that there may be genetic differences between these virus populations.To further examine this possibility, refeeding experiments were performed using virus populations obtained from high titer mosquitoes that were either amplified in BHK-21 cells or not. Attempts to perform a refeeding experiment using low titer virus proved futile because we were not able to reinfect mosquitoes or rescue the virus from low titer mosquitoes in culture, presumably due to its low titer. However, results from feeding non-passaged high titer virus to mosquitoes resulted in similar titer variability compared to the P2 stock virus but had a lower median titer and lower prevalence of infection. In contrast, results from the refeeding experiment using the high titer virus that was passaged once in BHK-21 cells showed similar variability compared to the P2 virus but resulted in a higher median titer and higher prevalence of infection than the stock P2 virus. The lower median titer and lower prevalence of infection of the P2 virus compared to other experiments in this study was likely due to the low virus concentration used in this experiment. It was interesting, however, that the virus derived from high titer mosquitoes that had been passaged once was better able to infect mosquitoes and resulted in a higher median titer than the stock P2 MRE-16. This may be attributable to genetic changes in the genome of the virus derived from high titer mosquitoes, which calls for future investigation to ascertain if this is the case. The results from these experiments also show that the virus that came from high titer mosquitoes still caused highly variable virus titers when fed to additional mosquitoes, suggesting that there still is genetic variation in this virus population, and genetic bottlenecks could still result in founder effects . The abiAe. aegypti is orally infected with SINV. Of the several biological factors tested, only the incubation period affected this variation in the SINV titer. The reduced titer variation that was observed due to a longer incubation period may be due to the adaptation of SINV in Ae. aegypti, the action of the mosquito immune system in limiting virus replication, or a combination of both processes. Variation in individual virus titer was significantly affected by the route of infection, leading us to conclude that the midgut appears to be an important tissue contributing to the variation in titer. Our findings also suggest that founder effects, due to the action of bottlenecks on the collection of virus variants present in a SINV population, may contribute to the variability in titer between individually infected mosquitoes. Deep sequencing of the virus derived from high and low titer mosquitoes may help resolve this question. However, consistent genetic changes may be difficult to detect between virus populations obtained from high and low titer mosquitoes since mutations continue to occur in the viral genome as the virus replicates after escaping from the midgut. It also remains possible that variation in the strength of the immune response between individual mosquitoes could play a role in the highly variable titer that is observed after oral infection. We are currently carrying out additional experiments to distinguish these possibilities.In summary, results from this study show that a high degree of individual titer variation is observed when even a highly inbred laboratory strain of


Of the various proteins encoded by plant viruses, one of the most interesting is the movement protein (MP). MPs are unique to plant viruses and show surprising structural and functional variability while maintaining their core function, which is to facilitate the intercellular transport of viruses or viral nucleoprotein complexes. MPs interact with components of the intercellular channels, the plasmodesmata (PD), modifying their size exclusion limits and thus allowing larger particles, including virions, to pass through. The interaction of MPs with the components of PD, the formation of transport complexes and the recruitment of host cellular components have all revealed different facets of their functions. Multitasking is an inherent property of most viral proteins, and MPs are no exception. Some MPs carry out multitasking, which includes gene silencing suppression, viral replication and modulation of host protein turnover machinery. This review brings together the current knowledge on MPs, focusing on their structural variability, various functions and interactions with host proteins. The process of infection of plants with viruses is broadly divided into two types; local and systemic. Local infection is often subliminal and is characterized by intracellular confinement of virus within and nearby the site of infection, while the systemic infection is progressive throughout the host and involves first, the short-distance movement of the virus from the infected cell to surrounding cells followed by long-distance movement using the host vasculature preferably the phloem tissue . HoweverThe intercellular transport through PD depends upon its size exclusion limit (SEL), defined by the size of the largest molecule, which can pass through. Although solely dependent upon the hydrodynamic stokes radius , the PD Despite sharing a common function, there exists a large variation among MPs and their mechanisms of action. In recent years, a number of functions-associated with MPs, namely the mechanisms of modifying the PD SEL, formation of a viral transport complex, interaction with host components and suppression of RNA silencing, have been revealed. In addition, there are other viral proteins that mimic the functionality of MPs. In this review, we have chosen to bring together recent findings on MPs, interactions that they share and the division of labor that they show with other ancillary proteins required for the intercellular movement of plant viruses. Several other previous in-depth reviews present an exhaustive discussion on various aspects governing the intra-, and intercellular movement of viruses and the reader is guided to these for a more holistic understanding of this topic ,12,13,142+ sequestering chaperone protein, restricts the exit of misfolded proteins from the ER and accumulates in the PD .,97.96,97M protein is the MP as displayed by its properties of oligomerization and formation of tubular structures in infected protoplasts and insect cells. It forms and extends the tubule across PDs, assisting the intercellular movement of the non-enveloped nucleocapsids [Frankliniella occidentalis, TSWV NSM protein is functionally linked with autophagic pathways, not involved in assisting the intercellular movements [In the tomato spotted wilt virus (TSWV), a Tospovirus, the NSocapsids . In the ovements .N. benthamiana [The ORF-4 of the groundnut rosette virus (GRV), an Umbravirus, encodes for 28 kDa protein that is PD-localized, binds to both ssDNA and ssRNA cooperatively in a sequence nonspecific manner and induces tubule formation on the protoplasts surfaces in thamiana ,112. Umbthamiana .Comovirinae, Comoviruses, Fabaviruses, and Nepoviruses have molecular weights of 48/58 kDa, 37 kDa and 38–43 kDa, respectively  requires both MP and CP. The MP induces tubule formation and exhibits RNA-binding capacity in a sequence nonspecific manner. An intact virion formation is not necessary for the intercellular movement of the virus; however, the association of MP with CP is crucial, as observed by restricted intercellular movement following mutation of CP .Chenopodium sp. The MP interacts with N. benthamiana protein (NbNACa1), which apparently regulates its localization on PD [While most of the brome mosaic virus (BMV) strains do not require CP for intercellular movement , the tubon on PD .N. benthamiana) than its natural host (cowpea), as demonstrated when CP was replaced by an enhanced GFP [In another Bromovirus, the cowpea chlorotic mottle virus (CCMV), MP is sufficient (no CP required) for intercellular movement. Interestingly, the rate of intercellular movement is host-dependent, being faster in an experimental host  tubule forming MP is PD-localized and binds to ssRNA . CMV MP ormation .Bromoviridae where the similar domain lies at the C-terminal. This may have evolutionary implications showing phylogenetic divergence among viruses belonging to the family Bromoviridae [The MP of prunus necrotic ringspot virus (PNRSV), an Ilarvirus, also binds to ss RNA in a sequence-nonspecific manner. A 33 aa domain at the N-terminal of MP is crucial for ss RNA binding as found out by deletion mutagenesis followed by Northwestern analysis. The N-terminal location of the RNA-binding domain in MPs encoded by Ilarviruses and Alfamoviruses are different from MPs encoded by other members of the family oviridae .Bromoviridae also show high functional variability in the dependence of their MPs on CP as well as tubule formation. With the current findings, a correlation between CP interaction and tubule formation by the MP can be established. MPs requiring CP for virus movement may form tubule, and the ones, which do not require CP may move by gating the PD. However, it requires further conclusive studies involving both the variability in virus species and strains as well as the host range to establish this functional relationship.Members of the family RNA interference (RNAi) is a fundamental mechanism of regulation of gene expression in eukaryotes both at the transcriptional and post-transcriptional level by specific mRNA degradation through complementary small RNA . RNAi isIn this regard, it is important to note that either the MP in itself or another movement-associated protein may act as VSR  ,158 or tIt is abundantly clear that MPs have evolved diverse mechanisms to accomplish their goal of ensuring the transport of viruses across the host imposed natural barriers  and provoke a successful, productive systemic infection. Although highly variable, MPs interact with a plethora of viral as well as host factors, facilitating the movement of the viral genomes to and through PD. Studies on viral MPs indicate that the virus movement is spatially and temporally coupled with replication, encapsidation and suppression of host RNAi-mediated defense, and all this involves a close association of viral MPs with the host PD, cell cytoskeleton, endomembrane system and the secretory pathway.Further progress in our understanding of their actions will probably be achieved by revealing finer details of their structures and interactions with components of PD and other viral proteins. Whether MPs also play a role in the tissue tropism of certain viruses may be revealed by better understanding the functions of various PD types in tissues and their interactions with MP. A new aspect of the function of MPs is emerging when one considers their role in non-cell-autonomous functions in plants, a subject which may have implications in viral pathogenicity. Several outstanding questions that can be put forward are:What is the role of the tertiary structure of MPs on their interactions with key proteins of PD? How does the specific function of MP change upon post-translational modifications? Are there variants of PD-localization signal in MPs structurally different from each other? If yes, then how do the various membrane contact sites/receptors differentiate between these signals? Is it possible that the limited non-cell-autonomous functions known in plants are intimately modified by MPs? Is cellular conditioning at the infection front before the virus spread a general phenomenon acquired by viruses of the “30 K” superfamily clan, or the mechanism extends to other viruses with non-related MPs too? How does the role of MPs known in RNA silencing suppression impact their effect on the intercellular spread of viruses? In tubule-forming viruses, what is the mechanism by which MP modifies the PD components in forming the tubules?Finally, one can look forward to further developments in super-resolution- and fluorescent probe-based 3-D microscopic techniques for a clearer picture of the interactome of MPs. In addition, the detailed study on MP interaction and function can yield a significant amount of information about the response of the host cellular machinery, not only towards viral infection but also may provide a novel handle for the better understanding of cellular machinery for intercellular movement of macromolecules and other substances (both cellular and foreign) across PD.


The dominant role of the CNC’s colloidal suspension properties, such as the viscous force, inertial, and surface tension forces in the fluid dynamics was quantitatively evaluated in the formation of drops and jellified beads. The similarity and difference between the behavior of carbohydrate polymers and rod-like crystallites such as CNC were enlightened. Pump-driven and centrifugally-driven external gelation approaches were followed to obtain CNC hydrogel beads with tunable size and regular shape. A superior morphological control—that is, a more regular shape and smaller dimension of the beads—were obtained by centrifugal force-driven gelation. These results suggest that even by using a simple set-up and a low-speed centrifuge device, the extrusion of a colloidal solution through a small nozzle under a centrifugal field is an efficient approach for the production of CNC hydrogel beads with good reproducibility, control over the bead morphology and size monodispersion.The influence of the physical, rheological, and process parameters on the cellulose nanocrystal (CNC) drops before and after external gelation in a CaCl Theseon agent . The facon agent ,9. Accoron agent . Althougon agent , and beaon agent . The moron agent . Convers−1) showed that all the investigated samples behaved as liquids, since the viscous modulus G″ was higher than the elastic modulus G′  was applied. For a series of experiments, ΔP were kept in the range 8–13 kPa, depending on the CNC concentration, in order to obtain a flow rate P values, we did not observe the formation of drop satellites. On the other hand, a clear dripping to jetting transition was observed if −1 CNC solution.2 was used as gelation bath. This CaCl2 concentration value was found as the optimal one, since it allows fast and stable gelation of CNC. Higher salt concentrations were not considered in order to avoid substantial perturbation of the chemical and physical properties of the aqueous bath. Moreover, the gelation process is diffusion controlled [2+ concentrations are expected not to leave a relaxation time long enough for the droplets to regain their spherical shape after colliding with the gelling bath. In some experiments, 60 μM Tween 20 was added to lower the surface tension. Representative pictures of the obtained beads are shown in An aqueous solution containing 0.1 M CaClntrolled , and higmaxd) of the beads obtained by the syringe apparatus of 2 solution and to the impact of the droplet with the gelling bath surface. In fact, the beads obtained with higher CNC concentrations  and maximum (maxd) dimension (details in the Methods) to calculate the two different dimensionless shape indicators—that is, the sphericity factor (SF) and the aspect ratio (AR)—at different collecting distances. These values are reported in SF values always > 0.05 indicate that the beads are spherical ellipsoids at all the collecting distances, but in spite of the large variability of the averaged SF value, some spherical beads were observed at 20 cm collecting distance.The largest dimension . In thite’s law ,16, Equa2 mNm−1, ,18) is tA 2+ crosslinked CNC beads was calculated from the ratio A shrinkage factor lginates , CNC droOh) was used to obtain a quantitative evaluation of the importance of the viscous force to surface tension force in determining the bead formation. In particular, under our experimental conditions, the Oh number could account for the effect of the CNC solution properties on bead shape transition observed at different collecting distances [The non-dimensional Ohnesorge number  by using a home made centrifugal-force-driven micronozzle system, the sketch of which is shown in We investigated the production of the hydrogel beads under the artificial gravity :To obtain a rational picture of the size dependence on the experimental parameters, we consider that the droplet detaches from the nozzle when the gravitational pseudo-force surpasses the surface tension force , Equatio−1 CNC at −1, which is comparable to that reached in the centrifuge bucket. It can also be expected that the jet expansion is more pronounced at the very low Reynolds number estimated in our conditions, since relatively low velocity and high viscosity contribute to viscoelastic response of the fluid to capillary stress and relaxation [Analogously to the equations obtained for the production of beads by extrusion dripping, the bead shrinkage and the liquid lost factors should be taken into account. However, in light of the small contribution of these factors in the dripping experiments, in the following analysis, we neglect them. If the simplified calculation in Equation (8) holds, we estimate a theoretical e impact . Our date impact . Middlement b=−0. ± 0.08 i−1. The details of the nanomaterial characterization are reported in All the reagents were from Sigma Aldrich-Merck . Cellulose pulp was a kind gift of Sca . First, 10 g of pulp were swollen in water for 1 h and bath sonicated for 30 min. Then, 160 mg TEMPO, 1 g NaBr, and 35 mL 12% NaClO were added according to the method of Saito and Isogai , which w−1 at 20 °C. Then, the density of a 14.7 gL−1 CNC solution was calculated using this volume and the experimental value of the mass of the CNC solution, finding 1.0050 ± 0.0003 kgL−1 (N = 7).The density (ρ) of a CNC solution CNC was measured at 20 °C using a pycnometer, the volume of which was calculated by measuring the mass of the deionized water necessary to fill it and taking a water density value of 0.9982 KgL2 bath, we used a set-up consisting in a syringe equipped with a metallic needle with an outer diameter (dt) and an inner diameter (di) of 636 ± 4 μm and 225 μm, respectively, connected to Elveflow Microfluidics Flow/Pressure Control System . A CaCl2 reservoir was located at a variable distance from the needle tip.To produce CNC beads by extrusion dripping and external gelation in a CaCl2 solution. The Falcon tube was placed into holes of a swinging bucket rotor of a centrifuge . Centrifugal accelerations in the range CNC beads were produced by a centrifugally driven pulse-free flow approach consisting of a pipette tip working as a CNC solution reservoir. This pipette tip was sealed by an adhesive to a glass or polyethylene capillary of variable length from which droplets of the CNC solution were released. This device was held firmly in a fixed position by inserting it in the central hole of a Teflon support. Then, the Teflon support was fit inside a 50 mL Falcon tube, the bottom of which contained the gelling bath; i.e., a 0.1 M CaClThe size and shape of the beads were investigated using the experimental photos and the image processing platform ImageJ  .The beads produced by pump-driven external gelation were withdrawn from the gelling bath, and the excess of solution was gently removed with a blotting paper. Then, the beads were laid down on a support covered with graph paper, and photographs were taken.2 solution, and the photos were taken by a stereo microscope .The beads produced by a centrifugal-force-driven micronozzle system were poured into a Petri dish containing a 0.1 M CaClSF) and the aspect ratio (AR), see Equations (9) and (10):The maximum diameter The shrinkage factor, Equation (11):The volume of the solution drops was calculated from the experimental weight of the drops using the density value of the CNC solution. The volume of the gelled beads was experimentally measured. Details of the procedures used to this purpose are reported in the The liquid lost factor, Equation (12):te’s law  and obta2+ coordination. Moreover, we observed that CNC solutions undergo tensile stress inside a capillary and CNC drops do not shrink upon gelation; conversely, they slightly expand.In conclusion, in this paper, we highlighted the physical parameters and the processing conditions to control the hydrogel bead production by using a pump-driven and a centrifugal-force-driven external gelation. The latter is a superior approach to fabricate size and shape-controlled beads by using simple and cheap laboratory equipment. In fact, with the aid of centrifugal fields, smaller and round shaped beads can be obtained. Beyond the possible application of this result, our systematic investigation provides an overview on properties of CNC solutions as a fluid and estimates the role of forces  in the CNC solution jets. By this study, we observed important differences between the behavior of CNC solutions and the carbohydrate polymers such as alginates. In general, the CNC bead dimensions are larger than those of carbohydrate polymers, and their shape is more irregular. This is probably due to the crystallinity of CNC, which could affect both the folding at the nanoscale and the availability of carboxylate groups for Ca


Many researchers have pointed out that decreased sagittal range of motion (ROM) in the affected hip joint is a common consequence of stroke, and it adversely affects walking performance and walking speed. Nevertheless, the minimal clinically important differences (MCID) in hip-related kinematic gait parameters post-stroke have not yet been determined. The present study aimed to define MCID values for hip ROM in the sagittal plane i.e., flexion–extension (FE), for the affected and unaffected sides at a chronic stage post-stroke. Fifty participants with hemiparesis due to stroke were enrolled for the study. Four statistical methods were used to calculate MCID. According to the anchor-based approach, the mean change in hip FE ROM achieved by the MCID group on the affected/unaffected side amounted to 5.81°/2.86° (the first MCID estimate). The distribution-based analyses established that the standard error of measurement in the no-change group amounted to 1.56°/1.04° (the second MCID estimate). Measurements based on the third method established that a change of 4.09°/0.61° in the hip ROM corresponded to a 1.85-point change in the Barthel Index. The optimum cutoff value, based on ROC curve analysis, corresponded to 2.9/2.6° of change in the hip sagittal ROM for the affected/unaffected side (the fourth MCID estimate). To our knowledge, this is the first study to use a comprehensive set of statistical methods to determine the MCID for hip sagittal ROM for the affected and unaffected sides at a chronic stage post-stroke. According to our findings, the MCID of the hip FE ROM for the affected side amounts to 5.81° and for the unaffected side to 2.86°, in patients with chronic stroke. This indicator is extremely important because it allows clinical practitioners to assess the effects of interventions administered to patients, and to interpret the significance of improvements in sagittal kinematic parameters of the hip; ultimately, it may facilitate the process of designing effective gait reeducation programs. Stroke is the second most common cause of mortality worldwide and the third most frequent cause of disability and premature death . Stroke The importance of gait kinematics assessment was emphasized by Boudarham et al. . As estaIt has been established that 3DGA kinematic indices are most reliable in assessing the hip and knee in the sagittal plane , 14. ConFrom clinical practitioners' viewpoint, the MCID is highly useful since it enables the evaluation of effects achieved by patients receiving therapy; it may also provide effective support in the process of designing treatment strategies , 28. GivFifty individuals after a stroke in a chronic phase of recovery  were identified in a database of a rehabilitation clinic. The following eligibility criteria were specified for those recruited for the study: age in the range of 30–75 years; single ischemic stroke experienced; a minimum of 6 months from the stroke incident; unilateral paresis; Brunnström's motor recovery stages 3–4; and a score of 3 or more in the Functional Ambulation Category walking test, including an ability to get up and walk a minimum distance of 10 m without support from another person . Exclusion criteria were defined as follows: recurrent stroke event(s) experienced, unstable medical condition, orthopedic impairments in the lower extremities, inflammation and/or pain in the musculoskeletal system adversely affecting gait and/or associated with a need to take anti-inflammatory drugs, and inability to grasp the instructions and to perform required tasks due to cognitive disorders. The study protocol was approved by the local Bioethics Commission at University of Rzeszow's Medical Faculty. Compliance with the Declaration of Helsinki was ensured. Informed consent was given in writing by all the study participants. No adverse events occurred during the study procedures. The demographic and clinical characteristics of the study participants are presented in Kinematic hip data were acquired using a motion capture system  equipped with six cameras, two force plates, and software, including SMART Capture, Tracker, and Analyzer functions. In line with the Davis Marker Placement system, passive markers were positioned on the participants' skin, in the following locations: the sacrum, pelvis (the posterior and anterior iliac spine), femur , fibula , and foot  . The sysThe Barthel Index (BI) enables assessment of patients' functional independence in activities of daily living. It covers 10 aspects, such as feeding, toilet use, and mobility. BI is commonly used in clinical practice in assessing performance of patients after a stroke , 31. It For the needs of the anchor-based analyses, the patients' hip ROM was measured using 3D gait assessment, at baseline (the day of the patients' admission to the rehabilitation clinic) and at follow-up (4 weeks after the first assessment). On the latter occasion, the patients were asked to report any self-perceived change in their hip ROM, observed by comparison to their condition before the therapy. Based on their self-reported perceptions, the patients were divided into three groups: the “no-change group” comprised those who reported their hip ROM was unchanged, “the MCID group” (or “positive change group”) comprised those who reported improvement, and the “negative change group” consisted of those who reported deterioration of their condition.The distribution-based analyses took into account the no-change group only; i.e., the standard error of measurement (SEM) was computed for the patients reporting no change in their hip sagittal ROM in the period between baseline and the follow-up assessments.A linear regression analysis was applied to examine a change in the hip sagittal ROM by comparison to the MCID in the BI.The ROC curve approach was applied to determine the cutoff point for the change in the hip sagittal ROM, most effectively separating the “positive change group” and the “no-change group” with the ROC curve.The therapy provided to the patients between the baseline and the follow-up continued for 150 min per day; its program comprised individual practice, including active and assisted exercise of the upper and lower limbs, balance exercise in sitting and standing position, gait reeducation, breathing exercises, and training in activities of daily living.p < 0.05. The comparative analyses took into account mean differences and a 95% confidence interval (CI). Four approaches were applied to calculate the indicators of change achieved in the hip FE ROM, separately for the affected and unaffected sides, and the highest value was assumed to reflect the relevant MCID. The anchor-based approach was applied to determine the first estimate for the MCID, i.e., the mean positive change in the hip FE ROM separately for the affected and unaffected sides in the MCID group (Statistica 13.1 (StatSoft) was used to carry out all the statistical analyses. In line with the adopted assumption, significant effects were reflected by ID group –35. The ID group , 36. LinID group , 38. TheID group , 40.The calculation of the minimum sample size was based on the number of patients with stroke admitted annually to the rehabilitation clinic; the records showed that ~200 patients received stroke-related treatment at the facility, and 40% of those were at a chronic stage of recovery post-stroke. It was assumed that 80% of the latter patients would present a minimum gait speed exceeding 0.4 m/s and that an improvement of more than 0.06 m/s would be achieved by 80% of the patients in our group . A fracAs regards the anchor-based analyses, the findings showed that, at the follow-up, deterioration in the hip FE ROM was not reported by any patients as a result of which only two groups (MCID/positive change and no change) could be distinguished based on the patients' perceptions of the hip sagittal ROM. The MCID/positive change group comprised 42 patients while 8 patients were allocated to the no-change group. The anchor-based estimate was calculated taking into account the changes identified in the MCID group only. On the affected side, the mean change in hip FE ROM amounted to 5.81° and that figure was defined as the first estimate of the MCID of the hip FE ROM for the affected side. On the unaffected side, the mean change in hip FE ROM amounted to 2.86°, and that figure was defined as the first estimate of the MCID of hip FE ROM for the unaffected side .Distribution-based analyses were applied to the no-change group only. The SEM amounting to 1.56° was defined as the second estimate of the MCID of the hip FE ROM for the affected side. The SEM of 1.04° was defined as the second estimate of the MCID of the hip FE ROM for the unaffected side .The slope of the regression line was 2.209 which means that a one-point change in the BI corresponded to a 2.209° change in the hip FE ROM for the affected side ROM . This meThe ROC curve analyses showed that the optimum cutoff points corresponded to the values representing 2.9° and 2.6° change in the hip FE ROM for the affected and unaffected sides, respectively —the fourThe findings related to patients with chronic stroke showed that the highest of the four MCID estimates of the hip FE ROM for the affected and unaffected sides amounted to 5.81° and 2.86°, respectively, and these values are defined as the MCID for these parameters.The aim of this study was to determine MCID values for hip FE ROM for the affected and unaffected sides in patients at a chronic stage of recovery post-stroke, using four approaches: a patient anchor-based method, a distribution-based method, linear regression analysis, and specification of the ROC curve. The major findings were that the highest of the four MCID estimates of the hip FE ROM for the affected side amounted to 5.81° and for the unaffected side to 2.86°, which is the first estimate of MCID for hip FE ROM in patients with chronic stroke reported in the related literature.Based on the literature review, it can be concluded that the effectiveness of gait reeducation can successfully be assessed using the objective evidence provided by kinematic analysis of gait , 7–9, 42p < 0.05) in the flexion–extension ROM of the hip joint during the affected side trail (11.63), affected side lead (21.25), and unaffected side trail (0.61) section underwater (p = 0.014) and better results after the intervention  located in a hospital building. The measurements on both the unaffected and affected sides were divided into the lead and trail sections. The authors showed significant changes p < 0.0 in the frvention . If thesThis study is thought to be quite meaningful because it provides the first ever estimates of MCID for hip FE ROM, separately for the affected and unaffected sides in the chronic period post-stroke. The estimates were performed using four statistical methods, which significantly increases the likelihood that the computed values are reliable and valid. However, this study has some limitations. Firstly, estimation of the MCID for ROM of the hip joint was limited to flexion and extension. If more diverse ROM of stroke patients' hip joints  were taken into account, more scientific grounds could be presented in interpreting the significance of the changes observed in the kinematic parameters of the hip; this would constitute a greater contribution toward further advancements in gait rehabilitation programs for patients at a chronic stage post-stroke. The fact that the present study focused on estimation of MCID for hip sagittal ROM only is linked with the evidence reported in the related literature, and more specifically in a robust systematic review based on 23 studies investigating the reliability of 3DGA kinematic gait measurement, and suggesting that DGA kinematic indices related to the hip and knee in the sagittal plane present the highest reliability, while the lowest reliability and highest error are frequently found in measurements of the hip and knee in the transverse plane . MCID foTo our knowledge, this is the first study to use a comprehensive set of statistical methods to determine the MCID for hip sagittal ROM for the affected and unaffected sides at a chronic stage of recovery post-stroke. The current study presents evidence showing that the MCID of the hip FE ROM for the affected side amounts to 5.81° and for the unaffected side to 2.86°, in patients with chronic stroke. This information is very important for clinical practice because it facilitates evaluation of progress achieved by patients as a result of interventions, enables interpretation of the changes observed in sagittal kinematic parameters of the hip, and may be used in designing gait reeducation programs.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by Bioethics Commission at University of Rzeszow's Medical Faculty. The patients/participants provided their written informed consent to participate in this study.AG: conceptualization, methodology, formal analysis, and writing—original draft preparation. MD, LP, AW-N, AT, and PK: investigation, data curation, writing—review and editing, and visualization. All the authors contributed to the article andapproved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Conclusion: Although floorball is still a relatively minor sport, its impact on sport-related injuries must not be underestimated. Injuries to the eyes are particularly common. In our opinion, our findings provide strong evidence that all floorball players (not only children and adolescents) should wear protective eyewear. We conclude that the Swiss Floorball Association (Swiss Unihockey) should mandate the use of protective eyewear.Background: The popularity of floorball has surged throughout Switzerland in the last 20 years. However, epidemiological studies are still scarce. Objective: To collect information on floorball-related injuries, their severity and approximate cost in adults who presented to our emergency department from 2013–2019. Moreover, to use this information to suggest possible strategies to prevent injuries. Materials and Methods: The study population includes all patients who suffered injuries related to floorball and were then seen at the University Hospital in Bern during a 7-year period. Bern University Hospital, Switzerland, has a comprehensive management system (Ecare) that was used to generate the data for this study. The data were then used to create an injury profile of all cases presented during the said period. Results: A total of 263 injures were recorded from 2013 to 2019. The most common locations for injuries were to the eyes (43.73%), followed by the lower extremities (25.48%). The mean cost per case was CHF 1191.43. However, the vast majority of admissions could be sent home (93.16%) and did not cost more than 500 CHF/case (57.41%). Of the 22 cases that cost more than CHF 2000, 10 were located around the torso and 6 affected one or both eyes. Significant differences were observed between the age groups and treatment area ( The sport of floorball is becoming increasingly popular around the world. At the end of 2019, the International Floorball Federation counted around 375,000 registered players in over 70 countries, with 33,500 in Switzerland alone. This excludes the many amateur floorball players, as well as individuals who play floorball in the context of physical education [Floorball is a sport that is said to be similar to ice hockey, but without the ice or the skates. Players in teams of six manipulate a light, hollow, plastic ball with graphite sticks. Points are acquired by scoring goals. One match consists of three 20 min sessions with ten-minute breaks in between ,4,5. TheHowever, in spite of the sport’s susceptibility to injury and its growing popularity, there are not many scientific studies on floorball injuries. A few studies have been conducted in Sweden and Finland on the incidence of injuries in floorball ,8,9. TheImplementation of protective measures is the responsibility of the federation and its players. Epidemiological studies can, however, be an important tool in identifying the risks of the sport and most common sites of injury and may trigger valuable suggestions for new preventive measurements. For example, Leivo T et al. ,16 perfoAccording to the statistics of the Swiss Council for Accident Prevention (BFU), 11,430 accidents were associated with floorball between 2013 and 2017 . AlthougIncreasing healthcare costs are a worldwide problem. The number of visits to emergency rooms is also increasing worldwide, and in addition, ED (Emergency Medicine) care is more expensive than other forms of health service ,20. LampIn addition to the impact on players’ health, injuries also have socioeconomic impacts. For this reason, floorball injuries are an important area of interest for emergency departments. If there is a fundamental understanding of the casualties, injury types, injury localization and their injury mechanisms, this can provide the basis for adequate patient services and evidence-based strategies for prevention. The epidemiology of related injuries can lead to regulatory changes, equipment changes, training in specific skills and coaching.This study aims to describe patients with floorball injuries presenting to an adult emergency department between 2013 and 2019 in order to better understand injury patterns and identify risk factors for floorball injury.The goal of the present study is to investigate floorball accidents in order to record epidemiological data and to analyze the mechanism of injury, its causes and resulting damage. An additional goal is to define simple preventive measurements on the basis of the information obtained.This was a descriptive retrospective study including adult patients (≥16 years) admitted to our emergency department in Bern due to accidents while playing floorball and within the period from 2013 to September 2019. The Department of Emergency Medicine (ED) at Inselspital , Bern, is the only center for major trauma treatment in Bern, with a catchment area of 1.5 million people. In 2019, more than 50,000 patients were treated in the Department 24/7.. The data for this work were generated from the database of the management system of Bern University Hospital, Switzerland .A total of 331 cases were collected in that period, including 263 eligible patients who were further analyzed in our study . The datInclusion criteria were as follows: patient suffered an accident while playing floorball, patient’s age ≥16 years and presenting in our emergency department within the defined period. Swiss medical policy defines adults as patients of 16 years or more; all patients younger than 16 years are treated at the pediatric emergency department.The following clinical data were extracted from the medical database: diagnosis (type of injury), circumstances of the accident (mechanism of injury), site of injury and accruing costs pertaining to the case . The diagnosis was categorized as the major injury with the greatest impact on the patient, and each patient was only allocated to one diagnosis group. If it was not possible to locate one single principle injury, the case was categorised as combined injuries (without life-threatening injuries) or polytrauma. Demographic data such as age and gender were also included, as well as chronological data, such as year of arrival in the emergency department, treatment area, route of admission and route of discharge.At the ED, patients are routinely triaged using an abbreviated version of the Manchester Triage System  . This tr® 13.1 . The distribution of categorical variables is given with the absolute number and the relative number as a percentage. A comparison of the clinical parameters was made between the sex , year of consultation , and age groups . A patient with missing data on the treatment performed was excluded from the statistical analysis here.The data were summarized using descriptive statistics . The statistical analysis was performed using Stata2) test and the Fisher exact test. The threshold of significance was set at p = 0.05 (two-tailed).Categorical variables were analyzed using the chi-square  ethics committee in Berne (No. 2020-1776) and followed the guidelines of the Declaration of Helsinki and ethical principles for conducting medical research with human subjects . No indi“Floorball” (German “Unihockey”) was identified in both databases for 331 patients. One hundred fifty-three patients (153) were excluded, as their admission was not related to floorball, or the patients were younger than 16.. p = 0.722). In the comparison between the analyzed years, no statistical differences were observed for the following parameters: age group (p = 0.722); triage group (p = 0.927); treatment area (p = 0.737); route of admission (p = 0.559); route of discharge (p = 0.121); type of injury (p = 0.704); body part (p = 0.257); location of injury (p = 0.527); mechanism of injury (p = 0.677); costs (p = 0.538). The type of trauma was the only parameter that changed significantly over the analyzed years (p = 0.006).Twenty-one patients were excluded due to disagreement with the General Consent. For the period from January 2013 to December 2019, two hundred sixty-three (263) cases with floorball accidents were eligible for further analyses . Table 1p = 0.008), costs (p = 0.008), route of discharge (p = 0.023) and type of trauma (p = 0.020). In the comparison between the age groups, no statistical differences were observed for the following parameters: sex (p = 0.546); year of consultation (p = 0.927); triage group (p = 0.140); route of admission (p = 0.663); type of injury (p = 0.612); body part (p = 0.113); location of injury (p = 0.058); mechanism of injury (p = 0.570). Two hundred thirty-four patients (88.97%) were male and 29 (11.03%) were female . Significant differences were observed between the age groups and treatment area  admissions, followed by the lower extremities, with 67 (25.48%) cases. The third most common location for injuries was the face and head, with 33 cases (12.55%) . The han).Contusions were the most common mechanism of injury, with 146 (55.13%). In 34 patients (12.93%), the type of injury was a joint distortion, with the ankle region as the most affected body area. Twenty-six (26) patients (9.94%) broke a bone , most ofTable 2). The bubble chart (In 103 patients (39.16%), the reason for an injury was a “blow with a ball”. This was followed by either “tripping over the player’s own feet or their own stick”, with 48 (18.27%) admissions. In a total of 34 (12.90%) cases, the cause for an injury was either “direct player contact”, such as tripping over other player’s feet, or a “direct tackle” from an opposing player. Twenty-five admissions (9.51%) were due to an injury where “no contact” was the mechanism of injury . In thosTable 2le chart  shows thp = 0.008).The therapy plan depended on the reason for admission. The most common type of treatment was “discharge home with or without analgesia” in 107 cases (40.68%). Fifty-seven  patients received a cast or a hard sole. For 4 (1.52%) patients, immediate operation was indicated, for example, surgical treatment of a medial femur fracture. One hundred and forty-six  patients were additionally asked to come in again or to visit their family doctor for a follow-up. The treatment area was significantly associated with the age group  were suffering from a monotrauma. Twenty-two (8.37%) patients suffered non-life-threatening polytraumatic injuries and six (2.28%) patients suffered life-threatening injuries .n = 211, 80.23%). Thirteen  patients were brought by an ambulance, and 38 (14.44%) were referrals from other doctors or hospitals. Only one patient was referred to the emergency department by “callmed”, which is a health-insurance-specific medical telephone helpline to evaluate whether a doctor’s referral is indicated or not  patients were able to go home after their emergency room admission. Sixteen  were admitted as in-patients. Six patients had injuries to an eye, five to their torso and head, four to their lower extremities and one to their upper extremities. All of those patients were admitted, as the severity of the incident required medical observation or immediate surgery. Two (0.76%) were transferred to a different hospital; one needed surgery and had to be transferred to a hospital closer to home and the other was transferred back to the hospital from where the patient had come.Furthermore, one patient of age 62 suffered a cardiac arrest whilst playing floorball. The patient passed away in hospital after returning to spontaneous circulation. According to the hospital files, no prior heart conditions were known .The triages were performed at the point of admission by the medical personnel admitting the patient to the ED. A triage is performed to assess how urgently a patient needs to be seen by a doctor for the first time. Triage level 1 (“acute life-threatening”) is the highest level of urgency and a doctor has to see the patient within 10 min of his or her arrival. Triage level 2 means that the patient has the level of “highly urgent” and the doctor must have had his first contact with the patient within 30 min. For triage level 3 or “urgent”, this initial medical contact must be within 90 min. The lowest level of triage is level 4 (“less urgent”) for the ED, for which the patient may have to wait up to 2 h until (s)he sees a doctor. In our study, the patients were mostly triaged on level 3 (193 patients or 73.42%). Fifty (50 patients 19.01%) were triaged on level 2. Only 16 patients (6.08%) were triaged on level 4. Only 4 patients (1.52%) had such a severe injury such that they were triaged on level 1 .Unfortunately, not enough information was available about the circumstances of the individual incidents, such as whether the incident happened during a game or a training session and if the player was wearing any protection.No significant differences were observed between the route of admission and route of discharge in relation to age groups, sex distribution and year of consultations .The range of cost per case was between CHF 93.47 and CHF 26,188.70. The mean cost per case was CHF 1191.43. The inpatient cases all cost more than CHF 2000. Between 3013 and 2019, the admissions associated with floorball had a cumulative cost of CHF 313,346.03.The year with the highest costs was 2015, with a total of CHF 74,085.22, but the mean cost was CHF 2057.92. It is surprising that 2015 was not the year with the most cases. However, in 2015, three admissions cost over CHF 10,000.00 each. In those three admissions, the patients were treated by the orthopedic team and had to have surgery, for example, due to a fracture. The year with the lowest mean costs was the year with the second most admissions namely 2016 with 51 admissions mean costs of CHF 529.07.A total of 10 cases made up almost 50% of the hospital expenses, with a mean of CHF 15,478.86 and a total of CHF 154,788.55. Eight of these were admitted to the hospital ward, either for monitoring or surgery. One of the ten patients was admitted to the hospital by the helicopter ambulance and one patient was the patient who suffered a fatal cardiac arrest. There was no medical department that was responsible for all 10 of these patients.The most expensive department was the orthopedic department, where the mean cost was CHF 8745.93 and the total final costs were CHF 43,729.64 for only five patients. The Ophthalmology Department treated 115 patients, with the second highest hospital expenses of a total of CHF 41,886.58 and a mean of CHF 387.84. Another highly expensive department was the Department of Orofacial Surgery, with only three patients and total costs of almost CHF 40,000.p = 0.008). Higher costs were generated in the older age groups (56–65 and >65).The age group with the highest total costs was the group of patients between 16 and 25 years of age, with mean hospital expenses of CHF 1176.04 and a total of CHF 139,949.16. The age group with the highest mean cost was the group of patients aged 56–65 years. This was because this group of 10 patients included cases with high hospital expenses of up to CHF 20,000. A statistically significant association was observed between costs and age , but for female patients, knee injuries were the second most common (13.79%).Our study found no statistical differences between men and women in any of the parameters. Although we only saw a small number of knee injuries overall, these findings correspond to several other studies about the vulnerability of female floorball players for knee injuries .The main focus of our study was to portray an adequate picture for acute traumatic floorball injuries. This acute character was mirrored in the number of patients who came 0 to 1 days after the incident, namely 79.08%. On the other hand, not all types of injuries were recorded equally precisely. Mainly chronic injuries, such as overuse, were registered in only small numbers. We recorded five cases of overuse in this time period that led to acute aggravation of the symptoms, whereas studies with different settings or even different definitions of injury have found much more frequent overuse injuries ,26.The main finding of this study was that the great majority of admissions were caused by an injury to the eye—both in female and male players. Of 263 cases seen during our 8-year observation period, 115 (43.73%) had an eye-related injury. Almost all cases suffered eyeball contusion , but at least 76 (28.90) patients were also diagnosed with hyphemia (bleeding of the anterior eye chamber). The most common cause was being directly hit by a ball, and only eight patients were hit by a stick. Hence, 110 cases were monotraumatic and only concerned the eye. Unfortunately, only in 19 cases was it documented whether the player was wearing some sort of eyewear at all, and only five players stated that they had actually worn this eyewear during the accident. Of those five documented cases, one was hit by the ball, but all others were collisions with forces that were too great for the protective eyewear. A specific example of such a case was when the patient was stated in their history to be wearing floorball eye protection glasses, which shattered on impact with the ball.It may seem that the majority of these eye-related injuries were mild. Ninety-eight (98) cases did not generate more than CHF 500.00 costs, and only five patients had to be hospitalized. The rest could be sent home. However, the gravity of eye injuries must not be underestimated. Most recent sports-related ophthalmological reviews seem to indicate that there is an increased risk after injury of developing future eye-related problems. One study found an increase of 3–4% in the incidence of glaucoma in a 6 month follow-up after an ocular contusion. Another even found an increase of up to 10% in the risk of glaucoma in a 10 year follow up .Our second most common eye-related diagnosis was hyphemia, which also seems to be connected with a lifelong increased risk of glaucoma. In a study by Siu-Chun Ng et al. in 2015, 6.5% of the patients with traumatic microhyphemia were diagnosed with glaucoma 6–98 months after the trauma . Lastly,Floorball-related eye injuries are a subject of long, ongoing discussions, with the earliest studies dating back as far as 1999 and 1995 ,29. DataOne follow-up study at the Helsinki University Eye Hospital in Finland compared sports-related ophthalmologic cases before and after the introduction of mandatory protective eyewear in players under 14. It is interesting that they found that, although floorball was still the most frequent sport in Finland to cause eye injuries , the most common age group shifted from the 10–19-year-old patients to the 40–49-year-old patients. Only one floorball-related eye injury under 14 years of age was recorded, which happened during a non-organized practice without eyewear being worn. This shows that, by wearing appropriate eyewear, any sort of floorball-related eye injuries can be prevented .Since then, several other countries have made protective eyewear mandatory for adolescents—most recently Switzerland and Austria. Starting from the 2020/2021 season, every player aged 16 years or younger has to wear protective eyewear . AlthougIn total, the lower limbs were injured less often than eyes. In this group, the ankle and knee were the most frequently injured parts of the body: 22/67 (32.84%) and , respectively.According to other studies, knee injuries and especially ACL ruptures, are a considerable problem, as they are common in floorball . ACL rupThe third most frequently injured body part was the face . Unlike those to the eye, most head accidents were not caused by the ball (only 6.0%) but rather by direct player contact (33.33%) or as a result of a tackle (18.18%).This seems rather unusual, because most epidemiological studies have found that injuries to the lower extremities, especially the knee and ankle, are the most frequent sites ,14,34,35In our analysis, the most common type of injury was contusion (55.54%). The next most commonly observed types were distortion (12.93%) and bone fracture (9.89%). As regards the type of injuries, we saw a surprisingly high number of bone fractures, with almost 10% of all recorded injuries being fractures. This is especially striking, since contrary to our expectations, the most frequent fractures were not on the extremities. Fifty percent of all fractures were located in the head or torso, whereas upper and low limbs were each only involved in 25% of the cases. The most common fracture location was the nasal bone (four cases), followed by the ribs and the clavicle (three cases each) . VariousIn the current study, 39.16% of the mechanisms of injury were a blow with a ball, followed by “direct player contact”, with 12.92%. Sixty-eight percent (68%) of all injuries are reported to occur without direct contact to the injured body region .In contrast to ice hockey, checking and other harsh body contact are forbidden in floorball. Nevertheless, due to the speed of the game and the tight spaces it is played in, unnatural movements with the potential for injuries happen several times during a game. Normally, these risks are reflected in the number of players injured due to direct or indirect contact with other players. Because of the relatively high numbers of eye injuries compared to the extremities, this was not the case in our study.Overall, our study supports the notion that floorball is a relatively safe team sport. Only 13 players had to be brought in by ambulance, whereas four out of five patients came on their own. Seventy-nine percent of the patients were assessed as “urgent” (examination within 30 min needed) or “less urgent” (examination within 90 min needed). Additionally, 19.01% were declared as “highly urgent” (examination within 10 min needed), and only four needed immediate examination. These four cases consisted of one cardiac arrest, two HWS distortion with hypesthesia, and one trauma to the larynx, and all but the cardiac arrest could be sent home. Furthermore, 93.16% of the patients could be discharged home, while 6.08% had to be hospitalized. Four (4) of the hospitalized patients were in need of immediate surgery. Two had one or more fractures of the lower jaw, one had a femoral neck fracture, and one developed erysipelas after a knee wound, which had to be cleaned out.We found that the mean cost of all our cases was CHF 1191.43. This value only incorporates expenses created during the patients’ stay at our university hospital, without follow-up costs. Unsurprisingly, the main cost-generating factor was whether the patient had to be hospitalized, with all 16 hospitalizations generating costs greater than CHF 2000. The most represented type of injury in this category was eye injuries, with 5 of those 22 patients having some kind of eye-related problem, which is of course associated with the sheer number of eye injuries, but nevertheless shows that eye injuries are far from trivial accidents.Protective eyewear in floorball should be mandatory for young adults until at least the age of 16 years. Extending the age limit further and encouraging eyewear in non-organized practise should be seriously considered .As there are numerous injuries to the lower extremities, prevention should be focused on acute ankle and knee injuries. Avramakis et al. suggest that high-shanked shoes with low soles reduce supination in the ankle joint .The impact of dental injuries and therefore the knowledge of first aid and the benefit of wearing mouth guards in floorball should be further investigated.More effort is needed in analyzing the biomechanics behind specific movements in floorball, as this leads to a better understanding of the different injury mechanisms.Once this has been achieved, different equipment should be examined to find the optimum compromise between good performance and good protection.The main focus for injury prevention has been laid on competitive sport. As the popularity of floorball grows, further efforts should go into comparing competitive and unorganized play in order to establish whether there are different profiles of injuries and risks and whether preventive measurements in competitive floorball also work in mass sports.Our results suggest that there are several possible ways to improve the journey from injury to recovery, which would benefit injured floorball players. We now propose the following suggestions for preventing injury:This retrospective analysis has several limitations. The Ecare health record system only used floorball accidents treated in the emergency department of Berne University Hospital. Thus, floorball injuries treated in other emergency departments or private physicians’ practices were not recorded. Therefore, the number of floorball injuries is of limited general validity, due to the small sample size. The findings of this study may not be representative of floorball-related injuries treated in other types of healthcare facilities or those injuries that received no medical treatment (for example contusion of the ankle). On the contrary, a very large number of treatments for eye injuries can be due to the fact that the eye is a sensitive organ and should be examined immediately by a specialist. Narrative data were used to identify floorball-related accidents. The narrative portion of the Ecare health record system database frequently lacks relevant details of the patient’s history and outcomes , which may lead to errors in selection or interpretation. There are no true exposure data in this study, and this also limits the interpretation of its findings. However, these analyses of people with floorball-related injuries does identify information on diagnosis, lesion site and the mechanism of injury leading to accidents. These deserve further investigation, and this may help to prevent these injuries.These analyses have presented a unique insight into Swiss floorball injuries. Strategies to prevent injuries should be developed. The results demonstrate that injuries to the lower extremities and eyes are quite a common problem among floorball players. Since floorball still causes many eye injuries and using protective eyewear reduces the risk of eye trauma, we strongly recommend that floorball players of all age groups wear protective eyewear and suggest that the Swiss floorball association (Swiss Unihockey) mandates its use.The present analysis is a first step towards identifying risk factors. On the basis of this study, further systematic investigations should be conducted. Including data from the whole country, with the objective of achieving in-depth knowledge of the mechanism and clinical course of floorball-related injuries. To enhance the comparability of the studies and improve classification, standardized assessment tools should be used in the future, and all accidents, including minor incidents without medical care, should be recorded in a register for each team.Further prospective studies could focus on the monetary impact to the economic system when patients cannot work after floorball accidents, as well as to the healthcare system in general. The financial aspects of this increasingly popular sport would then become clearer.