Epidemiologic Aspects of a Foot- and-Mouth Disease Epidemic in Cattle in Ecuador
A case-control study was conducted to identify herd-level risk factors associated with foot-and-mouth disease (FMD) in Ecuador. Case herds were those with presence of cattle with clinical signs of FMD and that tested positive for FMD virus during the epidemic of 2002 (n = 39). Control farms (n = 78) were selected randomly from a list of farms without a history of FMD. All study farms were visited, and managers were interviewed to complete an epidemiologic questionnaire. Feedlot operations, purchase of livestock at markets, and close proximity to markets or slaughter facilities were identified as risk factors for FMD (P ≤ 0.01). In addition to systematic vaccination of the national herd, we recommend allocation of funds for ring-vaccination of cattle herds in close proximity to markets or slaughter facilities, and to enforce movement of vaccinated-cattle only to help control and prevent new epidemics of FMD.
Risk factors for recurrence of FMD outbreaks in Iran: a case-control study in a highly endemic area
BackgroundFoot-and-mouth disease (FMD) is an acute viral disease of cloven-hoofed animals with high economic impact. FMD remains endemic in Iran particularly in the livestock-dense province of Khorasan Razavi in northeastern Iran where FMD outbreaks continuously occur. In this study, we aimed to quantify risk factors for the recurrence of FMD outbreaks in Iran by analyzing a time-series of FMD outbreak data from the province of Khorasan Razavi.ResultsThis study used FMD outbreak data collected from 2012 to 2014. Data were collected by local offices of the Iranian Animal Disease Department and the veterinarian of the veterinary council of the Khorasan Razavi province. An outbreak investigation questionnaire was delivered to 127 farms, including 46 case farms (FMD-infected) and 81 control farms (FMD-free). To quantify and compare the odds of exposure to a risk factor in FMD-infected farms versus FMD-free farms, logistic regression models were built using SPSS software version 16.Our results of multivariable logistic regression indicate that hygienic status of the farm (OR = 11.83; CI = 3.38–41.43), FMD vaccination status (OR = 0.06; CI = 0.01–0.68), transportation of livestock (OR = 0.40; CI = 0.163–0.981) and inhibition of livestock dealers’ entry into the farm (OR = 0.36; CI = 0.12–1.09) were identified as important risk factors for farm-level FMD infection.ConclusionThis study generated much needed evidence on a set of modifiable risk factors for the recurrence of FMD outbreaks in the high risk province of Khorasan Razavi. This information can be used to improve existing national FMD control program and suggest new guidelines to prevent FMD outbreaks in the country.
A SAS® CODE TO CORRECT FOR NON-NORMALITY AND NON-CONSTANT VARIANCE IN REGRESSION AND ANOVA MODELS USING THE BOX–COX METHOD OF POWER TRANSFORMATION
A computer program written in SAS ® code for theBox–Cox family of powertransformations is presented. The purpose of the program is tosuggest a powertransformation for the positive continuous response variablesin only regression and ANOVAmodels. A brief overview of data transformation in regressionand analysis of variance is given.An example using real data from the U.S. EnvironmentalProtection Agency‘sEnvironmental Monitoring and Assessment Program/Estuaries(EMAP-E) illustrates the useof the program.