 the most dominant type and serotype Ogawa was found continuous in circulation throughout the year which has caused recent cholera outbreaks in India during the past years. Phage sensitivity data propose an alternative cost-effective approach to prevent cholera outbreak by therapeutic uses of typing phages irrespective of origin or clonality of the strains.
Keywords: ElTor, O1, Ogawa, phage typing, S5 phage, Vibrio cholera
|How to cite this article:|
Chakrabarti AK, Biswas A, Tewari DN, Mondal PP, Dutta S. Phage types of Vibrio cholerae 01 biotype ELtor strains isolated from India during 2012–2017. J Global Infect Dis 2020;12:94-100
|How to cite this URL:|
Chakrabarti AK, Biswas A, Tewari DN, Mondal PP, Dutta S. Phage types of Vibrio cholerae 01 biotype ELtor strains isolated from India during 2012–2017. J Global Infect Dis [serial online] 2020 [cited 2021 Jan 23];12:94-100. Available from: https://www.jgid.org/text.asp?2020/12/2/94/284623
| Introduction|| |
Cholera remains a significant global health burden and is endemic in many parts of the third world countries due to inadequate sanitation and safe drinking water resources mainly during the rainy season.Vibrio cholerae, an extremely motile, halophilic, curved shaped, Gram-negative bacterium is known for causing profound acute secretory diarrhea, cholera. Although V. cholerae is a natural member of aquatic environments, only a small fraction of environmental strains are capable of causing the disease. Among the several known serogroups, only two serogroups, V. cholerae O1 and O139 can produce cholera toxin and V. cholerae O1 often accountable for causing the vast majority of the disease including recent cholera outbreaks throughout the world. Serogroup O1 consists of biotypes ElTor and classical with distinct phenotypes. Both the biotypes carry two serotypes, Inaba and Ogawa with different disease characteristics. Cholera has a long history; in the past 200 years, seven cholera pandemics have killed millions across the globe including the Indian subcontinent (specifically in Gangetic Bengal). After several devastating pandemics in the different corners of the globe, the seventh pandemic which originated in Indonesia is still ongoing., Most recent cholera outbreaks caused by V. cholerae O1 occurred in Haiti, causing at least 8,183 deaths and above 665,000 cholera incidences till date (https://www.cdc.gov/cholera/haiti/index.html#two). Global estimates suggest that every year 1.3 million to 4.0 million cases of cholera are responsible for 21,000–143,000 deaths. In India, 27,615 cholera cases were reported between 2010 and 2015, reflecting the sustained presence of V. cholerae O1 in the country and cholera is considered to be one of the underreported pathogens throughout the world.
Several serotypes of V. cholerae strains harbor variety of bacteriophages, and these are beneficial from the clinical viewpoint with the command to control the bacterial population leading to controlling the disease.,, Vibrio phage plays a critical role in the evolution of pathogenic V. cholerae by mediating horizontal transfer of clusters of virulence genes, genomic rearrangements, as well as by bactericidal selection. Lysogenic filamentous phage, CTXϕ, is capable of transferring cholera toxin genes to nontoxigenic strains leading to the conversion of nontoxigenic strains to toxigenic strain.,, The presence of cholera bacteriophages was found inversely associated with the occurrence of viable V. cholerae in the aquatic environment which was found in correlation with the number of locally reported cholera cases. Lysogenic phage present in some environmental V. cholerae strains of both epidemic and nonepidemic serogroups has the power to kill the epidemic strains and thus contributes to the control of the disease.
Different bacteriophages have been used to distinguish pathogenic strains of bacteria from clinical isolates based on their phage susceptibility. Due to their natural specificity, ease of maintenance and straightforward production, phage owns several desirable characteristics which ma