- 27 Jul 2022
- 3 min read
Why in News?
Researchers identified the decline of antimicrobial resistance in Cholera-Causing Bacteria.
What are the Findings?
- More than two hundred serogroups of Cholera bacterium are known, of which only O1 and O139 Genomes are known to cause such infection that leads to epidemics and pandemics.
- Researchers studied the genome of O139 and traced the reason for its dying down after taking over from O1.
- Two key genomic evolutionary changes took place in O139, the first related to the type of cholera toxin it produced and the second related to a loss of Antimicrobial Resistance (AMR).
- Two main modifications were in the cholera toxin genes and in the Antimicrobial Resistance (AMR) portfolio.
- With the reduction in AMR capacity of O139, it potentially lost its competitive advantage against the O1.
What is Cholera?
- It is a life-threatening infectious disease and a public health hazard.
- Cholera is an acute, diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae.
- The infection is often mild or without symptoms, but sometimes can be severe.
- Profuse watery diarrhoea
- Leg cramps
- A person may get cholera by drinking water or eating food contaminated with the cholera bacterium.
- The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water.
- Currently there are three WHO pre-qualified oral cholera vaccines (OCV), Dukoral, Shanchol, and Euvichol-Plus.
- All three vaccines require two doses for full protection.
What are the Recommendations?
- Continuous surveillance is necessary to monitor if any of the serotypes and serogroups are gaining antibiotic resistance over time and may become major outbreak lineages at any time.
- To stay ahead of the curve and ensure best public health outcome, it is important that vaccines and treatments are regularly re-evaluated for efficiency to any newly evolving variants.