CHOLERA

• Researchers identified the decline of antimicrobial resistance in Cholera-Causing Bacteria.
• 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.
• 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.

Symptoms:

1. Profuse watery diarrhoea
2. Vomiting
3. Leg cramps

Transmission:

• 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.

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.

SOURCE: THE HINDU,THE ECONOMIC TIMES,MINT