Oral cholera vaccine found safe in Indian children

New double-dose oral cholera vaccine offers cover for 2 years  for both children and adults

A cholera vaccine, which can be administered through the mouth, has been proven safe and effective in Indian children.

New oral cholera vaccine, currently being developed by International Vaccine Research Institute (IVI) in Seoul, South Korea, and produced by Shantha Biotechnics in India meets World Health Organization standards and can be made available in India soon.

Oral cholera vaccine study involving 107,774 participants in Kolkata in eastern India, has been found safe and effective in Indian children, where the infectitious disease cholera is much more prevalent.

Oral cholera vaccine given to the study participants in two doses, at least 14 days apart.
After continuous monitoring for over two years, the researchers found there were 20 episodes of cholera in the vaccine group and 68 episodes in the placebo group.

The results indicate that oral cholera vaccine had a protective efficacy rate of 67 percent, the researchers said.

No side-effects or adverse events were reported during the trial period of oral cholera vaccine.

Oral cholera vaccine offered protection in children vaccinated at ages under 5 years, as well as in older individuals.

“This … trial shows that the modified killed-whole-cell oral vaccine is safe and efficacious, providing nearly 70 percent protection against clinically significant cholera for at least 2 years after vaccination,” wrote the researchers, led by John Clemens at the International Vaccine Research Institute (IVI) in Seoul, South Korea.

IVI’s earlier version of cholera vaccine used in Vietnam was abandoned because of some manufacturing process issues.

Later on IVI improved the oral cholera vaccine by working with Vietnamese manufacturer VaBiotech and transferred its production  to the WHO-approved vaccine maker Shantha Biotechnics in Hyderabad in India.

The Drugs Controller General of India, the apex body which regulates the quality of drugs sold in India, has already licensed the new oral cholera vaccine.

Diarrhoeal diseases account for an estimated 600,000 deaths each year in children aged under 5 years in India.

Oral cholera vaccine offers two-year-immunity.

The only WHO-prequalified oral cholera vaccine to date is the double dose Swedish vaccine called Dukoral. It is very expensive — around Rs 1250 a dose — and needs to be co-administered with a relatively large volume of buffer solution.

India used to administer an injectible vaccine in the 1970s when cholera was a notifiable disease. However, in 1973, its use was scrapped as it was only 30% effective and provided immunity only for eight months.

The oral cholera vaccine is very innovative as it incorporated all the important genes required to make it very selective and more effective without harming the intestines in any way. It is designed to prevent even severe infections caused by various mutants of the cholera virus.