Vaccine on the anvil
india may soon come out with a vaccine against cholera. The first and second phase of clinical trials for a recombinant oral vaccine, completed recently, have shown a good immunological response, according to a release by the department of biotechnology.
Preparations are now being made for phase- iii clinical trials in Kolkata. Simultaneously, negotiations with industry are also being held to fine-tune, upscale and commercially produce the vaccine if it is found successful in the final trials.
Meanwhile, a study by a team of scientists from the National Institute of Cholera and Enteric Diseases, Kolkata, and the International Vaccine Institute, Seoul, Korea, says mass vaccination could effectively combat seasonal cholera in children. Researchers Dipika Sur and others studied stool samples taken from more than 3,000 children living in slums in Kolkata, who were suffering from diarrhoeal diseases. The scientists concluded that vaccination would help protect children below 5, who are especially vulnerable. The findings appeared in the November, 2005, issue of the journal, Archives of Disease in Childhood (Vol 90, No 11).
But experts say vaccination is not the best way to check cholera. "Mass vaccination for cholera could protect children during outbreaks, but long-term individual protection doesn't seem plausible and cost-effectiveness of the vaccine needs proper assessments,' says Swapan Jana, secretary of the Society for Social Pharmacology, a non-governmental organisation working on public health issues that is based in Kolkata. Agrees Sumana Kanjilal, head of the department of paediatric medicine at Midnapore Medical College Hospital, West Bengal, "Cholera vaccines usually protect patients for short durations only.'