Photo credit: Corbis
We don’t hear a lot about cholera any more, but as the cholera epidemic that broke out last year in Zimbabwe has shown us, most developing countries are still vulnerable to occasional breakouts and in places in Asia, where cholera is still endemic, it is still causing significant illness. Over 200,000 thousand cases of the disease were reported worldwide in 2006, and this is only thought to represent a small fraction (5-10%) of the actual number of cases of the disease. It is estimated that over 100,000 people die of cholera every year, roughly 1/8 the number that die from malaria, mostly children under the age of 5. Wars, natural disasters, and economic collapse (as witnessed in Zimbabwe) can mean the disease can strike anywhere, anytime.
In theory, we have a vaccine for cholera, however, in practice the vaccine that has been on the market for many years is rarely used. The current vaccine is considered too expensive, too difficult to administer, and has the potential for side effects. As such, it is rarely used in public health programs.
A funny anecdotal story about this vaccine is that years ago, there were rumors that some customs officials used to dupe tourists into paying bribes by claiming that cholera vaccination was necessary to enter the country. Since the vaccine was never given to tourists, people who did not know better would have to pay up. My travel clinic in Montreal used to just certify that we had been given it (still in my vaccine card today) when in fact we had not.
Results of a clinical trial conducted in India have shown that we might be closer to having a safe, inexpensive, and effective vaccine against cholera in the coming years. The trial showed that the vaccine was about 67% effective at reducing cases of cholera when two doses were properly given, and was also protective in children, those most at risk of cholera. The vaccine is far from perfect, and the long term protective effect of the vaccine has not been established, but it is a good and promising start.
This trial also represents an important victory for some of the new drug discovery and development models that have come on board in recent years. This is not likely to be a lucrative market for any drug company, so it had to be done in partnership. Thanks to the Gates Foundation, the Swedish International Development Corporation Agency, and others this work was all possible.Share on Facebook