Over the weekend, CNN and others reported that 3 cases of cholera were confirmed in New York City. Although such cases occur at a rate of about one a year, and usually in travelers returning from far-flung countries where cholera is endemic, such cases are relatively rare in most developed countries. But few diseases conjure up as many images of filth and old-worldliness as cholera. It was one of the first diseases to have spread globally at epidemic proportions. The famed John Snow basically invented epidemiology as a result of an outbreak of the disease in London. And it is hard to think about the disease without thinking of sewage, excrement, and refuse. Surely in this day and age that is a disease that is on its way out, right?
Wrong. It turns out that cholera is once again spreading around the world at “epidemic proportions”. I did not realize this myself until recently – perhaps because this “epidemic” has in fact been underway for over four decades! Cholera is on the rise, even here in the United States, and has attracted some media of attention of late *thanks* to the outbreaks that have occurred in Haiti and Zimbabwe. Despite the relative ease at which cholera can be treated with relatively simple, inexpensive, and accessible remedies, it remains one of the most acutely lethal pathogens in the world. Cholera’s killing power comes from how quickly it can kills otherwise seemingly healthy individuals: it regularly kills its victims within 12-24 hours of the onset of symptoms. People die before effective treatments can be delivered. Roughly 200,000 people are stricken every year from the disease of which there are usually about 5,000 deaths (Haiti alone has bumped up the numbers for 2010).
Although not a major contributor to the overall burden of disease, one could argue that this long-running epidemic should really be seen as a failure of global health: we know how to prevent it, we have effective vaccines to prevent its transmission, and we have effective treatments available to treat it. Yet it remains. This fact has led others to wonder if we are really doing enough to address this really long-running (and runny) mess. The basic strategy to date has been the promotion of oral rehydration solution (ORS) and education to help raise the awareness of its symptoms. Despite the fact this strategy has probably help saved dozens of millions of lives, it may not be enough, and it has a number of experts asking whether or not we are really doing enough. Is it time for a new global strategy for cholera?
Given that effective vaccines exist, should we considering immunizing more people against cholera? A good example of where such stepped up immunization programs might be warranted would be during an outbreak, such as the one observed recently in Haiti. The arguments against such programs has always been that since the vaccines take a while to become effective and given the difficulties associated with implementing these programs (typically during a period of chaos) these programs are unlikely to be effective. However, model based estimates have recently shown that such programs might in fact still be effective even under relatively slow response scenarios. Also, another recent article has shown that the use of such vaccines after an outbreak in Hanoi were also highly effective.
Of course, the cost-effectiveness of vaccinations vs. alternative approaches should be considered, prevention and treatment should not be considered substitutes, and long-term thinking will ultimately be what is needed to address this scourge but it does raise some interesting and vitally important questions (it also makes me think a lot about efforts to eradicate polio). In this case, 50 years into the epidemic, at what point can we say that we are not doing enough?Share on Facebook