A cholera outbreak in South Sudan’s Jonglei state has affected nearly 1,500 people, says the UN. International agencies are rushing to stem the spread of the water-borne disease. One of the tools recommended to keep people healthy is a cholera vaccination campaign. It is boosted by recent research showing that it is highly effective at protecting people against cholera.
“We’ve got to move quickly to deliver vaccinations against cholera that can protect 60 to 80 percent of those who are potentially infected,” said Antoine Foucher, Doctors Without Borders head of mission in Ethiopia, in a press release on Wednesday.
It a very different story from what happened in Haiti. When the idea of using a vaccine to respond to Haiti’s cholera outbreak was proposed by Partners in Health in 2011, the Haitian government balked. The need to treat people immediately, a lack of resources and the early failures to create an adequate vaccine were behind the reluctance expressed by the government and some public health officials.
It took the election of a new president in late 2011, roughly a year after the outbreak started, for vaccination plans to start. The news that Partners in Health would be running a nearly $1 million cholera vaccine pilot in Haiti was met with immediate concerns. Medical relief organization Doctors Without Borders was concerned that it would divert what little resources were already available to deal with the outbreak.
“Money spent on vaccines should not come at the expense of money spent on permanent water and sanitation measures,” said Dr. David Olson, MSF medical advisor for diarrheal diseases, in a October 2011 press release.
“At the time of outbreaks in Haiti in late 2010 and mid 2011, Shanchol, the best vaccine for use in this context, was not yet approved by the WHO,” said Olson in a statement to Humanosphere. “Even if MSF had used the unqualified vaccine, the available supply at the time would only have covered 1.5 percent of the Haitian population.”
The argument made by Partners in Health and its supporters was that ridding Haiti of cholera, preventing people from catching it and treating those already with it required a series of interventions all at once. One of those was a vaccine. Two and a half years later, a new study from Guinea shows that an oral cholera vaccine was able to protect people by 86%.
Ironically, the study was carried out by researchers working with Doctors Without Borders. The research not only validates the initial recommendations by Partners in Health, but it provides hard evidence that a vaccine can help during the onset of a cholera outbreak.
“Now we know that oral cholera vaccine confers a high level of protection in outbreak settings, and that vaccinating against this highly deadly disease can and should be one thing we do when we have a cholera epidemic on our hands, in addition to other preventive and control measures,” said Francisco Luquero, lead researcher of the study.
A total of 200 patients were enrolled in the study between June and October of 2012. Two doses of the cholera vaccine Shanchol was given to 40 people. The analysis, published last month in the New England Journal of Medicine, showed that people who received the two doses were less likely to experience acute diarrhea, the main and most deadly symptom of cholera.
The vaccine is particularly useful in places where cholera outbreaks do not normally occur, like Haiti, Guinea and South Sudan. Partners in Health managed to reach 100,000 people in Haiti through its pilot program. They only evaluated the people who received the vaccine, but the evidence collected shows that it is helping to provide protection.
“You are not going to eliminate cholera by using a vaccine, but you have to use all the tools available, including vaccines,” said Dr Louise Ivers, Senior Health and Policy Advisor for Partners In Health .
The larger issue of poor sanitation and hygiene will always be a hurdle to preventing cholera. As anyone who played the video game Oregon Trail knows, cholera (and dysentery) used to be a problem right here in the US. It is no longer an issue do in large part to the fact that we drink clean water and have ready access to bathrooms. In the case of Haiti, the focus on cholera is also an opportunity to fix the bigger problems.
“The sanitation is so desperate in Haiti, but it hasn’t substantially changed,” said Ivers. “I see the cholera epidemic of as an opportunity for Haiti to take advantage of the attention and make proper investments in water, sanitation and healthcare.”
As for the vaccine, more research is underway to see what dosage levels are effective. Ivers says there is some evidence that a single dose may work in cholera burdened countries, like Bangladesh and India, but two doses work better where cholera does not regular occur. More research will be needed to actually prove what is the best way to use the vaccines in differing situations.
Better research, WHO approval and more supply of the Shanchol vaccine makes it an important tool in emergency cholera response. What is now no longer up for debate is using a cholera vaccine in the first place.
