NextBillion - An Initiative of the William Davidson Institute at the University of Michigan

Wednesday, October 26, 2016

The World Health Organization (WHO) is considering whether to use just one of the usual two doses of a cholera vaccine in Haiti to vaccinate more people, albeit with a shorter protection period.

The U.N. agency announced earlier this month that it would send 1 million doses of cholera vaccine to the Caribbean island. More than 200 cases of the deadly disease have been reported since Hurricane Matthew, and the numbers are expected to surge as the rainy season progresses between November and January.

The one-dose method will be 87.3 percent effective in reducing cholera for up to two months, according to a new study conducted in Juba, South Sudan, by Doctors Without Borders (MSF). The researchers administered the Shanchol vaccine to 160,000 people – the first time a single dose of oral vaccine had been used in a mass vaccination campaign.

“The results of the study are very promising,” said Iza Ciglenecki, MSF operational research coordinator, in a press release. “More research is needed, and we still don’t have full knowledge of the length of the coverage after two months. Nevertheless, this could be a milestone in cholera protection, as it may allow for the prevention of unnecessary illness and death during outbreaks. Given the lack of available vaccines, this is very good news.”