The federal agency supports a vaccine fast-tracked by the FDA for adults traveling to one of the more than 50 countries where cholera is endemic.
The Centers for Disease Control and Prevention (CDC) is now recommending that adults traveling to areas of active cholera transmission receive a recently-approved, single-dose oral vaccine.
The vaccine was approved by the U.S. Food and Drug Administration in 2016 after a fast-track and priority review designation. The CDC’s Advisory Committee on Immunization Practices (ACIP) finalized its recommendation in May, making it the only U.S.-approved vaccine against cholera. Three other vaccines are recommended by the World Health Organization (WHO) but are not available in the United States.
Cholera is a bacterial infection that causes severe diarrhea and dehydration. Spread through contaminated water supplies and poor hygiene, cholera is active in more than 50 countries around the world, predominantly in Africa and India, according to WHO.
The vaccine is not generally recommended for most travelers in the U.S. since they don’t frequently travel to areas of active cholera transmission, according to ACIP, but there was an increase in reported cases among U.S. travelers to Haiti after a 2010 hurricane. Cholera is also endemic in several top destinations for U.S. travelers, including China, the Dominican Republic, India, Jamaica and the Philippines. No countries currently request cholera vaccination for travel.
The vaccine does not replace prevention measures like utilizing safe food and water and practicing good hygiene, but it does reduce the chances of severe diarrhea by 90% at 10 days after vaccination and by 80% at three months after vaccination, according to ACIP. The vaccine has not been testing in women who are pregnant or breastfeeding, and research has not yet identified how effective the vaccine is three to six months after vaccination. Side effects include tiredness, headache, abdominal pain, nausea and vomiting, lack of appetite and diarrhea.
Brittany Behm, MPH, a public affairs specialist in the division of foodborne, waterborne, and environmental and the national center for emerging and zoonotic infectious diseases at CDC said the agency has not tracked how many orders have been placed or how many vaccines have been administered since the vaccine’s approval, and that it’s too soon to judge the efficacy of the vaccine.
“It is very early to assess whether the vaccine has resulted in a reduction in cholera infections in the U.S. This kind of assessment is also very difficult, because cholera is very rare in U.S. travelers and the number of cases that are reported depend on many factors, including cholera activity in other countries, travel patterns, vaccine uptake and diagnostic and reporting practices,” Behm told Medical Economics. “Most travelers from the United States do not visit areas with active cholera transmission and are rarely at risk.”
Areas of active transmission are classified as such only when cases are regularly found or an epidemic is in progress, not when rare cases are reported, said Behm.