Regulators in the United States have approved the first vaccine intended to protect American travelers from becoming infected with cholera.
In their announcement on June 10th, the Food and Drug Administration (FDA) say the
The vaccine – called Vaxchora – is the only FDA-approved vaccine for the prevention of cholera, a potentially life-threatening disease that is easily prevented and treated.
The live, weakened vaccine is taken as a single, oral, 3 fl oz (85 ml) liquid dose no less than 10 days before traveling to a cholera-affected area.
Cholera is a disease spread by the fecal-oral route – commonly caused by ingesting water or food contaminated with Vibrio cholerae bacteria.
The disease is rare in the U.S. and other industrialized nations. It occurs in parts of the world where sanitation is poor and water and sewage treatment is inadequate. These areas include parts of Africa, Southeast Asia and Haiti.
Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, says the approval of Vaxchora “represents a significant addition to the cholera-prevention measures currently recommended by the Centers for Disease Control and Prevention for travelers to cholera-affected regions.”
Often, infection with cholera is mild, causing a watery diarrhea. However, severe cholera can result in profuse diarrhea and vomiting, causing dehydration.
When treated rapidly, people infected with cholera can recover quickly, and there are typically no long term consequences. If not treated promptly with antibiotics and fluid replacement, the disease can be life-threatening.
According to the World Health Organization (WHO), serogroup O1 is the strain that causes the majority of cholera outbreaks worldwide.
- Cholera is estimated to cause
1.4-4.3 million cases and 28,000-142,000 deaths worldwide every year - The disease can kill within hours if left untreated
- Up to 80% of cases can be successfully treated with oral rehydration salts.
The efficacy of the vaccine was tested in a randomized, placebo-controlled trial involving 197 U.S. residents aged 18-45.
The trial results showed the vaccine was 90 percent effective when given 10 days before ingestion of cholera bacterium and 80 percent effective when given 3 months before exposure.
Other trials were conducted in the U.S. and Australia to assess immune system response to the vaccine. These showed that in adults aged 18-45 years, 93 percent of vaccine recipients produced anti-cholera antibodies, and in adults aged 46-64, the figure was a slightly lower 90 percent.
The effectiveness of the vaccine in protecting people living in cholera-affected areas has not been established, note the FDA.
Trials of vaccine safety show that the most common reactions to the vaccine include tiredness, abdominal pain, headache, nausea, vomiting, lack of appetite, and diarrhea.
PaxVax Bermuda Ltd. of Hamilton, Bermuda, make the vaccine.