Decreased cholera incidence in Haiti a natural course of epidemic

**Andrews JR. Lancet. 2011.doi:10.1016/S0140-6736(11)60273-0.**

Issue: April 2011

Results from an epidemic model of cholera transmission suggest the decline in the prevalence of cholera in Haiti during early 2011 was part of the natural course of the epidemic and, therefore, “should not be interpreted as indicative of successful intervention.”

Jason R Andrews, MD, of the division of infectious diseases at Massachusetts General Hospital at Harvard Medical School, and Sanjay Basu, MD, of the department of medicine at the University of California San Francisco, suggest increased vaccination, distribution of clean water and availability of antibiotics could have a significant impact on the epidemic.

The projections of future morbidity and mortality of the cholera epidemic in Haiti were published in The Lancet. Incidence data were pooled on cholera cases in Haiti between Oct. 31, 2010 and Jan. 24, 2011. Future epidemic trajectories were then generated to assess the effect of vaccination, increased antibiotic distribution and clean water between March 1 and Nov. 30, 2011.

The model projected that 779,000 cases of cholera and 11,000 deaths would occur in Haiti between March 1 and Nov. 30, 2011.

However, when considering a 1% decrease in the consumption of contaminated water, 105,000 cases of cholera and 1,500 deaths would be avoided. In addition, 63,000 cases and 900 deaths could be averted if only 10% of the population were vaccinated. The distribution of antibiotics to people with severe dehydration and just half of those with moderate dehydration would also avoid thousands of deaths, according to the researchers.

“By contrast with the United Nations projection of 400,000 cases of cholera between 2010 and 2011, our dynamic model of cholera…projected more than 750,000 cases within 9 months,” the researchers wrote. “The alternative available for Haiti is a best guess, which ignores disease rates at present or cholera pathogenesis and transmission, and might underestimate the resources needed to avert future cases and deaths.”

Follow the PediatricSuperSite.com on Twitter.