Infectious Disease News, November 2017
Donald Kaye, MD, MACP
According to WHO, Vibrio cholerae causes 1.3 to 4 million infections and 21,000 to 143,000 deaths worldwide each year. The disease incidence and severity disproportionately affect children aged younger than 5 years. Cholera is spread by water or food contaminated with human feces from a person with active cholera or from a person who is convalescing from cholera or has had asymptomatic or mildly symptomatic cholera. Following cholera infection, excretion of the organism can last for at least 2 weeks. Estimates of the ratio of asymptomatic to symptomatic people range from 3:1 to more than 100:1. The bacterium can also survive in the environment in brackish rivers and coastal waters for long periods.
Cholera is endemic in Africa, South Asia and Southeast Asia. It is a disease that affects only humans. In modern times, there have been periodic flares of epidemics in these and other areas. Most recently, there have been large epidemics in Haiti, where in 2010 the organism was introduced following an earthquake, and now in Yemen, where there is an ongoing war. Epidemics are precipitated and enhanced by circumstances that interfere with sanitation and the state’s ability to supply safe water. These circumstances include earthquakes, war and flooding.