CholeraVibrio cholerae bacterium. These bacteria are typically ingested by drinking water contaminated by improper sanitation or by eating improperly cooked fish, especially shell fish. Symptoms include diarrhea, abdominal cramps, nausea, vomiting, and dehydration. It is treated with rehydration and antibiotics, but in severe cases, cholera can lead to death.
- About one million Vibrio cholerae bacteria must be ingested to cause cholera in normally healthy adults, although increased susceptibility may be observed in those with weakened immune systems, individuals with decreased gastric acidity (as from the use of antacids), or those who are malnourished.
- The last major outbreak of cholera in the United States was in 1911.
- 1,099,882 cases and 10,453 deaths were reported in the Western Hemisphere between January 1991 and July 1995.
- On average, one case of cholera is reported in the United States every week.
The point of this is that the resulting diarrhea allows the bacterium to spread to other people under unsanitary conditions.
Carriers of the cystic fibrosis gene are protected from the severe effects of cholera because they don't lose water as fast. This explains the high incidence of cystic fibrosis among populations which were formerly exposed to cholera.
Recent genetic research has determined that a person's susceptibility to cholera (and other diarrheas) is affected by their blood type. Those with type O blood are the most susceptible. Those with type AB are the most resistant, virtually immune. Between these two extremes are the A and B blood types, with type A being more resistant than type B.