Noncholera vibrio infections

[Mary Mallozziberg]

Noncholera vibrios include the gram-negative bacteria Vibrio parahaemolyticus, V. mimicus, V. alginolyticus, V. hollisae, and V. vulnificus; they may cause diarrhea, wound infection, or septicemia. Diagnosis is by culture. Treatment is with ciprofloxacin or doxycycline .

Noncholera vibrios are sometimes called nonagglutinable vibrios (ie, they do not agglutinate with serum from cholera patients). They typically inhabit warm salt water or mixed salt and fresh water (eg, in estuaries).

V. parahaemolyticus, V. mimicus, and V. hollisae usually cause food-borne outbreaks of diarrhea, typically involving inadequately cooked seafood (usually shellfish).

V. parahaemolyticus infections typically occur in Japan and in coastal areas of the US. The organisms damage intestinal mucosa but do not produce enterotoxin or invade the bloodstream. Also, wound infection may develop when contaminated warm seawater enters a minor wound.

V. alginolyticus and V. vulnificus can cause serious wound infection; neither causes enteritis. V. vulnificus, when ingested by a compromised host (often someone with chronic liver disease or immunodeficiency), can cross the intestinal mucosa without causing enteritis and cause septicemia with a high mortality rate; occasionally, otherwise healthy people develop such infections.