Type your tag names separated by a space and hit enter
Vibrio species (non-cholera)
Official website of the Johns Hopkins Antibiotic (ABX), HIV, Diabetes, and Psychiatry Guides, powered by Unbound Medicine. Johns Hopkins Guide App for iOS, iPhone, iPad, and Android included. Explore these free sample topics:
-- The first section of this topic is shown below --
- Aerobic, Gram-negative, comma-shaped rod (1-3 x 0.5-0.8µm, Fig).
- Grows best in warm, low salinity marine water. Coastal waters/estuaries are ideal. As marine environments warm, these organisms have spread to new areas and are increasingly important causes of human infections.
- Rates of infections in the U.S. have tripled over the past two decades. Estimated to cause approximately 80,000 cases and 100 death each year (most are not laboratory confirmed).
- Most important non-cholera species are V. parahaemolyticus (62% of cases), V. alginolyticus (13%) and V. vulnificus (10% of cases and ~50% mortality).
- Vibrio parahaemolyticus:
- Most common non-cholera vibrio to cause infections.
- Typical presentations:
- GI disease: diarrhea, associated with consumption of contaminated fish/seafood.
- Can also cause skin infections from direct exposure of open wounds to sea water.
- Most environmental strains are non-pathogenic.
- Pathogenic strains carry a hemolysin toxin: thermostable direct hemolysin (TDH) and/or TDH related hemolysin (TRH). Strains with TDH cause hhemolysis on special blood agar plates (kanagawa reaction).
- Vibrio vulnificus: Less common but more lethal. ~95% of seafood associated mortality is related to this organism.
- Part of the normal microbial ecology of estuarine water and mollusks (e.g. in Chesapeake Bay, areas of coast off of Gulf of Mexico).
- Infection can be acquired via ingestion of contaminated seafood or direct inoculation of water onto skin.
- There are 3 recognized biotypes, of which biotype 1 is most important cause of human infection.
- Important toxins are collagenases, metalloproteinases and lipases/phospholipases that lead to tissue destruction, and endotoxin which leads to hypotension and organ failure
- Vibrio alginolyticus:
- Emerging pathogen typically impacting people in coastal communities
- Non-foodborne infections predominate (~86%) and typically affect lower extremity skin or external ears after swimming in warm coastal waters.
- Other occasional Vibrio species causing human infection: V. fluvialis, V. fumissii, V. hollisae, V. damsela, V. cincinnatiensis.
- Cholera is caused by V. cholerae (see that module for details)
- Vibrio parahaemolyticus:
- Obtain from suspected source, e.g., blood (sepsis), wound (wound infection), stool (gastroenteritis).
- Organisms grow well on routine media and in blood cultures.
- Notify micro lab if suspected as cause of gastroenteritis to use special selective media for stool specimen such as thiosulfate citrate bile salt sucrose (TCBS).
- Some labs in endemic areas routinely use this media as part of stool culture protocol during summertime/warmer weather.
- Diagnosis of GI illness due to V. parahaemolyticus is increasingly made via non-culture based (e.g. molecular) assays as part of multiplex panel.