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BBB - Vibrio parahaemolyticus

Bad Bug Book:
Foodborne Pathogenic Microorganisms and Natural Toxins Handbook
Vibrio parahaemolyticus

A new version of the Bad Bug Book was released in 2012, below is a previous version.

1. Name of the Organism:

Vibrio parahaemolyticus (and other marine Vibrio spp.**)

This bacterium is frequently isolated from the estuarine and marine environment of the United States. Both pathogenic and non-pathogenic forms of the organism can be isolated from marine and estuarine environments and from fish and shellfish dwelling in these environments.

2. Nature of Acute Disease:

V. parahaemolyticus-associated gastroenteritis is the name of the infection caused by this organism.

3. Nature of Disease:

Diarrhea, abdominal cramps, nausea, vomiting, headache, fever, and chills may be associated with infections caused by this organism. The illness is usually mild or moderate, although some cases may require hospitalization. The median duration of the illness is 2.5 days. The incubation period is 4-96 hours after the ingestion of the organism, with a mean of 15 hours. Disease is caused when the organism attaches itself to an individuals' small intestine and excretes an as yet unidentified toxin.

Infective dose -- A total dose of greater than one million organisms may cause disease; this dose may be markedly lowered by coincident consumption of antacids (or presumably by food with buffering capability).

4. Diagnosis of Human Illness:

Diagnosis of gastroenteritis caused by this organism is made by culturing the organism from the diarrheic stools of an individual.

5. Associated Foods:

Infections with this organism have been associated with the consumption of raw, improperly cooked, or cooked, recontaminated fish and shellfish. A correlation exists between the probability of infection and warmer months of the year. Improper refrigeration of seafoods contaminated with this organism will allow its proliferation, which increases the possibility of infection.

6. Relative Frequency of Disease:

Major outbreaks have occurred in the U.S. during the warmer months of the year. Sporadic cases occur along all coasts of the U.S.

7. Course of Disease and Complications:

Diarrhea caused by this organism is usually self-limiting, with few cases requiring hospitalization and/or antibiotic treatment.

8. Target Populations:

All individuals who consume raw or improperly cooked fish and shellfish are susceptible to infection by this organism.

9. Food Analysis:

FDA's Bacteriological Analytical Manual Vibro parahaemolyticus

Methods used to isolate this organism from foods are similar to those used with diarrheic stools. Because many food isolates are nonpathogenic, pathogenicity of all food isolates must be demonstrated. Although the demonstration of the Kanagawa hemolysin was long considered indicative of pathogenicity, this is now uncertain.

10. Selected Outbreaks:

For more information on recent outbreaks see the Morbidity and Mortality Weekly Reports from CDC.

11. Education and Background Resources:

Literature references can be found at the links below.

Loci index for genome Vibrio parahaemolyticus

Available from the GenBank Taxonomy database, which contains the names of all organisms that are represented in the genetic databases with at least one nucleotide or protein sequence.

US. FDA  Risk Assessment for Vibrio parahaemolyticus

In response to the 1997 and 1998 outbreaks of V. parahaemolyticus infections in the United States, the Food and Drug Administration (FDA) conducted a risk assessment to characterize the public health impact associated with consumption of raw oysters harboring pathogenic V. parahaemolyticus. This risk assessment focused specifically on oysters, because this was the food predominantly linked to the outbreaks. The risk assessment structures our knowledge of V. parahaemolyticus in a systematic manner, and includes sophisticated, mathematical models developed to estimate exposure to this microorganism and the dose-response relationships between the consumer and V. parahaemolyticus.

Page Last Updated: 08/20/2015
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