Vibrio parahaemolyticus

From Wikipedia, the free encyclopedia

Vibrio parahaemolyticus
SEM image of V. parahaemolyticus
SEM image of V. parahaemolyticus
Scientific classification
Kingdom: Bacteria
Phylum: Proteobacteria
Class: Gamma Proteobacteria
Order: Vibrionales
Family: Vibrionaceae
Genus: Vibrio
Species: V. parahaemolyticus
Binomial name
Vibrio parahaemolyticus
(Fujino et al. 1951)
Sakazaki et al. 1963

Vibrio parahaemolyticus is a curved, rod-shaped, Gram-negative bacterium found in brackish [1] saltwater, which, when ingested, causes gastroeintestinal illness in humans. [2] V. parahaemolyticus is oxidase positive, facultatively aerobic, and does not form spores. Like other members of the genus Vibrio, this species is motile, with a single, polar flagellum.[3]

Contents

[edit] Pathogenesis

While infection can occur via the fecal-oral route, ingestion of bacteria in raw or undercooked seafood, usually oysters, is the predominant cause the acute gastroenteritis caused by V. parahaemolyticus.[4] Wound infections also occur, but are less common than seafood-borne disease. The disease mechanism of V. parahaemolyticus infections has not been fully elucidated.[5] However, most clinical disease results from strains that carry either the thermostable direct hemolysin gene (tdh) or the tdh-related hemolysin gene (trh) or both genes.

[edit] Epidemiology

Outbreaks tend to be concentrated along coastal regions during the summer and early fall when higher water temperatures favor higher levels of bacteria. Seafood most often implicated includes squid, mackerel, tuna, sardines, crab, shrimp, and bivalves like oysters and clams. The incubation period of ~24 hours is followed by explosive, watery diarrhea accompanied by nausea, vomiting, abdominal cramps, and sometimes fever. Vibrio parahaemolyticus symptoms typically resolve with-in 72 hours, but can persist for up to 10 days in immunocompromised individuals. As the vast majority of cases of V. parahaemolyticus food infection are self-limiting, treatment is not typically necessary. In severe cases, fluid and electrolyte replacement is indicated.[3]

Additionally, swimming or working in affected areas can lead to infections of the eyes or ears [6] and open cuts and wounds. Following Hurricane Katrina, there were 22 vibrio wound infections 3 of which were caused by V. parahaemolyticus and 2 of these led to death.

[edit] References

  1. ^ [[1]] Center for Disease Control and Prevention, United States Department of Health and Human Services, accessed 11/30/07.
  2. ^ Ibid.
  3. ^ a b Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology, 4th ed., McGraw Hill. ISBN 0-8385-8529-9. 
  4. ^ Finkelstein RA (1996). Cholera, Vibrio cholerae O1 and O139, and Other Pathogenic Vibrios. In: Barron's Medical Microbiology (Barron S et al, eds.), 4th ed., Univ of Texas Medical Branch. (via NCBI Bookshelf) ISBN 0-9631172-1-1. 
  5. ^ Baffone W, Casaroli A, Campana R, Citterio B, Vittoria E, Pierfelici L, Donelli G (2005). "'In vivo' studies on the pathophysiological mechanism of Vibrio parahaemolyticus TDH(+)-induced secretion". Microb Pathog 38 (2-3): 133-7. PMID 15748815. 
  6. ^ Penland RL, Boniuk M, Wilhelmus KR (2000). "Vibrio ocular infections on the U.S. Gulf Coast". Cornea 19 (1): 26-9. doi:10.1097/00003226-200001000-00006. PMID 10632004. 

[edit] External links