Fish Microbiology and Quality Assurance (2+2)

5.7. Foodborne gastroenteritis caused by Vibrio parahaemolyticus

Unit 5 - Foodborne pathogens

5.7. Foodborne gastroenteritis caused by Vibrio parahaemolyticus
Characters

• Food poisoning by V. parahaemolyticus is caused mainly by the consumption of seafoods containing live bacteria. It is an autochthonous marine bacterium associated naturally with marine organisms.
• V. parahaemolytixcus is G-ve, straight/curved rod, halophilic requiring 1~3% salt for growth, can grow at 7% NaCl, optimum temperature for growth is 35-37^oC but can grow over a range of temperature (10-44^oC), minimum temperature for growth is 7^oC, grow in a pH range of 5~11, sensitive to freezing and chilling temperature and killed by heating at 100^oC.
  
• Isolates from cases of food poisoning (about 97%) are haemolytic (Kanagawa positive), and majority of environmental isolates are non-haemolytic (Kanagawa negative).
  
• Food poisoning by this bacterium causes gastroenteritis. These are killed by heating. Following good sanitation and GMP would prevent its build up in foods. This organism is the major cause of gastroenteritis in Japan.

Symptoms of illness
Raw food of marine origin, marine fish, shellfish, crustaceans and fish products are involved in cases of food poisoning. Permissible limit in foods is 104 /g.
Symptoms of illness include abdominal cramps, diarrhea, nausea, vomiting, bloody stools, mild fever, chills and headache. Incubation period is 4-48 hrs and infected individuals recover with in 2-5 days.

Prevention of outbreak

• Cooking food thoroughly
• Chilling food rapidly
• Preventing cross contamination from marine fish
• Following sanitary measures