Fundamental Food Microbiology, Third Edition - Fuad Fathir

382 FUNDAMENTAL FOOD MICROBIOLOGY
including fish, oysters, crabs, shrimp, and lobster. In unrefrigerated raw and cooked
seafoods, Vib. parahaemolyticus can grow rapidly, especially at 20 to 30�C. In
temperature-abused seafoods, cells can reach an infective dose level very rapidly,
even from a low initial population. Many outbreaks in the U.S. were identified to
be due to inadequate cooking and cross-contamination of cooked seafoods, followed
by improper holding temperatures. 33–35
7. Prevention
Several factors need to be considered in controlling gastroenteritis from Vib. parahaemolyticus.
The seafoods harvested from an estuary should be assumed to contain
Vib. parahaemolyticus, some strains of which can be pathogenic. In unrefrigerated
raw, improperly heated, or postheat-contaminated seafood, the cells can multiply
rapidly. Once the pathogenic strains grow to infective numbers, even heat treatment
cannot destroy the toxin. With this understanding, the control methods should include
the following: no consumption of raw seafoods, proper heat treatment of seafoods,
proper sanitation to avoid cross-contamination of heated foods, proper refrigeration
of raw and heated products, and consumption of the food within a reasonable period
of time. Temperature abuse, even for a short duration, of a seafood should be
avoided. 33–35
B. Vibrio vulnificus Septicemia
Vib. vulnificus is a lactose-positive, salicin-positive Vibrio species found in the estuarine
environment in the coastal waters. It is considered a highly lethal pathogen because
of its ability to invade the bloodstream. Vib. vulnificus has been associated with
fulminating septicemia from the consumption of contaminated seafood, as well as a
progressive cellulitis resulting from wound infection. Following consumption of contaminated
seafood, in many cases raw oysters, the cells penetrate the intestinal wall
and produce primary septicemia in 20 to 40 h. Symptoms are chills, fever, and prostration,
with occasional vomiting and diarrhea. The fulminating septicemia sets up
rapidly, which can be fatal in many cases. The infection and fatality rate is very high
(40 to 60%) among people with liver and gastric diseases and immunodeficiencies.
Control measures should include methods discussed for Vib. parahaemolyticus. Susceptible
individuals should avoid consumption of raw seafoods, such as oysters. 33,34,36
A. Importance
IX. ENTERIC VIRUSES
Enteric viruses have the potential of becoming a major cause of foodborne illness
in the U.S. and most other countries. However, unlike bacterial pathogens, they are
difficult to detect and recover from a contaminated food; for some viruses, suitable
methods to isolate from a food have not been developed and for some other viruses
very little research has been conducted to develop methods to detect them in foods.