Bacillus cereus

Question 1

Disease

Answer 1

Food poisoning.

Question 2

Transmission

Answer 2

• Spores on grains (rice)
• survive steaming & rapid
  frying.
• germinate when rice is kept warm for many hours (reheated fried rice).
• Portal of entry= gastrointestinal tract

Question 3

Pathogenesis

Answer 3

• produces 2 enterotoxins.

(1) mode of
action same as cholera
toxin (adds adenosine diphosphate ribose=ADP-ribosylation, to a G protein,
stimulates adenylate cyclase-> increased concentration of cyclic AMP within enterocyte).

(2) resembles staphylococcal enterotoxin (superantigen).

Question 4

Clinical Findings

Answer 4

2 syndromes

(1) short incubation period (4 hours)-> nausea
& vomiting.
- similar to staphylococcal food poisoning.

(2) long incubation period (18 hours)-> watery, nonbloody diarrhea, resembling clostridial
gastroenteritis.

Question 5

Laboratory Diagnosis

Answer 5

not done

Question 6

Treatment

Answer 6

symptomatic

Question 7

Prevention

Answer 7

Rice not kept warm for long periods