Incubation Period Duration of Illness Predominant Symptoms Foods Commonly Implicated
Campylobacter jejuni 3-5 days 2-5 days
occ. >10 days
Sudden onset of diarrhrea, abdominal pain, nausea, vomiting Raw or undercooked poultry, raw milk, meat, untreated water
Escherichia coli

12-72 hrs (enterotoxigenic)
longer in others
3-14 days Severe colic,
watery to profuse diarrhea,
sometimes bloody
(also see Haemolytic Uraemic Syndrome)

Many raw foods, unpasteurized milk, contaminated water, minced beef
Salmonella serovars 6-72 hrs 3-5 days Abdominal pain, diarrhea, chills, fever, malaise Meat, chicken, eggs and egg products
Salmonella typhi/paratyphi Typhoid:
1-3 wks Paratyphoid:
1-10 days

(chronic carriers occur)
Sustained fever, headache constipation rather than diarrhea - systemic illness Raw or undercooked poultry, raw milk, meat, untreated water
Shigella spp. 12-96 hrs 4-7 days Malaise, fever, vomiting, diarrhea (blood & mucus) Any contaminated food or water
Yersinia enterocolitica 3-7 days 1-21 days Acute diarrhea, sometimes bloody, fever, vomiting Raw meat and poultry, milk and milk products
Vibrio cholerae few hours
to 5 days
3-4 days Asymptomatic to profuse dehydrating diarrhea Raw seafood, contaminated water
Vibrio parahaemolyticus 12-24 hrs 1-7 days Abdominal pain,
diarrhea/vomiting of moderate severity
Raw and cooked fish, shellfish, other seafoods
Listeria monocytogenes 1-90 days days Gastrointestinal symptoms rare; flu-like symptoms to meningitis/septicaemia; infection in pregnancy can result in abortions, neonatal infection Unpasteurized milk, soft cheese, pâté, coleslaw
Norwalk and other SRSV 24-48 hrs 12-48 hrs Severe vomiting, diarrhea Oysters, clams, other food contaminated by human excreta
Rotaviruses 24-72 hrs 3-7 days Malaise, headache, fever, vomiting, diarrhea Contaminated water
Hepatitis A 15-50 days usually
1-2 weeks
Fever, nausea, abdominal discomfort, possibly jaundice Contaminated water, shellfish, salads
Cryptosporidium 1-12 days 4-21 days Profuse watery diarrhea Contaminated water and food
Giardia lamblia 1-3 weeks 1-2 weeks
to months
Loose pale greasy stools,
abdominal pain
Contaminated water, food contaminated by infected food handlers
Entomoeba histolytica 2-4 weeks weeks-months Colic, mucous or bloody diarrhea Contaminated water and food
Toxin Producing Bacteria
Bacillus cereus
(toxin in food)
1-6 hrs < 24 hrs Nausea, vomiting, diarrhea, cramps Cereals, rice, meat products, soups, vegetables
Clostridium botulinum 12-36 hrs Variable (Neurotoxin) hence blurred or double vision, difficulty swallowing, respiratory paralysis Canned food, often home canned food
(low acid)
Clostridium perfringens
(toxin in gut)
8-20 hrs 24 hrs Sudden onset colic,
Meats poultry, stews, gravies, (often reheated)
Staphylococcus aureus
(toxin in food)
30 min-8 hrs 24 hrs Acute vomiting, purging, may lead to collapse Cold foods (much handled during preparation), milk products, salted meats