Incubation Periods and Symptoms

      

Common   Pathogens

Incubation PeriodS

Common                          Symptoms

   Bacillus Cereus

 

1-6 hrs (vomiting)               6-24 hrs (diarrhea)

Nausea and diarrhea. Typically resolves within 24 to 48 hours

   Campylobacter

 

     

2 to 7 days               (usually 3 to 5 days)

Diarrhea (often bloody), abdominal cramps, nausea and headaches. Typically resolves within 1 to 10 days

   C. Botulinum

 

 

12 to 72 hrs                 (usually 18 to 36 hrs)

Nausea, vomiting, diarrhea, fatigue, headache, dry mouth, double vision, muscle paralysis, respiratory failure. Duration is variable (days to months).

   C. Perfringins

 

 

8 to 22 hrs            (average is 12 hrs)

Diarrhea, abdominal cramps and vomiting; usually no fever. Typically resolves within 1 to 2 days.

   E. coli O157:H7

 

 

24+ hrs to 10 days (usually 3 to 4 days)

Diarrhea (often bloody), abdominal cramps and vomiting; usually no fever. HUS may develop in rare cases. Typically resolves within 1 to 8 days (in non-complicated cases)

   Hepatitis A

 

15 to 50 days        (average is 28 days)

Diarrhea, dark urine, jaundice and flu-like symptoms, including headaches, fever, nausea and abdominal pain. Duration is variable (ranging a few weeks to 3 months).

   Listeria

 

9-48 hrs                         (for GI symptoms)

2 to 6 weeks                 (for invasive disease)

 

Fever, muscle aches, nausea, diarrhea; pregnant women may suffer flu-like symptoms and stillbirth; elderly, immune-compromised and infants can develop sepsis and meningitis. Duration is variable.

   Norovirus

 

 

12 to 72 hrs            (usually 24 to 48 hrs)

Diarrhea, abdominal cramps, vomiting, headaches and fever. Typically resolves within 1 to 3 days.

   Salmonella

 

6 to 72 hrs              (usually 12-36 hrs)

Diarrhea, abdominal cramps, nausea, vomiting and fever. Typically resolves within 4 to 7 days.

   Shigella

 

 

24 to 72 hrs             (usually 36 to 48 hrs)

Watery diarrhea, nausea, vomiting, abdominal cramps, chills and fever. Stool may contain blood and mucus. Typically resolves within 4 to 7days.

  Staphylococcus

 

30 minutes to 8 hrs (usually 2 to 4 hrs)

Diarrhea, abdominal cramps, nausea and vomiting. Typically resolves in 24 to 48 hrs.

 

Staphylococcus Fact Sheet

Staphylococcus aureus is a spherical bacterium (coccus) which typically appears in pairs, short chains, or bunched, grape-like clusters. These organisms are Gram-positive. The bacteria is capable of producing a heat-stable protein toxin that can cause illness.

Staphylococci can exist in air, dust, sewage, water, and food or on food equipment, environmental surfaces, humans, and animals. Humans and animals are the primary reservoirs. Staphylococci are present in the nasal passages and throats and on the hair and skin of 50 percent or more of healthy individuals. This incidence is even higher for those who associate with, or who come in contact with, sick individuals and hospital environments.  Although food handlers are usually the main source of food contamination in food poisoning outbreaks, equipment and environmental surfaces can also be sources of contamination with staphylococcus.

Notably, foods that require considerable preparation (using hands), and are maintained at slightly elevated temperatures, are frequently associated with outbreaks.  These foods typically include salads products (such as egg, tuna, chicken, potato, and macaroni) and bakery products (such as cream-filled pastries and cream pies).  Other foods associated with outbreaks have included sandwich fillings, dairy products, meat products, poultry and egg products.

If Staphylococci are introduced into food, the bacteria can multiply and develop pre-formed enterotoxins.  This usually occurs if the food is not kept hot enough (140°F or above) or cold enough (45°F or below).  Once ingested, illness can be caused by the preformed enterotoxins.  A toxin dose of less than 1.0 microgram in contaminated food, which is reached when the bacterial population exceeds 100,000 per gram, can produce symptoms.

The onset of symptoms in staphylococcal food poisoning is usually rapid and in many cases acute, depending on individual susceptibility to the toxin, the amount of contaminated food eaten, the amount of toxin in the food ingested, and the general health of the individual. The most common symptoms include nausea, vomiting, abdominal cramping and prostration. Some individuals may not always demonstrate all the symptoms associated with the illness. In more severe cases, headache, muscle cramping, and transient changes in blood pressure and pulse rate may occur.  Recovery generally takes only two days.

As is true with most other common food-borne pathogens, the spread of Staphylococci to foods can be prevented by following good hygienic practices.

References:

www.foodsafety.gov/~mow/chap3.html

www.cdc.gov/ncidod/dhqp/ar_MRSA_ca_public.html

www.mayoclinic.com/health/mrsa/DS00735

Staphylococcus Images