Incubation Period

Although incubation periods—the time between ingestion of a foodborne pathogen and the onset of symptoms—are only ranges, and wide ones at that, they can still be used to identify a suspect food poisoning claim.  For example, the claimant who insists that an E. coli O157:H7 illness was sparked by the hamburger eaten an hour before the onset of illness does not have a viable case. The incubation period of E. coli O157:H7 is one to ten days, typically two to five days.

Incubation Periods of Common Foodborne Pathogens

Staphylococcus aureus 1 to 8 hours, typically 2 to 4 hours.
Campylobacter 2 to 7 days, typically 3 to 5 days.
E. coli O157:H7 1 to 10 days, typically 2 to 5 days.
Salmonella 6 to 72 hours, typically 18-36 hours.
Shigella 12 hours to 7 days, typically 1-3 days.
Hepatitis A 15 to 50 days, typically 25-30 days.
Listeria 3 to 70 days, typically 21 days.
Norovirus 24 to 72 hours, typically 36 hours.

So, if you suffer from a foodborne illness, it is not usually the last meal you ate.  Also, a stool culture for the above – except Listeria and Hepatitis A – which need blood tests – is the best way to definitively determine what “bug” has made you ill.

If you test positive in either stool or blood for one of the above bacteria or viruses, the doctor, lab or hospital is required to alert the local and state health departments, and they are obligated to interview you about the possible source of your illness.