The “Big 6” are six pathogens that are so contagious the FDA Food Code says a food handler who has one of them must be excluded or restricted from working. They show up on almost every food handler and manager exam, so memorize them.
The Big 6 pathogens
- Norovirus — spread by the fecal-oral route and vomit; extremely contagious. Linked to ready-to-eat food touched with bare hands.
- Hepatitis A — a virus that attacks the liver; can be spread before symptoms appear. Prevented by handwashing and no bare-hand contact with ready-to-eat food.
- Salmonella Typhi — causes typhoid fever; carried by humans.
- Nontyphoidal Salmonella — found in poultry, eggs, and dairy; cook to correct temperatures.
- Shigella spp. — found in feces; spread by flies and people with poor hygiene.
- Shiga toxin-producing E. coli (STEC) — including E. coli O157:H7; linked to undercooked ground beef and contaminated produce.
Why they matter for food handlers
If you are diagnosed with any of the Big 6, you must report it to your manager and stay away from food. The two best defenses are proper handwashing and avoiding bare-hand contact with ready-to-eat food.
On your exam: remember that Norovirus and Hepatitis A are the two viruses in the Big 6 and are most often linked to ready-to-eat food and poor personal hygiene.
Frequently asked questions
What are the Big 6 pathogens?
Norovirus, Hepatitis A, Salmonella Typhi, nontyphoidal Salmonella, Shigella, and Shiga toxin-producing E. coli (STEC).
Why are they called the Big 6?
Because they are highly infectious and the FDA requires food handlers diagnosed with them to be excluded or restricted from working with food.
Ready to test yourself? Take our free food handler practice test (instant answers and explanations), or review the full food handler study guide.