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Pathogens
Bacteria – single celled, living organisms
Found almost everywhere
Cannot be seen, smelled, or tasted
Some produce toxins
*Most important prevention measure: controlling time and
temperature*
1. Bacillus cereus – cooked rice dishes
2. Listeria monocytogenes – raw meat, ready-to-eat food
such as hotdogs, deli meat, soft cheeses
*grows in cool moist environments
** can cause miscarriages
***ready-to-eat food – food that can be eaten without
further preparation, washing, or cooking, ex.: cooked food,
washed fruits and vegetables, deli meats, bakery items,
spices
3. E. coli – ground beef, contaminated produce
*found in the intestines of cattle
*takes only a small amt. to make a person sick
4. Campylobacter jejuni – poultry, water, stews and gravies
5. Clostridium perfringens – dirt, intestines of animals and
humans; meat, poultry, stews and gravies
6. Clostridium botulinum – (botulism) incorrectly canned
food, ROP food ex.: vacuum packed, juices boxes, bagged
salads etc., baked potatoes
7. Salmonella spp. – poultry, eggs, dairy products, produce
**eating only a small amt. can make a person sick
8. Salmonella Typhi – lives only in humans, linked to readyto-eat foods, beverages
9. Shigella spp. – food easily contaminated by hands (potato,
tuna, macaroni, chicken salads), contaminated water;
control flies, practice good personal hygiene
10.
Staphylococcus aureus – found in humans; *cooking
does not destroy these toxins; linked to salads, deli meat;
prevention: washing hands, practicing good personal
hygiene
11.
Vibrio – linked to oysters from contaminated water;
prevention: purchase from reputable suppliers, cook to
minimum internal temperature
Viruses (highly contagious)
 Smallest of the contaminates
 Carried by humans and animals
 Require a living host to grow
Sources: food, water, contaminated surfaces
Transferred: person to person, people to food, people to
surfaces
Prevention: NOT destroyed by cooking temperatures; wash
hands, avoid bare-hand contact with food (wear gloves),
prohibit food handlers who are sick from working
Major Viruses
1. Norovirus
2. Hepatitis A
Both are linked to ready-to-eat foods and shellfish from
contaminated water.
Parasites
 Not as common
 Cannot grow in food, have to have a living host
 Commonly associated with seafood, wild game, and
produce processed with contaminated water
 Prevention: purchase food from reputable suppliers; cook
to required minimum temperatures; if fish is to be served
raw or undercooked, make sure it has been frozen
correctly by the manufacturer.
1. Anisakis simplex – tingling in the throat, coughing up
worms; linked to raw or undercooked fish
2. Cryptosporidium parvum – linked to contaminated water
and produce; day care and medical communities have
been frequent sites of an outbreak
3. Giardia duodenalis – linked to incorrectly treated water
and produce; prevention: purchase from reputable
suppliers and wash hands
4. Cyclospora cayetanensis – linked to incorrectly treated
water and produce; prevention: purchase from reputable
suppliers and wash hands
Fungi (only sometimes make people sick, mostly they spoil
food)
1. Mold – some produce toxins; grow under almost any
condition; cooler and freezer temperatures slow the
growth but they do not kill them.
2. Yeast – can spoil food quickly; signs of spoilage include a
smell or taste of alcohol, white or pink discoloration,
bubbles, or slime.
Biological Toxins
1. Seafood toxins – cannot be smelled or tasted; cannot be
destroyed by freezing or cooking once they form in food.
Prevention: purchase from a reputable supplier
 Histamine – can be found in tuna and other fish
 Ciguatoxin – can cause reversal of hot and cold
sensations; symptoms may last months or years
 Saxitoxin – found in shellfish
 Brevetoxin – found in shellfish
 Domoic acid – found in shellfish
2. Mushroom toxins – almost always caused by eating toxic
wild mushrooms
3. Plant toxins – found in toxic plants mistaken for the
edible version; honey; undercooked kidney beans