Common Food Plant Pathogens
Bacillus Cereus
Description: A gram-positive aerobic spore former
Typical Source for Contamination: Soil and starchy foods such as rice
Products of Concern: Unrefrigirated cooked foods
Symptoms: A wide variety of foods including meats, milk, vegetables, and fish have been associated with the diarrheal type food poisoning. The vomiting-type outbreaks have generally been associated with rice products; however, other starchy foods such as potato, pasta, and cheese products have also been implicated. Food mixtures such as sauces, puddings, soups, casseroles, pastries, and salads have frequently been incriminated in food poisoning outbreaks.
Complications Possible: Severe systemic and pyogenic infections, gangrene, septic meningitis, cellulitis, panophthalmitis, lung abscesses, infant death, and endocarditis.
Susceptible Populations: All
Campylobacter Jujuni
Description: A gram-negative bacteria requiring low oxygen levels. This bacteria is the leading cause of bacterial diarrheal illness.
Typical Source for Contamination: Cattle, birds including chickens, flies and environmentally in non-chlorinated water sources.
Products of Concern: Raw chicken, unpasteurized milk.
Symptoms: Diarrhea
Complications Possible: Haemolytic uremic syndrome, internal organ infections
Susceptible Populations: All although children under 5 and young adults between 15 and 29 appear particularly susceptible.
Clostridia Botulinum
Description: A gram-positive anaerobic spore former that produces a neurotoxin. There are 4 strains that cause botulism in humans.
Typical Source for Contamination: Soil, intestinal tracts of fish and animals, shellfish
Products of Concern: improperly canned foods primarily
Symptoms: Lack of energy, weakness, dizziness, double vision, difficulty speaking, swallowing and breathing.
Complications Possible: Paralysis, death
Susceptible Populations: All
Clostridium Perfringens
Description: A gram-positive anaerobic spore former
Typical Source for Contamination: Widely distributed in the environment and may be present in the intestines of humans and animals.
Products of Concern: Meat and meat products
Symptoms: Abdominal cramps and diarrhea.
Complications: Death due to dehydration. Rarely necrotic enteritis.
Susceptible Populations: Children and the elderly.
Escherichia Coli (E Coli)
Description: There are 4 classes of E coli that cause diarrhea in humans. The strain most often of concern in food processing is O157:H7
Typical Source for Contamination: Feces of animals or humans.
Products of Concern: Ground meats, dry-cured meats, and sausages, cheese curds, vegetables, unpasteurized juices.
Symptoms: Severe cramping and diarrhea. Occasionally vomiting.
Complications: Hemolytic uremic syndrome.
Susceptible Populations: Young children and the elderly particularly for potentially fatal complications.
Listeria Monocytogenes
Description: Gram-positive bacteria widely distributed in the environment which can be present in the intestines of humans and animals. Very hardy and can survive freezing and drying. Can multiply at refrigeration temperatures.
Typical Source for Contamination: Environmental
Products of Concern: Ready to eat foods, raw and cooked meats, soft cheeses, raw vegetables.
Symptoms: For most healthy people there are no symptoms and the bacteria causes no ill effects. For the susceptible populations, listeriosis can cause nausea, septicemia, meningitis, uterine or cervical infections in pregnant women, vomiting, diarrhea.
Complications: Stillbirth, death. Mortality rates as high as 70% have been quoted.
Susceptible Populations: Pregnant women, elderly, immunocompromised individuals.
Salmonella
Description: Widespread gram-negative bacteria
Typical Source for Contamination: All animals but particularly pigs and poultry, water, soil, insects, animal feces, raw foods
Products of Concern: Raw meats, eggs, dairy products, seafood, sauces & salad dressings, powdered products, peanut butter, chocolate
Symptoms: Nausea, vomiting, diarrhea, fever, and headache. Chronic consequences are arthritic symptoms.
Complications: Typhoid and typhoid like fevers, arthritis, death.
Susceptible Populations: All but particularly infants, elderly and AIDS patients.
Shigella
Description: A gram-negative bacteria
Typical Source for Contamination: Human feces
Products of Concern: Salads, raw vegetables, milk, and dairy products, poultry.
Symptoms: Abdominal cramping and pain, diarrhea, fever, vomiting.
Complications: Hemolytic uremic syndrome, arthritis, death.
Susceptible Populations: All but particularly infants and elderly.
Staphylococcus Aureus
Description: A gram-positive bacteria
Typical Source for Contamination: Staphylococci exist in air, dust, sewage, water, milk, and food or on food equipment, environmental surfaces, humans, and animals. Humans and animals are the primary reservoirs
Products of Concern: Meat and meat products; poultry and egg products; salads such as egg, tuna, chicken, potato, and macaroni; bakery products such as cream-filled pastries, cream pies, and chocolate eclairs; sandwich fillings; and milk and dairy products. Foods that require considerable handling during preparation and that are kept at slightly elevated temperatures after preparation are frequently involved in staphylococcal food poisoning.
Symptoms: Nausea, vomiting, and cramping. In severe cases, headache and muscle cramping may occur.
Complications: Rarely, death of the elderly or infants.
Susceptible Populations: All