insects may also contaminate foods with shigella bacteria. Outbreaks of shigellosis in a
food service facility indicate a breakdown in personal hygiene and food protection.
Strict hand-washing, personal cleanliness, and waste burial are the best protection from
shigellosis. In addition, insects and rodents should be controlled as much as possible.
Symptoms consist of diarrhea and cramps, accompanied by fever and vomiting. They
usually develop 2 to 3 days after consuming the food containing the bacteria.
FOODBORNE INFECTIONS CAUSED BY VlRUSES
a. At one time, viruses were not regarded as being a cause of foodborne
disease. Now it is known that this is not true. Infectious hepatitis is a serious foodborne
disease caused by a virus. Infectious hepatitis may occur after eating shellfish,
especially raw oysters and clams; the shellfish are taken from water contaminated by
sewage and human fecal matter. Symptoms of hepatitis include extreme fatigue,
nausea, fever, and abdominal discomfort. In addition, some people develop jaundice (a
yellowish coloring of the skin).
b. Foods such as milk and potato salad may contain other viruses causing
foodborne diseases. In these cases, a person who has had the disease or
contaminated water is usually the source of the virus. Cooking shellfish, pasteurizing
milk, using safe water supplies, and practicing safe food handling techniques will control
these viral infections.
FOODBORNE INFECTIONS CAUSED BY PARASITES
a. Outbreaks of foodborne infections due to parasites are not common in the
United States. However, persons returning from foreign countries may bring parasites
with them. There are many diseases caused by parasites. This lesson will discuss
amoebiasis (amoebic dysentery), a common parasitic disease that may concern a
preventive medicine specialist.
b. Amoebiasis occurs when moist, high protein foods, such as meat, eggs,
poultry, milk, and milk products, are contaminated with human feces from infected
persons. Water contaminated with sewage is also frequently involved. The major
symptom of amoebic dysentery is diarrhea of varying severity. The symptoms will
usually develop within a few days but may take several weeks or months to appear.
Occasionally, amoebic dysentery is a fatal disease.
Section III. FOODBORNE INTOXICATIONS
a. Foodborne intoxication occurs when certain microorganisms grow in foods
and produce chemicals that are toxic (poisonous) to the person eating the food. In