Food Biochemistry and Food Processing

698 Part VII: Food Safety

commonly implicated in food and waterborne ill-
ness is Girdia.Outbreaks of food and waterborne ill-
ness have been reported in the United States and the
United Kingdom (Craun 1990, Porter et al. 1990).
Infection with this parasite is associated with unsan-
itary conditions, and contaminated water is the most
common source of infection.

FOODBORNEFUNGI

Fungi most commonly associated with foodborne
intoxications are Penicillium, Aspergillus,and Fus-
arium. The types of foods that may contain myco-
toxin contamination are listed in Table 30.3. A food-
borne fungi outbreak associated with consumption
of corn contaminated with Aspergillus flavuswas
reported in India. The outbreak involved 1000 cases
and 100 deaths (Krishnamachari et al. 1975). Mold
growth can occur in foods stored under high temper-
ature or humidity, resulting in the production of
mycotoxin, which can be harmful to humans.

FOODBORNEVIRUSINFECTION

Viruses from human fecal origin can result in illness
if ingested with food or water. Food or waterborne
viruses commonly associated with human illness are
listed in Table 30.3. Viral gastroenteritis is caused by
Norwalk-like viruses and in some cases by the cali-
civirus and astrovirus groups. The symptoms often
include acute but short self-limiting episode of diar-

rhea and vomiting. The viruses can be transmitted

from person to person via contaminated utensils and

foods. Foodborne viral hepatitis in humans is caused

by the hepatitis A or hepatitis E virus. The onset of

hepatitis may be preceded by anorexia, fever, fa-

tigue, nausea, and vomiting. Infected individuals shed

the organism in feces, which if allowed to contami-

nate food or water, can result in person-to-person

transmission (Caul 2000).

EMERGING PATHOGENS AND

FOOD SAFETY

Emerging infectious diseases have increased in the

last two decades and are likely to increase in the fu-

ture. Hence, the characteristics of the etiologic agents

of these diseases must be considered when design-

ing control measures to ensure food safety. There

are two types of emergence: true emergence and

reemergence. A true emergence involves the occur-

rence of microbial agent not previously identified as

a public health threat. A reemergence involves the

occurrence of a microbial agent causing disease in a

new way not previously reported or the reemergence

of a human disease after a decline in incidence.

Emergence may be due to the introduction of a new

agent, to recognition of an existing disease that was

not previously detected, or to environmental pres-

sures resulting in occurrence of a pathogen that can

cause human disease. For example the occurrence of

Table 30.3.Foodborne Parasites, Fungi, and Viruses Associated with Food- or Waterborne
Illness

Pathogen Sources of Pathogen or Toxin

Parasites
Cryptosporidium Contaminated surface water or foods in contact with contaminated
water
Cyclospora Raspberry, mesculun lettuce, and basil
Sarcocystis Raw or undercooked meat
Toxoplasma Raw or undercooked meat
Giardia Contaminated surface water
Fungi
Penicillium Mycotoxins in apple juice, walnuts, corn and cereals
Aspergillus Mycotoxins in groundnuts, corn, figs and tree nuts
Fusarium Mycotoxins in cereals, corn, wheat and barley
Viruses
Hepatitis A and E Contaminated water, fruits and vegetables, raw shellfish, raw oysters
Norwalk/Norwalk–like viruses Variety of foods and water
Calcivirus Water and contaminated foods
Astrovirus Water and contaminated foods