Fundamental Food Microbiology, Third Edition - Fuad Fathir

IMPORTANT FACTS IN FOODBORNE DISEASES 325
The incidence of foodborne diseases of microbial origin is higher than that for all
others causes combined. In the U.S., between 1972 and 1978, among the total number
of cases reported of foodborne disease outbreaks, pathogenic microorganisms caused
94.4%, and only 1.1% and 4.3% were caused by parasites and chemicals, respectively.
Even at present, the occurrences of foodborne diseases caused by pathogenic
microorganisms far exceed those by all others combined. In recent years, foodborne
diseases of microbial origin have become the primary food safety concern among
U.S. consumers and regulatory agencies. This trend is probably true in most other
developed and developing countries. 1
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III. EPIDEMIOLOGICAL ASPECTS
A. Investigation of a Foodborne Disease
In general, various regulatory agencies at the local, state, and national levels are
empowered with the responsibility of investigating the cause of a reported foodborne
disease (see Appendix C). In the U.S., the regulatory agencies involved in the
investigation of a foodborne disease are the local health department; state health,
food, and agriculture departments; the federal Food and Drug Administration (FDA);
U.S. Department of Agriculture (USDA); Centers for Disease Control and Prevention
(CDC); and several others. Initially, a medical doctor who suspects a patient to have
a foodborne disease informs the local or state health officials about the incident.
These agencies, following a preliminary investigation and recognizing the cause to
be of food origin, report the incident to the appropriate federal agencies, which then
conduct an epidemiological investigation. The investigation at the state and federal
levels involves examination of the suspected foods, environmental samples, and
materials obtained from the patients for pathogens, microbial and nonmicrobial
toxins, and chemicals. Results of these tests provide direct evidence of the association
of an agent (e.g., pathogen, toxin, parasite, chemicals) with the disease. In addition
to testing suspected samples, both the sick and other people who consumed the same
food from the same source are interviewed to establish an indirect association of
the most likely foods with the disease. This information is collected, recorded, and
reported by the CDC, Atlanta, GA. (See Section IV of this chapter.)
B. Foodborne Disease Outbreak
In the U.S., the federal regulatory agencies define a foodborne disease as an outbreak
when two or more people become sick with a similar illness (symptoms) from the
consumption of the same food from the same source, and the epidemiological
investigations implicate, either directly or indirectly, the same food from the same
source as the cause of the illness. However, in the case of botulism, because of a
high fatality rate, even when only one person has the illness, it is considered an
outbreak. For chemical poisoning too, even a single case is considered an outbreak.