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Chapter 28
Microbial Hazards in Foods: Food - Borne
Infections and Intoxications
Daniel Y. C. Fung
Introduction
Food is essential for human survival. Food is
also essential for microorganisms to grow
and thrive. Therefore, for the protection of
human health and well - being, it is important
to understand the microbial hazards in foods.
All through history, human beings were no
doubt affected by a great variety of food -
borne diseases through their consumption of
water and food.
No one knows for certain the number of
cases of food - borne intoxications and infec-
tions occurring annually in the world. There
are an estimated 76 million cases of food -
borne illnesses in the United States every
year, resulting in $5 – 17 billion in economic
and productivity losses annually. Food - borne
diseases caused more than 5,000 deaths a
year over the last 10 years. In countries with
poor sanitation, one can only surmise that the
number of food - borne disease cases is much
higher.
Efforts have been made to ensure better
food safety and to control all kinds of patho-
gens. In the United States, consumers have a
heightened awareness of the role of food -
borne diseases due to some sensational
outbreaks of food - borne diseases affecting
large numbers of people, including children
who died after consuming undercooked
hamburger, tainted cheeses, or some other
contaminated food. As a result, the U.S.
government has implemented tighter moni-
toring programs and Hazard Analysis Critical
Control Point (HACCP) procedures in the
food industry to attempt to curtail the out-
breaks and protect the safety of consumers.
Consumers are much more aware of the great
potential for large - scale food - borne out-
breaks and demand a safer food supply. At
the same time, consumers are also demand-
ing more fresh foods, minimally processed
food, and organic foods, where control of
food - borne pathogens is more diffi cult. There
is also a drastic demographic change in
society where more and more people live
longer, and yet aging also tends to weaken
the immune system, making these individu-
als more vulnerable to food - borne pathogens.
People with immunocompromising diseases
are also surviving longer, but they too are
more susceptible to food - borne disease.
Meanwhile, food distribution systems have
also been greatly improved, and thus produc-
tion of food in one location can be trans-
ported hundreds and thousands of miles in a
short time. When a problem occurs, the
amount of food involved can be astronomi-
cal, such as the case where 25 million pounds
of ground beef were recalled due to one
contamination source of Escherichia coli
O157 : H7; the company involved is no longer
in existence as a major player in food supply.
Another important development is interna-
tional trade. Vast amounts of food are regu-
larly shipped from one country to another
with minimal monitoring of the microbial
safety of the food involved. To complicate
matters further, new microorganisms are