Fundamental Food Microbiology, Third Edition - Fuad Fathir

334 FUNDAMENTAL FOOD MICROBIOLOGY
occur more frequently. A high temperature during the summer can stimulate rapid
growth of the contaminating pathogens to reach a high level, even from a low initial
level, within a relatively shorter period. During the winter months, the growth rate
can be greatly reduced.
L. Influence of Location on Foodborne Diseases of Pathogenic
Bacterial and Viral Origin
In general, the incidence of foodborne disease outbreaks is lower in the developed
countries than in the developing countries. Several socioeconomic reasons
and climatic conditions cause this difference. However, the frequency of outbreaks
can vary greatly among regions, both in the developed and developing
countries. In the U.S., foodborne disease outbreaks have been recorded more
frequently in some states than in others. States with high populations, large
numbers of industries, and warm climates have more incidents. States in this
group are New York, Washington, California, Hawaii, and Pennsylvania (Table
23.9). Some other factors, such as a large ethnic population, greater frequency
of migration and traveling of people, as well as better surveillance systems, can
also cause a high incidence rate. In comparison, states with lower populations
had very few incidents.
M. Human Factors in Foodborne Disease Symptoms
When a group of people consumes food contaminated with live cells of pathogens
or their toxins, all the members might not develop disease symptoms. 1,2 Among
those who develop symptoms, all might not show either the same symptoms or the
same severity of a symptom. This is probably due to the difference in resistance
among individuals. One of the factors involved in developing symptoms from the
consumption of a contaminated food is susceptibility of an individual to the contaminants.
In general, infants and old, sick, and immunodeficient people are more
susceptible than normal adults and healthy individuals. The chance of developing
disease symptoms is directly related to the amount of a contaminated food consumed.
This is related to the number of viable cells of a pathogen or the amount of a toxin
consumed by an individual. The virulence of a pathogen or a toxin consumed through
a food also determines the onset of a disease and severity of symptoms. For some
Table 23.9 Influence of Location on Confirmed Foodborne Disease Outbreaks from
Pathogenic Bacteria and Viruses from 1983 to 1987 in the U.S.
High Incidence Low Incidence
State Total Range State Total Range
New York a 744 129 to 174 Wyoming 2 0 to 1
Washington 243 38 to 55 Montana 3 0 to 2
California 166 30 to 38 S. Dakota 4 0 to 2
Hawaii 138 20 to 36 Nevada 1 0 to 1
Pennsylvania 96 15 to 24 Utah 6 0 to 1
a New York City had 216 outbreaks with a range of 24 to 80 during the same period.