Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.
Food poisoning is an illness caused by eating or drinking food or water
contaminated with viruses, bacteria, toxins, parasites, or chemicals.
Food Poisoning vs Gastroenteritis (Stomach Flu)
flu) is defined as an infection or irritation of the
gastrointestinal tract, especially the stomach or intestines. It is a slightly
more specific term that can describe a type of food poisoning; however, the term
is used most often to describe stomach irritation or inflammation and is used to
describe non-food-related stomach irritations.
Viruses are the most frequent cause of food poisoning in the U.S. The next
highest causes are bacteria. About 31 viral and bacterial pathogens are
responsible for almost 9.4 million diagnosed food poisoning illnesses per year;
about 39 million food poisoning cases are unspecified (undiagnosed). Yearly,
about 128,000 people are hospitalized and about 3,000 die from all causes of
The most common pathogens that cause food poisoning and the approximate
number of people with food poisoning are:
Infectious agents comprise the largest category of food poisoning, but as
seen from the above top categories, viral infections comprise the bulk of
infected patients but are far less likely to cause hospitalizations and deaths
than Salmonella bacteria. Because the bulk of "unspecified" causes is probably
similar to the makeup of the diagnosed causes, this grouping of viruses and
bacteria is considered to be the main causes of food poisoning in the U.S.
There are many toxins that can cause food poisoning. Some are produced by
bacteria on or in food and others are produced by plants and animals/fish or
other organisms that are ingested. There are many plants and animals/fish that
can be poisonous under certain conditions but they are encountered infrequently
or under special conditions.
Some general toxin types, various toxins and their sources:
Certain chemicals are considered toxins that can cause
food poisoning. Although there are over 80,000 chemicals used in the U.S., only
a few have been well studied. While most do not enter into foods, some do and
cause food poisoning. An example of such a chemical is
mercury, found in
drinking water and in fish such as tuna and marlin. Other examples of chemicals
that can be toxic if enough contaminates food and water are pesticides,
polychlorinated biphenyls, and lead.
The causes of food and water poisoning are
numerous. This brief listing of causes should suffice as a framework to begin
more detailed studies of food poisoning.
The symptoms of Salmonella infections depend on the overall health of the infected person (for example, normal or with a suppressed immune system) and the particular serovar infecting the patient. Symptoms usually begin about 12-72 hours after ingestion of the bacteria. In general, people contract S. spp (for example, serovars S. enteritidis, S. cholerasuis) that usually cause a self-limiting diarrhea, nausea, and vomiting termed salmonellosis or S. gastroenteritis.