Botulism
What it is: A rare illness caused by the bacterium Clostridium botulinum, which produces botulin, a toxin that attacks the nerves and can lead to paralysis or death.
Symptoms: Double vision, difficulty swallowing, slurred speech, and muscle weakness, which generally begin within 18 to 36 hours, but can start as early as six hours or as late as 10 days.
Sources: Improperly canned foods; garlic or herbs packed in oil; vacuum-packaged and tightly wrapped food; luncheon meats, ham, sausage, and smoked and salted fish; and honey.
Prevention Tip: Avoid bulging or dented cans; follow hygienic canning methods and boil home-canned foods for at least 10 minutes.

Listeriosis
What it is: Listeria monocytogenes, a bacterium found in water and soil, and often carried by animals. An estimated 2,500 Americans become seriously ill from it each year, and 500 die. Pregnant women account for about one-third of all cases, which can lead to miscarriage or stillbirth, premature delivery, or infection or death of the newborn.
Symptoms: Flu-like fever and muscle aches usually appear within 48 to 72 hours but can surface after seven to 30 days. If the infection spreads to the nervous system, a sufferer may experience a stiff neck, headache, nausea, and vomiting.
Sources: Soft cheeses; unpasteurized dairy products; raw or undercooked meat, hot dogs, poultry, and fish; deli meats; fermented and dry sausage; refrigerated meat spreads; and smoked seafood.

Perfringens
What it is: The Clostridium perfringens bacteria cause a common intestinal infection that sickens about 10,000 people annually in the United States. Cafeterias and nursing homes, where large quantities of food are prepared several hours before serving, are common sources.
Symptoms: Abdominal pain, diarrhea, sometimes with nausea and vomiting, within eight to 15 hours and lasting only a day or less; these symptoms can be more serious in older or debilitated people.
Sources: Cooked foods--most often meats, meat products, gravies, and stuffings--that have been left out to cool at room temperature, allowing bacteria to proliferate.

Scombroid
What it is: A common form of fish poisoning, from histamines released by Scombrotoxin bacteria that feed on unrefrigerated fish.
Symptoms: Rash, diarrhea, flushing, sweating, headache, vomiting, abdominal pain, burning or swelling of the mouth, or a peppery taste that can appear within two minutes to two hours of eating tainted food and last a few hours. Symptoms may be more severe in patients taking the antibiotics isoniazide and doxycycline, which slow the breakdown of histamines in the liver.
Sources: Unrefrigerated fish --most often tuna, mackerel, and mahi-mahi.
Prevention Tip: Cooking, canning, or freezing will not kill the toxin, so buy only fresh, well-chilled fish, and refrigerate immediately.

Shigellosis
What it is: The Shigella bacteria, present in human feces, can wind up in the food supply through fecal contamination of water or when food is prepared and handled by workers who have not properly washed their hands after using the bathroom. There are about 448,240 cases each year.
Symptoms: Abdominal cramps, diarrhea, fever, and sometimes vomiting; blood, pus, or mucus in stools that manifests within one to seven days.
Sources: Foods requiring preparation and handling, particularly salads.

Staphyloenterotoxicosis
What it is: The common bacterium Staphylococcus aureus produces seven different toxins frequently responsible for food poisoning, though the exact number of yearly cases is unknown.
Symptoms: Diarrhea, vomiting, nausea, and abdominal pain and cramps occur within 30 minutes to eight hours, and last 24 to 48 hours.
Sources: Foods that require preparation and handling, and then are not cooked or are kept at room temperature--particularly tuna, potato and macaroni salads, and cream-filled baked goods; meats, ham, poultry, and egg products.

Toxoplasmosis
What it is: An infection caused by the Toxoplasma gondii parasite in people with weak immune systems (although more than 60 million people in the United States may be carrying the parasite, most have immune systems healthy enough to prevent it from causing illness).
Symptoms: Swollen lymph glands, muscle aches and pains within one week to one month and last for a month or more, but can remain dormant. As the infection travels though the bloodstream of someone with a weak immune system, it can damage the brain, eyes, and other organs. A small percentage of infected newborns have serious eye or brain damage at birth.
Sources: Raw or undercooked meats (especially pork, lamb, or wild game); untreated water (in rivers or ponds); parasite-infected cats.
Prevention Tip: If you are pregnant or have a weakened immune system, wear clean latex gloves while handling raw meats or gardening where cats may have used soil for a litter box.

Vibrio vulnificus infection
What it is: Vibrio vulnificus, a bacterium common in warm seawater. It's responsible for an average of 85 hospitalizations and 35 deaths each year; about half the infections strike in the Gulf Coast.
Sources: Raw or undercooked oysters, mussels, and clams.
Symptoms: Diarrhea and stomach pain within four hours or four days that will last about 2

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