Foodborne Botulism

by National Institute of Health

Botulism is a rare but serious illness. Each year, U.S. health care providers report an average of 110 cases of food, infant, and wound botulism to Centers for Disease Control and Prevention (CDC). About 10 to 30 outbreaks of foodborne botulism are reported annually. Although this illness does not occur frequently, it can be fatal if not treated quickly and properly. This fact sheet will focus on botulism caused by eating contaminated food.

Botulism is caused by toxin produced by Clostridium botulinum bacteria. This toxin affects your nerves and, if untreated, can cause paralysis and respiratory failure. C. botulinum toxin is one of the most powerful toxins known in nature. Exposure to the toxin, particularly in an aerosolized (spray) form, can be fatal. C. botulinum has been made into weapons by rogue states and is a focus of current efforts to counter bioterrorism.

Transmission

Often, cases of foodborne botulism come from home-canned foods with low acid content, such as asparagus, green beans, beets, and corn. C. botulinum is anaerobic, which means it can survive and grow with little or no oxygen. Therefore, it can live very well in sealed containers. Outbreaks of the infection, however, are often from more unusual sources such as chili peppers, tomatoes, and improperly handled baked potatoes wrapped in aluminum foil.

Symptoms

• Double vision and drooping eyelids
• Slurred speech
• Dry mouth and difficulty swallowing
• Weak muscles

Symptoms of foodborne botulism usually begin within 18 to 36 hours after you eat contaminated food, but can occur in as few as 6 hours or as much as 10 days afterward.

Diagnosis

A health care provider can use laboratory tests to identify C. botulinum toxin in your blood or stool if you are infected.

Treatment

If you are diagnosed early, your health care provider can treat foodborne botulism successfully with an antitoxin that blocks the action of the bacterial toxin circulating in your blood. Although antitoxin keeps the disease from becoming worse, it will still take many weeks before you recover. Your health care provider may try to remove any contaminated food still in your gut by making you vomit or by giving you an enema.

Prevention

• Follow strict hygienic steps when home canning.
• Refrigerate oils containing garlic or herbs.
• Keep baked potatoes wrapped in aluminum foil either hot until served or refrigerated.
• Consider boiling home-canned food before eating it to kill any bacteria lurking in the food.

Complications

If left untreated, this illness can cause paralysis of the arms, legs, trunk, and the muscles that help you breathe. The paralysis usually improves slowly over several weeks. People who develop severe botulism experience breathing failure and paralysis and need to be put on ventilators (breathing machines).

About the Author

NIH is the nation's medical research agency - making important medical discoveries that improve health and save lives. The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services, is the primary Federal agency for conducting and supporting medical research.