Botulism is a potentially deadly illness that is caused by a toxin produced by specific bacteria.
The bacteria are found in the soil and at the bottom of lakes, streams, and oceans. The intestinal tracts of fish, mammals, crabs, and other shellfish may contain the bacteria and its spores. Bacterial spores can survive in improperly prepared foods. A very small amount of the botulism toxin can cause illness. People are exposed to this toxin in one of three ways:
In some cases, the source of the bacteria is unknown. Botulism toxin is also a potential bioterrorism agent.
Factors that increase your chance of botulism include:
Symptoms begin in the face and eyes, and progress down both sides of the body. If left untreated, muscles in the arms, legs, and torso, as well as those used in breathing become unable to move. Death can occur.
Symptoms can range from mild to severe and include:
When food is the cause of botulism, symptoms usually start within 36 hours of eating the contaminated food. Some people notice symptoms within a few hours. Others may not develop symptoms for several days. Some people experience nausea, vomiting, and diarrhea.
When a wound is the cause of botulism, symptoms start within 4-14 days.
The doctor will ask about your symptoms and medical history. A physical exam will be done. Blood, stool, and stomach contents will be tested for the toxin. In infants, stool will also be tested. If available, samples of questionable food may also be tested for the toxin and bacteria. A wound culture will be done if wound botulism is suspected.
Your doctor may need to test other bodily fluids with lumbar puncture.
Your doctor may need to evaluate the nerves in your body. This can be done with nerve conduction tests.
The most serious complication is respiratory failure. Treatment aims to maintain adequate oxygen supply. This may require mechanical ventilation and close monitoring in an intensive care unit. IV fluids or feeding through a tube may also be necessary.
If treatment begins early, an antitoxin can stop the paralysis from progressing and may shorten symptoms. It is usually given before the disease is confirmed. It does not reverse the disease process.
High temperatures can destroy the botulism toxin. Strategies to prevent botulism include:
Centers for Disease Control and Prevention
Food Safety—US Department of Health and Human Services
Canadian Partnership for Consumer Food Safety Education
Botulism. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/botulism. Updated July 26, 2011. Accessed August 7, 2013.
Botulism. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T116075/Botulism. Updated August 4, 2015. Accessed September 29, 2016.
Botulism. Department of Health and Human Services Food Safety website. Available at: http://www.foodsafety.gov/poisoning/causes/bacteriaviruses/botulism/index.html. Accessed August 7, 2013.
Botulism. Nemours Kids Health website. Available at: http://kidshealth.org/kid/watch/house/botulism.html. Updated October 2011. Accessed August 7, 2013.
Last reviewed May 2016 by David Horn, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.