Botulism
Definition
Botulism is a potentially deadly illness that is caused by a toxin produced by a bacterium called Clostridium botulinum . This bacterium 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 C botulinum and its spores. The bacterium's spores can survive in improperly prepared foods.
Causes
A very small amount of the botulism toxin can cause illness. People come in contact with this toxin in one of three ways:
-
Food can be contaminated with the bacteria and its toxin. It is the toxin produced by
C. botulinum
—not
C botulinum
itself—that causes botulism in humans. Food that may be contaminated with the toxin include:
- Home-canned goods
- Sausage
- Meat products
- Seafood
- Canned vegetables
- Honey
- If an infant swallows C botulinum spores, they will grow in the baby's body and produce the toxin. Unlike adults and older children, infants become sick from toxin produced by bacteria growing in their own intestines. Honey is a prime source of infant botulism. Other sources include soil and dust.
- A wound can become infected with the bacteria (rare in the US). The toxin then travels to other parts of the body through the bloodstream.
In some cases, the source of the bacteria is unknown. Botulism toxin is also a potential bioterrorism agent.
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition.
Risk factors for botulism include:
- Eating improperly canned foods
- For infants, consuming honey
- Using IV drugs (rare)
Symptoms
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 paralyzed. Death can occur.
Symptoms can range from mild to severe and include:
In adults:
- Muscle weakness
- Dizziness
- Double or blurred vision
- Droopy eyelids
- Trouble swallowing
- Dry mouth
- Sore throat
- Slurred speech
- Difficulty breathing
- Constipation
In babies:
- Constipation
- Not eating or sucking
- Little energy
- Poor muscle tone
- Feeble cry
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 to 14 days.
Diagnosis
The doctor will ask about your symptoms and medical history, and perform a physical exam. Blood, stool, and stomach contents will be tested for the toxin. In infants, stool will also be tested for C botulinum . 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.
Tests to rule out other medical conditions may include:
- Blood tests
- MRI scan —a test that uses magnetic waves to make picture of the inside of the brain
- Spinal fluid analysis
- Nerve conduction tests
Treatment
Supportive Care
The most serious complication is respiratory failure. Treatment aims to maintain adequate oxygen supply, which may require a ventilator and close monitoring in an intensive care unit. Feeding through a tube may also be necessary.
Intubation to Assist with Breathing
Antitoxin
If treatment begins early, an antitoxin can stop the paralysis from progressing and may shorten symptoms. It does not reverse the disease process.
Methods to Eliminate the Toxin
Methods to eliminate the toxin include:
- Enemas
- Suctioning of stomach contents
- Medication to stimulate vomiting
- Surgery to clean a wound
- Antibiotics to treat a wound infection
Prevention
High temperatures can destroy the botulism toxin. Strategies to prevent botulism include:
- Do not feed honey to children less than one year old.
- Refrigerate oils that contain garlic or herbs.
- Bake potatoes without foil. If potatoes are wrapped in foil, keep them hot until served or refrigerate them.
- Do not taste foods that appear spoiled.
- Do not eat food from a can that is bulging.
- Boil home-canned foods for 10 to 20 minutes before eating.
- Practice good hygiene when canning. Follow government recommendations.
- Seek medical care for wounds. Return to the doctor if a wound looks infected (redness, warmth, pus, tenderness).
- Do not inject illicit drugs.
RESOURCES:
Centers for Disease Control and Prevention
http://www.cdc.gov/
Center for Food Safety and Applied Nutrition
http://www.cfsan.fda.gov/
CANADIAN RESOURCES:
Canadian Partnership for Consumer Food Safety Education
http://www.canfightbac.org/en/
Health Canada
http://www.hc-sc.gc.ca/index-eng.php/
References:
AAP 2000 Red Book: Report of the Committee on Infectious Diseases . 25th ed. American Academy of Pediatrics; 2000.
Cecil Textbook of Medicine . 21st ed. WB Saunders Company; 2000.
Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov .
Nelson Textbook of Pediatrics . 16th ed. WB Saunders Company; 2000.
Principles and Practice of Infectious Diseases . 5th ed. Churchill Livingstone, Inc; 2000.
Last reviewed November 2008 by David L. Horn, MD, FACP
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.
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