Botulism

• What is Botulism
• Statistics on Botulism
• Risk Factors for Botulism
• Progression of Botulism
• Symptoms of Botulism
• Clinical Examination of Botulism
• Prognosis of Botulism
• How is Botulism Treated?
• Botulism References

What is Botulism

Botulism disease is the condition which refers to the syndrome produced by infection with the bacteria Clostridium botulinum. Clostridium botulinum is a common environmental micro-organism, and produces bacterial spores which can survive heating to 100 C. The clostridium botulinum anaerobic pathogenic micro-organism can multiply and produce a neurotoxin which inhibits nerve transmission by decreasing release of the neurotransmitter acetylcholine at nerve synapses.
Three forms of Botulism occur:
1) Wound botulism:
C. botulinum bacteria may enter the body through wounds.
2) Foodborne botulism:
The botulism bacterial can also survive in improperly canned or preserved food which then causes intoxication after ingestion of the food.
3) Infant botulism:
C. botulinum can colonise the gastrointestinal tract of young infants who ingest certain foods with subsequent production of the neurotoxin.

Statistics on Botulism

 

• Food-borne botulism, the first form of the disease to be identified, is responsible for 963 annual cases worldwide.Home-processed foods are responsible for most botulism outbreaks.
• Infant botulism occurs most commonly in those aged 1 week to 11 months, with peak susceptibility occurring at 2-4 months. Since infant botulism was identified in 1976, there have been 1134 recorded cases of infant botulism in the USA.
• From 1992, only 1-3 cases of wound botulism have been reported in the US each year.
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  Risk Factors for Botulism

  A very small amount of the botulism toxin can cause illness.
  People come in contact with this botulism toxin in one of three ways:
   

• Eating food contaminated with botulism toxin. It is the toxin produced by the botulism bacteria – not the bacteria itself – which causes botulism in humans.Foods that may be contaminated with the botulism toxin include:
• • Home-canned goods
  • Sausage
  • Meat products
  • Seafood
  • Canned vegetables

   

• An infant can swallowing botulism bacterial spores, which then colonise the bowel and produce toxin. Honey is a common source of botulism spores. Other sources include soil and dust.
• A wound becomes contaminated with C. botulinum and via the wound the toxin reaches the bloodstream and may spread to other parts of the body.
• Breastfeeding an infant can reduce risk of contracting botulism.
• IV drug use (rare occurence).
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  Progression of Botulism

  The botulism toxin binds irreversibly to the presynaptic membranes of peripheral neuromuscular and autonomic nerve junctions blocking acetylcholine release.
  The first symptoms of botulism, occurring 18-24 hours after ingestion of clostridium botulinum bactria, are nausea and diarrhoea. These are followed by cranial nerve weakness and then progressive symmetrical paralysis, leading to respiratory failure.
  Recovery of function requires regeneration of the nerve endings, which can take a considerable period of time.
  

  Prognosis of Botulism

  Prompt treatment for botulism significantly reduces the risk of death and those who survive botulism induced, acute paralysis usually make a full recovery.
  

  How is Botulism Treated?

  The treatment of Botulism is mainly supportive.
   

• The goal of botulism treatment is to establish a clear airway, and provide ventilatory support while the nerve endings regenerate. If breathing difficulty develops, intubation (a tube inserted through the mouth into the trachea to provide an airway for oxygen) and mechanical ventilation can be used.
• Intravenous fluids can be given to maintain hydration while swallowing difficulties persist and nasogastric feeding (feeding through a tube inserted in the nose) may be initiated.
• Antibiotics for botulism treatment (metronidazole or penicillin) are often given but have not been shown to be beneficial in the treatment of Botulism. Botulinum antitoxin is available in some countries however, the risk of anaphylaxis is relatively high so it should only be used in severe cases.
• Health care providers need to report cases of the botulism need to be reported to state health authorities so that contaminated food can be recalled and removed from stores.
• Prevention:
  • Do not give honey or corn syrup to infants who are younger than 1 year old.
  • Always discard bulging cans or off-smelling preserved foods.
  • Sterilize home canned foods by pressure cooking at 120 degrees Celcius for 30 minutes.
  • Don’t “TASTE TEST” precooked foods
  • Breast-feeding can help prevent infant botulism.

  Botulism References

  [1] Dunbar EM: Botulism [published erratum appears in J Infect 1990 May;20(3):273]. J Infect 1990 Jan; 20(1): 1-3.
  [2] eMEDICINE.
  [3] Harrison’s Principles of Internal Medicine 15th edition.
  [4] Hatheway CL: Botulism: the present status of the disease. Curr Top Microbiol Immunol 1995; 195: 55-75[Medline].
  [5] John Hopkins Public Health.
  [6] Kumar P, Clark M. CLINICAL MEDICINE. WB Saunders 2002.
  [7] MEDLINE Plus.