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Botulism neurotoxins (A-F) could be transmitted by aerosol or contamination of food and water supplies.

Botulism is not transmitted from person to person.


  • Incubation period is 12-36 hours (can be several days)
  • Early symptoms include blurred vision, diplopia, and dry mouth
  • Later symptoms include dysarthria, dysphagia, dysphonia, ptosis and the development of a symmetrical, descending progressive paralysis and respiratory failure
  • Patients are usually alert and afebrile

Laboratory Diagnosis:

  • Diagnosis is primarily based on a compatible clinical presentation
  • Spinal protein is normal and characteristic findings are seen on EMG (facilitation of the compound muscle action potential on repetitive nerve stimulation)
  • Toxin can be detected in serum (collect 30 cc in red top) and stool (foodborne botulism) by mouse neutralization bioassay performed at California Microbial Diseases Laboratory

Patient Isolation:

Standard precautions. Patients do not require isolation rooms.


  • Supportive care is the mainstay of therapy; prolonged ventilatory support is often required in severe cases
  • Botulism anti-toxin (for A, B and E toxins) is in limited supply and is available only from the Division of Communicable Disease Control, California Dept of Health Services


Currently, there is no available post-exposure prophylaxis.

Thanks to Santa Clara County for information provided on this page.

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