botulism

Botulism is a rare but serious neuroparalytic illness caused by botulinum neurotoxin produced by Clostridium botulinum and related species. The toxin blocks acetylcholine release at neuromuscular junctions, causing flaccid paralysis. Botulism is not an infection in the usual sense, but toxin-mediated.

There are seven toxin types (A–G). Types A, B, and E cause most human disease; F is rare. The toxin is heat-labile; canned foods can allow toxin formation if anaerobic conditions exist. C. botulinum spores are widespread in the environment and can survive in improperly processed foods.

The main clinical forms are foodborne botulism, infant botulism, and wound botulism. Foodborne presents with onset 6 hours to several days after ingesting toxin-containing food; symptoms include dizziness, dry mouth, blurred vision, dysphagia, symmetric progressive descending weakness, ptosis, and respiratory failure. Infant botulism results from intestinal colonization in infants, with constipation, poor feeding, and hypotonia. Wound botulism results from infected wounds producing toxin.

Diagnosis is clinical and supported by detection of toxin in serum, stool, or food; confirmation may use mouse bioassay or newer immunoassays. Treatment includes prompt administration of botulinum antitoxin to neutralize circulating toxin, and intensive supportive care with airway management. Antibiotics are used for wound botulism; not for primary foodborne toxin.

Prevention focuses on safe food processing, especially home canning, avoiding honey in infants under one year, and proper wound care to prevent anaerobic infection. The prognosis improves with early treatment but can be fatal without care.