Foodborne botulism

Foodborne botulism is a rare but potentially life-threatening neuroparalytic illness caused by ingestion of preformed botulinum neurotoxin (BoNT) produced by the bacterium Clostridium botulinum. The toxin is typically found in improperly preserved, canned, or fermented foods. Once ingested, the toxin is absorbed from the gastrointestinal tract and enters the bloodstream, where it targets the neuromuscular junction by blocking the release of acetylcholine, the neurotransmitter responsible for muscle contraction. This results in a descending, symmetric flaccid paralysis that can affect multiple body systems. The illness typically begins 12 to 36 hours after ingestion of contaminated food, though onset can range from 6 hours to 10 days. Early symptoms often include nausea, vomiting, abdominal cramps, and diarrhea, followed by characteristic neurological signs such as blurred or double vision (diplopia), drooping eyelids (ptosis), difficulty swallowing (dysphagia), slurred speech (dysarthria), dry mouth, and facial weakness. The paralysis progresses in a descending pattern, potentially affecting the muscles of the trunk and extremities. In severe cases, respiratory muscle paralysis can occur, requiring mechanical ventilation and intensive care support. Autonomic dysfunction, including constipation, urinary retention, and orthostatic hypotension, may also be present. Treatment centers on early administration of botulinum antitoxin, which neutralizes circulating toxin and can halt disease progression but does not reverse existing paralysis. Supportive care, particularly respiratory support, is critical and may be required for weeks to months as nerve terminals regenerate. With prompt diagnosis and modern intensive care, the case fatality rate has decreased significantly but remains approximately 5–10%. Full recovery is possible but may take weeks to months. Prevention focuses on proper food handling, preparation, and storage practices.

Common questions about Foodborne botulism