Given that multiple people often consume food from the same source, it is common for more than a single person to be affected simultaneously. Symptoms usually appear 12–36 hours after eating, but can also appear within 6 hours to 10 days. Wound
Wound botulism results from the contamination of a wound with the bacteria, which then secrete the toxin into the bloodstream. This has become more common in intravenous drug users since the 1990s, especially people using black tar heroin and those injecting heroin into the skin rather than the veins. Wound botulism accounts for 29% of cases. Inhalation
Isolated cases of botulism have been described after inhalation by laboratory workers. Injection
Symptoms of botulism may occur away from the injection site of botulinum toxin. This may include loss of strength, blurred vision, change of voice, or trouble breathing which can result in death. Onset can be hours to weeks after an injection. This generally only occurs with inappropriate strengths of botulinum toxin for cosmetic use or due to the larger doses used to treat movement disorders. Following a 2008 review the FDA added these concerns as a boxed warning. Mechanism
The toxin is the protein botulinum toxin produced under anaerobic conditions (where there is no oxygen) by the bacterium Clostridium botulinum.
This may lead to respiratory compromise and death if untreated.Clinicians frequently think of the symptoms of botulism in terms of a classic triad: bulbar palsy and descending paralysis, lack of fever, and clear senses and mental status ("clear sensorium"). Infant botulism
Infant botulism (also referred to as floppy baby syndrome) was first recognized in 1976, and is the most common form of botulism in the United States. Infants are susceptible to infant botulism in the first year of life, with more than 90% of cases occurring in infants younger than six months. Infant botulism results from the ingestion of the C. botulinum spores, and subsequent colonization of the small intestine. The infant gut may be colonized when the composition of the intestinal microflora (normal flora) is insufficient to competitively inhibit the growth of C. botulinum and levels of bile acids (which normally inhibit clostridial growth) are lower than later in life.The growth of the spores releases botulinum toxin, which is then absorbed into the bloodstream and taken throughout the body, causing paralysis by blocking the release of acetylcholine at the neuromuscular junction. Typical symptoms of infant botulism include constipation, lethargy, weakness, difficulty feeding, and an altered cry, often progressing to a complete descending flaccid paralysis. Although constipation is usually the first symptom of infant botulism, it is commonly overlooked.Honey is a known dietary reservoir of C. botulinum spores and has been linked to infant botulism. For this reason, honey is not recommended for infants less than one year of age.