Botulism history and symptoms

Food-borne and wound botulism

 * Classic symptoms of food-borne botulism usually occur between 12–36 hours after consuming the botulinum toxin. However, they can occur as early as 6 hours or as late as 10 days after.
 * Wound botulism has a longer incubation period, usually between 4–14 days.

Common symptoms of either form usually include dry mouth, difficulty swallowing, slurred speech, drooping eyelids, muscle weakness, double and/or blurred vision, vomiting, blatter and sometimes diarrhea. These symptoms may progress to cause paralytic ileus with severe constipation, and eventually body paralysis. The respiratory muscles are affected as well, which may cause death due to respiratory failure. These are all symptoms of the muscle paralysis caused by the bacterial toxin.

In all cases illness is caused by the toxin made by C. botulinum, not by the bacterium itself. The pattern of damage occurs because the toxin affects nerves that are firing more often.

Infant botulism
Infant botulism (first recognized in 1976) is the most common form of the ailment in the United States, but is rarely diagnosed in other countries. It affects about 100 infants per year in the United States, with the majority in the state of California (50–60%). Infants less than 12 months of age are susceptible, with 95% of cases occurring between the ages of 3 weeks and 6 months of age at presentation. The mode of action of this form is through colonization by germinating spores in the gut of an infant. The first symptom is usually constipation, followed by generalized weakness, loss of head control and difficulty feeding. Like the other forms of botulism, the symptoms are caused by the absorption of botulinum toxin, and typically progress to a symmetric descending flaccid paralysis. Death is the eventual outcome unless the infant receives artificial ventilation.

Honey, corn syrup, and other sweeteners are potentially dangerous for infants. This is partly because the digestive juices of an infant are less acidic than older children and adults, and may be less likely to destroy ingested spores. In addition, young infants do not yet have sufficient numbers of resident microbiota in their intestines to competitively exclude C. botulinum. Unopposed in the small intestine, the warm body temperature combined with an anaerobic environment creates a medium for botulinum spores to germinate, divide and produce toxin. Thus, C. botulinum is able to colonize the gut of an infant with relative ease, whereas older children and adults are not typically susceptible to ingested spores. C. botulinum spores are widely present in the environment, including honey. For this reason, it is advised that neither honey, nor any other sweetener, be given to children until after 12 months. Nevertheless, the majority of infants with botulism have no history of ingestion of honey, and the exact source of the offending spores is unclear about 85% of the time. Spores present in the soil are a leading candidate for most cases, and often a history of construction near the home of an affected infant may be obtained.