Botulism
Botulism is a serious bacterial illness that leads to paralysis, and is caused by a toxin that affects the body’s nerves. Botulism toxins are one of the most lethal known substances and are included among potential bioterrorism threats. The bacterial spores exist widely in the environment and can grow and produce toxins in anaerobic conditions.
Botulism occurs naturally in three forms:
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food-borne botulism, an intoxication caused by eating food that containing botulism toxins;
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intestinal botulism, caused by the consumption of botulism spores, which then germinate into bacteria and release toxins within the intestines of adults (adult intestinal toxaemia) or babies under one year of age (infant botulism); and
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wound botulism, caused by spores infecting a wound, germinating into bacteria, then releasing toxins.
There are two other forms of the disease that do not occur naturally:
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inhalation botulism, caused by inhaling toxins that have been accidentally or deliberately released in the form of aerosols (e.g. in bioterrorism events), and
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iatrogenic botulism, the most recent human-made form of botulism, which may occur as an adverse event after the administration of toxins for medical or cosmetic reasons.
Food-borne botulism is the most common form of the disease. It is frequently caused by inadequately processed, often home-canned, preserved or fermented foods (e.g. vegetables, meat or fish). Symptoms of botulism are characterised by muscle weakness that can lead to respiratory failure. The symptoms may be very severe and require intensive-care treatment, as well as the administration of an antitoxin. Even where these treatments are available, complete recovery usually takes weeks to months, and 5–10% of cases are fatal.
Protective measures
To prevent botulism, it is essential to take care when canning food, avoid consuming food from canned food that appear swollen as this could be a sign of gas produced by bacteria, and store food that has not been fully processed in the refrigerator. Boiling home-canned foods for at least ten minutes before eating can deactivate the botulism toxin.