Botulism

Clostridium botulinum bacteria are found in soil, dust, and river or sea sediments. The bacteria themselves aren't harmful, but they can produce highly poisonous toxins when deprived of oxygen such as in closed cans or bottles, stagnant soil or mud, or occasionally the human body.

There are three main types of botulism:

• food-borne botulism when someone eats food containing the toxins because it hasn't been properly canned, preserved or cooked
• wound botulism when a wound becomes infected with the bacteria, usually as a result of injecting illegal drugs contaminated with the bacteria, such as heroin, into muscle rather than a vein
• infant botulism when a baby swallowsa resistant form of the bacteria, called a spore, incontaminated soil orfood, such as honey. Thesespores are harmless to older children and adults because the body develops defences against them from about one year of age

All these types of botulism are very rare in the UK, but occasional cases do occur.