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Clostridium botulinum in food


What is Clostridium botulinum?

Clostridium botulinum (C. botulinum for short) is a bacterium found in the environment. It grows in places where oxygen levels are low and can produce a very dangerous toxin.

What illness does it cause?

Foodborne botulism (caused by ingesting the bacteria’s toxin) and infant botulism (generally in children, caused by eating the bacteria’s spores).

Botulism is a nationally notifiable disease and must be reported to health authorities.

What are the symptoms?

Symptoms of foodborne botulism include vertigo, nausea, dry mouth, vomiting, double vision and trouble speaking and swallowing. Symptoms may progress to muscle weakness and constipation.

Symptoms of infant botulism include constipation, loss of appetite, weak sucking and crying, and muscle weakness including poor head control.

If not treated early, botulism can lead to paralysis and death. Symptoms usually start 18 to 36 hours after eating the food containing the toxin. The illness can last for weeks or months.

Who can get sick?

Anyone can get botulism although it is extremely rare in Australia. Generally only infants under 12 months old get infant botulism.

Where does it come from?

It can be found in soil and water, on plants and in the gut of fish, birds and mammals. Botulism spores are very tough and can survive a wide range of conditions (even boiling temperatures).

Common foods that can be contaminated with C. botulinum include home-canned and bottled foods and vacuum-packed foods that have not been processed properly; fermented, salted and smoked meat and seafood; and (in the case of infant botulism) honey

How can people get sick?

By eating food, water or soil contaminated with the bacteria or its toxin.

How can illness be prevented?

  • Care should be taken when preparing canned and bottled foods, vacuum-packed food (including sous vide cooking) and fermented, smoked or salted meat and fish products that will not be thoroughly cooked before eating
  • Throw away preserved or vacuum-packed food that is badly damaged, bulging or looks spoiled
  • Avoid giving honey to infants under 12 months old


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