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What is it?

Botulism is a serious form of food poisoning that can cause death and paralysis. Bacteria found in soil and dust called clostridium botulinum make a poison that can cause a rare but a serious paralytic illness. Eating foods that contain botulism toxin cause foodborne botulism. You can also get botulism from an infected wound. All forms of botulism can cause paralysis and death. 

How does it spread?

Botulism mostly results when certain foods are stored or prepared improperly.

The most common way of getting botulism is by eating or drinking contaminated foods and beverages, like:

  • Improperly prepared low-acid, home-canned foods (like corn, peas, asparagus, beets, salmon, spaghetti sauce, green beans, mushrooms, peppers).
  • Improperly smoked fish.
  • Improperly prepared raw marine mammal meat (like whale, walrus, seal).
  • Non-refrigerated storage of low-acid fruit juices (like carrot juice).
  • Leftover baked potatoes stored in aluminum foil.

C. botulinum bacteria are heat-resistant and can survive high temperatures. The bacteria can grow in a moist, oxygen-free environment, so home canning or bottling provides the perfect conditions for the bacteria to multiply and produce the toxin, unless the food is properly canned or heat processed.

Honey (which naturally contains C. botulinum) has been linked to infant botulism. While the bacteria can't grow or produce toxins in honey, they can grow and produce toxins in a baby's intestine.

What are the signs and symptoms?

Symptoms of botulism may include

  • Fatigue, weakness and dizziness.
  • Blurred or double vision.
  • Dryness of the mouth, throat and nose and difficulty in swallowing and speaking.
  • Headache.
  • Nausea, vomiting, abdominal pain, and less commonly diarrhea.
  • Paralysis that starts in the shoulders and arms and moves down the body.

Severe cases can cause paralysis of the breathing muscles, respiratory or heart failure and death.

Symptoms of foodborne botulism begin 12 to 36 hours after eating contaminated food; however, it can start as quickly as 6 hours after exposure, or as long as 10 days later.

Symptoms can last several weeks and then slowly go away over several months.

How is it treated?

Botulism is a medical emergency. Early diagnosis and treatment is very important since death from respiratory failure can happen within 1 to 10 days.  Anyone with signs, symptoms or history of botulism should be hospitalized immediately. A physician or nurse practitioner will rule-out other conditions that have similar signs and symptoms and have diagnostic tests done to confirm the diagnosis.

Foodborne botulism is treated with botulism antitoxin and intensive medical and nursing care in hospital.

Is botulism contagious?

Botulism is not spread from person to person.

How can it be prevented?

Proper hygiene and safe food handling are key to preventing the spread of foodborne illnesses, including botulism.

There are a number of precautions you can take to reduce the risk of becoming infected with botulism:

  • Never eat food from cans that are dented, leaking or having bulging ends. The food may not look spoiled, but it may still contain the toxin.
  • When canning foods at home, be sure to process all low-acid products (for example, vegetables, mushrooms and seafood) in a pressure canner and follow the manufacturer's instructions closely.
  • Take precautions with home-prepared foods stored in oil (for example, vegetables, herbs and spices). If these products are prepared using fresh ingredients, they must be kept refrigerated and for no more than 10 days.
  • If you purchase the products described above at fairs, farmer's markets or roadside stands, or if you receive them as a gift, check when they were prepared and discard them if they are more than a week old.
  • Don’t use aluminum foil to wrap potatoes or other vegetables for baking unless the vegetables will be cooked and eaten right away or unwrapped and refrigerated right after they’re cooked.
  • Don’t feed honey (even pasteurized honey) to children under one year old. The bacteria that cause botulism cannot grow or make toxins in the honey, but they can grow and make toxins in the baby's body.
  • Date and label preserves and canned goods, and strictly follow proper canning requirements.
  • Keep all work surfaces, food, utensils, equipment and hands clean during all stages of the canning process.
  • Refrigerate all foods labelled "keep refrigerated."

Health Care Providers

Suspected cases are reportable to the Health Unit immediately by telephone.