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Foodborne Botulism

Foodborne botulism is a rare but serious illness caused by bacteria. The bacteria can get into your body through food you eat. It then makes a toxin that causes muscles in your body to not work (paralysis). This can cause problems with swallowing, breathing, vision, and movement. Botulism is a medical emergency. It can cause death due to loss of breathing if not treated right away.

How to say it

BAH-choo-lihz-uhm

What causes foodborne botulism?

Botulism is caused by Clostridia bacteria. There are different causes of botulism. Botulism in food happens when you eat the bacteria in infected food.

The bacteria make spores that help them grow in certain foods. They can grow in foods that are kept in low oxygen. This includes foods canned or preserved at home. Foods most at risk are those low in acid, sugar, or salt. This includes most vegetables and all types of meat. Other foods at risk include oils infused with herbs or garlic. It also includes fermented foods such as pickles. And it includes Alaska native foods such as fermented fish, beaver, seal, walrus, and other meats. If any of these foods are prepared with unsafe methods, they are at risk of growing botulism bacteria.

Symptoms of foodborne botulism

With botulism from food, symptoms can start 18 to 36 hours after eating the food. But they may start as soon as 6 hours or as late as 10 days after eating contaminated food.

Symptoms may start with:

  • Nausea

  • Vomiting

  • Diarrhea

  • Dry mouth

  • Sore throat

Then, more symptoms are caused by muscle paralysis. They can include:

  • Trouble swallowing

  • Slurred speech

  • Feeling weak all over

  • Double vision

  • Blurry vision

  • Eye movements you can’t control

  • Drooping eyelids

  • Dry mouth

  • Tongue that feels thick

  • Trouble breathing

  • Trouble urinating

  • Constipation

Diagnosing foodborne botulism

Your healthcare provider will ask about your symptoms and give you a physical exam. You will have a blood test to look for the toxin and bacteria. If the healthcare provider thinks you may have botulism, they will start treating you right away.

You may need more tests to see if you have a condition that seems like botulism. Conditions that can cause similar symptoms include stroke, opioid overdose, and myasthenia gravis. You may have tests such as:

  • MRI or CT scan of the brain to check for stroke

  • Spinal fluid test to check for infection

  • Tests to check your nerve and muscle function

  • Tensilon test to check for myasthenia gravis

Treatment for foodborne botulism

Botulism is treated with a medicine called antitoxin. This medicine stops the toxin from doing more harm. But it does not reverse all the damage the toxin has already done. You may need to stay in the hospital for weeks or months during and after treatment. If you have trouble breathing, you may need to be on a breathing machine (ventilator). You will use this machine until you can breathe on your own. Muscle paralysis can get better over time.

Possible complications of foodborne botulism

If untreated, symptoms can get worse and lead to death from breathing failure. Botulism can cause paralysis that can last for weeks or months. After treatment, you may be tired and short of breath for months or years. You may need physical therapy to help you get better over time.

How to prevent foodborne botulism

The CDC says that foods preserved at home are the most common cause of botulism in the U.S. If you preserve or ferment foods at home, follow the instructions in the USDA Complete Guide to Home Canning.

Don't taste any food that has been canned, jarred, or fermented at home and looks damaged, swollen, or gives off gas when opened. Even a small amount of infected food can cause illness.

When to call your healthcare provider

Call your healthcare provider right away if you have any of these:

  • Fever of 100.4°F (38°C) or higher, or as advised by your provider

  • Redness, swelling, or fluid leaking from a wound that gets worse

  • Pain that gets worse

  • Symptoms that don’t get better, or get worse

  • New symptoms

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