Botulism (Clostridium Botulinum)

Botulism is a rare but serious illness caused by bacteria called Clostridium botulinum. The bacteria produce a poison (toxin) that disrupts your body’s nervous system. If left untreated, botulism can be deadly.

There are three main types of botulism:

• Foodborne botulism: This type happens from eating food contaminated with Clostridium botulinum bacteria.
• Wound botulism: You get this type when C. botulinum bacteria infect a wound and produce the toxin there.
• Infant botulism: This form affects children under 1 year old. They get it when they eat something that contains the spore form of the bacteria.

There are other types of botulism, too. But they’re either extremely rare or theoretical, meaning experts haven’t seen them happen in real-world settings.

Symptoms of botulism

The symptoms of botulism can vary somewhat based on how the poison gets in your body.

Foodborne botulism

The symptoms may start as early as a few hours after eating contaminated food, or as late as two weeks. Common symptoms include:

• Abdominal pain or discomfort
• Blurred or double vision
• Dilated pupils (mydriasis)
• Dizziness
• Drooping eyelid (ptosis)
• Dry or sore throat (because your body isn’t making mucus like it should)
• Facial muscle paralysis
• Nausea or vomiting
• Swollen belly (distended abdomen)
• Trouble swallowing (dysphagia)
• Trouble speaking (dysarthria)

As botulinum poisoning worsens, it causes paralysis that spreads down your body. The paralysis affects both sides of your body, and it only affects movement. You won’t have tingling or numbness in the affected areas. Other symptoms can include:

• Constipation and ileus (blockages because your intestines aren’t pushing food through)
• Low blood pressure (hypotension) and slow heart rate (bradycardia)
• Urinary retention
• Weakness in breathing muscles, which makes you have trouble breathing (dyspnea)

Wound botulism

Wound botulism symptoms are similar to foodborne botulism symptoms. But there are some key differences:

• No early stomach-related symptoms
• Possibility of having a fever
• Weakness or paralysis in muscles around the infected wound
• Symptoms appear after about one to three weeks

IMPORTANT: Botulism poisoning is rare. But if you or a child you care for has the symptoms of it, you should treat it like a medical emergency. Call 911 (or your local emergency number) right away, or go to the nearest hospital or emergency room.

Botulism causes

Botulism happens because of a toxin from Clostridium botulinum bacteria. This bacterium spreads itself in spore form, and those spores live in soil worldwide.

Foodborne botulism happens when the bacteria make the toxin in your food. When you eat the contaminated food, it poisons you. Home-canned foods are one of the more common sources of foodborne botulism. But store-bought foods, canned and otherwise, can sometimes cause it, too.

Wound botulism can happen when Clostridium botulinum infects any wound. Injection drug use, especially black tar heroin, is one of the most common causes. But it can also happen from compound fractures, dental work, gunshot wounds and more.

When conditions are right, the spores return to their bacterial form, which lets them multiply and make the toxin.

Conditions that let the bacteria grow and make their toxin include:

• Little or no oxygen
• Low acidity
• Little or no sugar or salt
• Food that’s uncooked or undercooked
• Storage that’s too warm

Rare causes of botulism

Rare causes of botulism include:

• Medical care (iatrogenic): Botulinum toxin has medical uses, like for migraine headaches, movement disorders or even excessive sweating. This is rare because it usually takes very large doses. Botulism can also sometimes happen with care from unlicensed medical providers.
• Intestinal colonization: Botulism-causing bacteria from the environment can end up in your digestive system among the healthy, normal bacteria that should be there. Once they do, the toxin they make can poison you from inside. This is how honey can be a source of infection for infants under a year of age.
• Inhalation: Breathing in botulinum toxin can be extremely deadly. But that doesn’t happen naturally. One possible way it could happen is terrorism. But this is extremely rare and no terrorist group has ever succeeded in using it.

Complications of botulism

The most dangerous complication of botulism is when this condition paralyzes the muscles you use to breathe. That can be deadly without fast treatment. The paralysis from botulism is temporary, but it can last for weeks or even months.

Other complications can vary depending on how severe your case is and the type of botulism you have. They can include:

• Extreme tiredness (fatigue)
• Long-term weakness
• Aspiration pneumonia
• Nervous system issues

Your healthcare provider is the best person to tell you more about what to expect in your case.

How doctors diagnose botulism

Healthcare providers may suspect botulism based on your symptoms and how you answer their questions. In particular, questions about what you’ve eaten recently or any food-related symptoms you experienced can be very important. Your provider will also do a physical exam and a neurological exam.

Lab testing is essential to confirming a botulism diagnosis. Your provider will likely want to run tests on your poop (stool), blood or vomit.

Botulism shares symptoms with conditions like strokes, meningitis and Guillain-Barré syndrome. Your provider may recommend other tests to rule those conditions out. Examples of tests they might run include CT scans or an MRI of your brain, a spinal tap (lumbar puncture) or electromyography.

How is botulism treated?

The main treatments for botulism aim to stop the toxin quickly and prevent its life-threatening effects. Treatments for foodborne botulism in people older than 12 months include:

• Botulinum antitoxin: This is an antidote that neutralizes any toxin it finds in your body.
• Breathing support: Healthcare providers may insert a breathing tube and use a ventilator if you can’t breathe on your own because of paralysis.

For infant botulism, the main treatment is botulinum immune globulin (baby BIG). It contains antibodies against botulinum toxin. It treats babies with infant botulism.

For wound botulism, antitoxin and breathing support are also vital to your care. Your provider may also recommend procedures to debride (clean) the infected wound and using antibiotics to get rid of any remaining bacteria.

What can I expect if I have botulism?

Botulism can be unpleasant and scary, but almost everyone with it will make a full recovery. The sooner you get a diagnosis and treatment, the sooner you’ll recover. It’s also common for people who survive botulism to need supportive care until their paralysis goes away.

Recovering most of your strength should happen within the first few months. But you’ll likely see continuing improvements for up to a year.

Can botulism be prevented?

Botulism is usually preventable with the right precautions, especially the foodborne type. The most important things you can do to prevent it include:

• Refrigerate food within two hours after cooking. Doing so keeps the bacteria from making spores.
• Cook food thoroughly. Heat above 212 degrees Fahrenheit (100 degrees Celsius) will kill botulism-causing bacteria after 10 minutes. Heat above 176 degrees F (80 degrees C) will kill the bacteria after 20 minutes.
• Throw away cans of food that look like they’re bulging or swelling from the inside. That can be a sign of the bacteria at work.
• Use proper canning and sterilizing practices. Sterilize home-canned foods in a pressure cooker at 250°F (121°C) for 30 minutes.
• Throw away foul-smelling preserved foods. Botulism-causing bacteria often make even preserved foods smell bad.

To prevent wound botulism:

• Practice proper wound care
• If you give yourself injections, make sure you practice good handwashing and safe needle use
• Avoid drugs like black tar heroin, which have a contamination risk because of how they’re made
• Don’t ignore signs of wound infection that don’t go away after a couple days
• Only get botulinum toxin treatments from licensed healthcare providers