Botulism

Synonyms

3

Overview

Botulism is a rare but serious illness caused by a bacterium called Clostridium botulinum,. It produces a toxin that affects your nerves. Three common forms of botulism are:

  • Foodborne botulism. The harmful bacteria thrive and produce the toxin in environments with little oxygen, such as in canned food as well as it comes from eating food contaminated with the toxin,
  • Wound botulism. If these bacteria get into a cut, they can cause a dangerous infection that produces the toxin.
  • Infant botulism. This most common form of botulism begins after Clostridium botulinum bacterial spores grow in a baby's intestinal tract. It typically occurs between the ages of 2 months and 8 months. It is caused by consuming the spores of the bacteria, usually from honey.

All types of botulism can be fatal and are considered medical emergencies.

Symptoms

Foodborne botulism:
Signs and symptoms of foodborne botulism typically begin between 12 and 36 hours after the toxin is absorbed. But, the start of symptoms can range from a few hours to several days, depending on the amount of toxin ingested. Signs and symptoms of foodborne botulism include:

  • Difficulty swallowing or speaking
  • Dry mouth
  • Facial weakness on both sides of the face
  • Blurred or double vision
  • Drooping eyelids
  • Trouble breathing
  • Nausea, vomiting and abdominal cramps
  • Paralysis
  • Wound botulism

Wound botulism signs and symptoms include:

  • Difficulty swallowing or speaking
  • Facial weakness on both sides of the face
  • Blurred or double vision
  • Drooping eyelids
  • Trouble breathing
  • Paralysis
  • Infant botulism

Infant botulism:
If infant botulism is related to food, such as honey, problems generally begin within 18 to 36 hours after the toxin enters the baby's body. Signs and symptoms include:

  • Constipation (often the first sign)
  • Floppy movements due to muscle weakness and trouble controlling the head
  • Weak cry
  • Irritability
  • Drooling
  • Drooping eyelids
  • Tiredness
  • Difficulty sucking or feeding
  • Paralysis

Certain signs and symptoms usually don't occur with botulism. For example, botulism doesn't generally increase blood pressure or heart rate, or cause fever or confusion. However, sometimes, wound botulism may cause fever.

Causes

Infant botulism:
Babies get infant botulism after consuming spores of the bacteria, which then grow and multiply in their intestinal tracts and make toxins. The source of infant botulism may be honey, but it's more likely to be exposure to soil contaminated with the bacteria.

Foodborne botulism:
The source of foodborne botulism is often home-canned foods that are low in acid, such as green beans, corn and beets. When you eat food containing the toxin, it disrupts nerve function, causing paralysis.

Wound botulism:
When C. botulinum bacteria get into a wound — possibly caused by an injury you might not notice — they can multiply and produce toxin. Wound botulism has increased in recent decades in people who inject heroin, which can contain spores of the bacteria. In fact, this type of botulism is most common in people who inject black tar heroin.

Are there benefits to botulinum toxin?
Botulinum toxin has been used to reduce facial wrinkles by preventing contraction of muscles beneath the skin and for medical conditions, such as eyelid spasms and severe underarm sweating. However, there have been rare occurrences of serious side effects, such as muscle paralysis extending beyond the treated area, with the use of botulinum toxin for medical reasons.

Prevention

Prevention of botulism is based on good food preparation (particularly preservation) practices and hygiene. Botulism may be prevented by inactivation of the bacterial spores in heat-sterilized, canned products or by inhibiting growth in all other products. Commercial heat pasteurization (vacuum packed pasteurized products, hot smoked products) may not be sufficient to kill all spores and therefore safety of these products must be based on preventing growth and toxin production. Refrigeration temperatures combined with salt content and/or acidic conditions will prevent the growth or formation of toxin. If exposure to the toxin via an aerosol is suspected, in order to prevent additional exposure to the patient and health care providers, the clothing of the patient must be removed and stored in plastic bags until it can be washed with soap and water. The patient must shower thoroughly.

Food and water samples associated with suspect cases must be obtained immediately, stored in proper sealed containers, and sent to reference laboratories in order to help prevent further cases.

Prepare and store food safely:

  • Don't eat preserved food if its container is bulging or if the food smells spoiled. However, taste and smell won't always give away the presence of C. botulinum. Some strains don't make food smell bad or taste unusual.
  • If you wrap potatoes in foil before baking them, eat them hot or store them in the refrigerator — not at room temperature.
  • Store oils infused with garlic or herbs in the refrigerator.

Infant botulism:
Avoid giving honey (even a tiny bit) to babies under the age of 1 year.
Wound botulism:
To prevent wound botulism and other serious bloodborne diseases, never inject or inhale street drugs.

Diagnosis

To diagnose botulism, your doctor will check you for signs of muscle weakness or paralysis, such as drooping eyelids and a weak voice. Your doctor will also ask about the foods you've eaten in the past few days, and ask if you may have been exposed to the bacteria through a wound.

In cases of possible infant botulism, the doctor may ask if the child has eaten honey recently and has had constipation or sluggishness.

Analysis of blood, stool or vomit for evidence of the toxin may help confirm an infant or foodborne botulism diagnosis, but because these tests may take days, your doctor's clinical examination is the primary means of diagnosis.

Prognosis

Botulism can result in death from respiratory failure. However, in the past 50 years, the rate of death from botulism has fallen from about 60% to 8%. Unfortunately, to survive, a patient with severe botulism may require not only a breathing machine but also intensive medical and nursing care for several months.

Patients who survive an episode of botulism poisoning may experience fatigue and shortness of breath for years, and long-term therapy may be needed to aid recovery.

Treatment

For cases of foodborne botulism, doctors sometimes clear out the digestive system by inducing vomiting and giving medications to induce bowel movements. If you have botulism in a wound, a doctor may need to remove infected tissue surgically.

Antitoxin:
If you're diagnosed early with foodborne or wound botulism, injected antitoxin reduces the risk of complications. The antitoxin binds to the toxin that's still circulating in your bloodstream and keeps it from harming your nerves. The antitoxin cannot, however, reverse the damage that's been done. Fortunately, nerves do regenerate. Many people recover fully, but it may take months and extended rehabilitation therapy.

Antibiotics:
Antibiotics are recommended for the treatment of wound botulism only. 

Breathing assistance:
If you're having trouble breathing, you will probably need a mechanical ventilator for up to several weeks as the effects of the toxin gradually lessen. The ventilator forces air into your lungs through a tube inserted in your airway through your nose or mouth.

Rehabilitation:
As you recover, you may also need therapy to improve your speech, swallowing and other functions affected by the disease.

The respiratory failure and paralysis that occur with severe botulism may require a patient to be on a breathing machine (ventilator) for weeks and may require intensive medical and nursing care. After several weeks, the paralysis slowly improves as axons in the nerves are regenerated.

The bacterium Clostridium botulinum is the same bacterium that is used to produce Botox, a pharmaceutical used as injections for clinical and cosmetic use. However, what is used in Botox treatments is the purified and diluted A neurotoxin. Treatment is administered in the medical setting, tailored according to the needs of the patient and is usually well tolerated. Occasionally there may be some side effects.

Approved treatments.

  • botulism antitoxin heptavalent (A, B, C, D, E, F, G) (Equine) -FDA-approved indication: Treatment of symptomatic botulism following documented or suspected exposure to botulinum neurotoxin serotypes A, B, C, D, E, F, or G in adults and pediatric patients  
  • Botulism immunoglobulin (BabyBIG ) - FDA-approved indication: Indicated for treatment of infant botulism caused by type A or type B Clostridium botulinum.

     

    Resources

    Refer to Research Publications.