Botulism is an infectious disease caused by a type of bacteria known as Clostridium botulinum, or C. botulinum. This microorganism produces a toxin known as botulinum toxin, which affects the nervous system. While botulism is rare, it’s very serious and potentially even fatal. 

Botulism can affect people of any age, and most commonly occurs after eating food that has been improperly stored. Because their immune systems aren’t yet fully developed, babies are also uniquely vulnerable to getting botulism from certain foods that don’t affect children or adults. 

By learning more about botulism and how it’s transmitted, you can help to prevent this potentially devastating disease from affecting your family.

What is Clostridium botulinum?

C. botulinum is actually common in the environment. It can be found in soil, dust, and water around the world. Fortunately, even though most people are exposed to it at some point, this type of bacteria usually can’t grow inside the human body, which helps to prevent it from causing disease.

To grow and divide, C. botulinum needs a low-oxygen environment. Conditions in the human body usually don’t meet its needs. However, when they’re not in the right type of environment to grow, these bacteria can produce spores, which are dormant bacteria encased in thick shells. The spores are highly resistant to damage, allowing C. botulinum spores to survive for long periods of time in a wide variety of environments.

C. botulinum produces a toxin known as botulinum toxin. This toxin acts to interrupt communication between nerves and muscles. Once botulinum toxin binds to a neuron (a nerve cell), it acts to prevent the release of a substance called acetylcholine. Normally, when acetylcholine contacts receptors on a muscle cell, this triggers activation of the muscle. By blocking the release of acetylcholine, botulinum toxin prevents the nerve from activating the muscle. This causes the muscle to become weak or even completely paralyzed.

When botulinum toxin spreads throughout the body in the bloodstream, it leads to widespread muscle weakness. If the dose is high enough, the toxin can paralyze muscles that are necessary for life, such as the breathing muscles. This is how botulism can be fatal. It takes only a very small amount of botulinum toxin to cause serious health effects or even death.

Injections of extremely tiny amounts of botulinum toxin are actually used as treatments in certain areas of medicine. When used in this way, the toxin is typically referred to as “botox.” Botox injections can be used to treat muscle spasms or overly tight muscles that are causing symptoms. They’re also used for cosmetic purposes, to paralyze certain facial muscles and prevent them from causing wrinkles in the skin. As long as it’s properly manufactured and injected, the amount of botulinum toxin in a botox injection is not enough to be dangerous. In these products, the toxin is diluted to make it safer.

How do people get botulism?

The disease known as botulism results from exposure to botulinum toxin. This toxin is not produced by the spores of C. botulinum. It’s only produced when the bacteria are actively growing.

The most common way to get botulism is from food that has been improperly stored in a can or jar. Once such a container is sealed, this provides the low-oxygen environment that C. botulinum needs to grow. As the bacteria become active, they produce botulinum toxin. When a person eats the contaminated food, they also consume the toxin, which is absorbed into the bloodstream and spreads throughout the body.

Usually, botulism is caused by consuming the toxin itself, rather than by the bacteria themselves growing inside of the body. In fact, in most people, C. botulinum is not able to grow inside the digestive tract. Because of this, if you eat food that contains spores of the bacteria, this will not generally lead to botulism.

However, the environment inside of a baby’s digestive tract is different. In a baby under the age of one year, C. botulinum is able to grow and divide inside of the digestive tract. This is because the immune system has not yet developed enough to provide defenses against the bacteria. This means that babies can get botulism from eating food that contains C. botulinum spores. 

While most adults and children over one year old are protected against becoming infected by C. botulinum spores, certain people in these age groups may be vulnerable to getting botulism in this way. This includes people who have serious chronic diseases, especially conditions that affect the immune system and/or the digestive tract.

How do you know if a person has botulism?

After ingesting food that’s contaminated with botulinum toxin, symptoms usually take about one to three days to develop. This is because it takes time for the toxin to enter into nerve cells and bind to the proteins involved in acetylcholine release. Once this has happened, then the muscles that are normally activated by the affected nerve cells will become weak, as the nerve cells lose their ability to communicate with the muscles.

In many cases, the first signs of botulism are nausea, vomiting, and abdominal pain. These symptoms are the result of irritation of the digestive tract by the toxin. At this stage, it can be difficult to distinguish botulism from other types of food-borne infections, as the symptoms are similar.

Within a few hours to a day or two, neurological symptoms will start to appear. The first symptoms are generally related to the eyes and face, such as double vision, drooping eyelids, trouble swallowing, and slurred speech. As the toxin continues to enter more nerve cells, then weakness of the arms and legs may develop. Constipation and trouble urinating often occur, because the muscles of the digestive system and bladder are also affected. The most serious symptom of botulism is trouble breathing, which can quickly lead to death if not treated promptly.

In a baby, parents often notice that the child is severely constipated, and is also not wetting as many diapers as usual. The baby often has trouble feeding because they can’t suck or swallow properly, and they may drool more than usual. Their arms and legs may become weak or “floppy,” and they may also have a weak cry.

If you notice any of the potential signs of botulism in yourself or your child, seek immediate medical attention. It’s important to treat this disease as quickly as possible, to avoid serious health consequences.

Can botulism be treated?

The binding of botulinum toxin to proteins inside of nerve cells is irreversible. Once the toxin has bound to these proteins, there’s no known way to reverse its effects. However, doctors do have ways of treating patients with botulism.

Most patients are given a substance known as antitoxin through an IV. The antitoxin binds to any remaining botulinum toxin in the bloodstream, and this prevents the patient’s condition from getting worse. However, the antitoxin can’t remove any toxin that has already entered nerve cells and bound to proteins there. It therefore can’t reverse any muscle weakness or paralysis that has already occurred. It simply stops the progression of the disease.

Fortunately, recovery of the nerve cells occurs naturally over time. Nerve cells can grow new nerve endings, with proteins that are unaffected by the patient’s previous exposure to the toxin. As the new nerve endings grow, the nerve cells regain their ability to release acetylcholine and activate muscle cells, and the patient gradually recovers from the effects of botulism. The process of nerve cell recovery generally takes about 8 to 12 weeks, and additional weeks or months of physical therapy are often required for the patient to regain lost strength.

While waiting for this natural recovery process to occur, a patient with botulism may need supportive care. This means that doctors use treatments to address the problems created by the weak or paralyzed muscles. For example, if the muscles of breathing have been affected, then the patient may need to be on a ventilator, which is a machine that breathes for them. If they’re not able to swallow safely, then they will need artificial nutrition and hydration, meaning that they receive nutrients and fluids through an IV. This type of supportive care may be needed for several weeks, and often requires a patient to be in the intensive care unit (ICU).

Because of the development of the antitoxin as well as the use of supportive care, the mortality rate from botulism is currently only about 3 to 5%. The earlier the diagnosis is made, the better the chances that the patient will survive and make a full recovery.

How can you avoid botulism?

The most common way to get botulism is through eating food that’s been improperly stored. Most commonly, this occurs through food that was canned or jarred at home. If you choose to preserve your own food, it’s important to heat it to a high temperature for long enough to destroy any C. botulinum spores. This generally involves boiling or steaming the food for an extended period of time, or using a pressure canner. Both salt and acid prevent C. botulinum from growing, so adding one of these substances to your food before storing it can also help to make it safer. 

Store-bought canned or jarred foods can occasionally contain botulinum toxin, although this is rare. Avoid eating any food from a container that’s bulging or otherwise appears damaged, or any canned or jarred food that has an unusual smell or appearance – even if the expiration date on the can has not yet passed. 

It’s also important to ensure that food (including leftovers) is always properly refrigerated, and avoid eating food that is labeled “keep refrigerated” but has stayed warm for an extended period of time. This is because C. botulinum can’t grow at a colder temperature. If any spores have entered the food, refrigeration will ensure that the spores can’t activate and begin producing botulinum toxin.

For babies, it’s also important to avoid foods that may contain spores of C. botulinum. Because these spores are capable of growing and dividing inside of a baby’s digestive tract, eating the spores can lead to botulism in babies. Honey may contain C. botulinum spores, so it’s recommended that you avoid giving any honey to a baby under one year old. Older children and adults are naturally protected against getting botulism from bacterial spores, which means that it’s important to avoid giving any honey to babies even if other people have eaten from the same jar of honey without getting sick.

Botulism isn’t always a food-borne illness. There are also other ways that people can be exposed to the toxin. A contaminated wound can sometimes provide the conditions that allow C. botulinum to grow, leading to botulism. Keeping wounds clean and getting medical attention for any potential infection helps to avoid this. 

Babies can also ingest the spores through their environment (such as from soil or dust). In fact, in a baby with botulism, it’s not always clear where the spores came from. It’s not always possible to avoid this exposure, because C. botulinum is so common in the environment. If your baby develops possible symptoms of botulism, seek medical attention immediately, even if they haven’t eaten any risky foods like honey.

In rare cases, botulism can also develop when a person receives injections of too much botox. To avoid this, it’s important that, if you choose to receive botox injections, you always choose a reputable and licensed provider to perform the treatment.

Protecting your family from Clostridium botulinum infection

Botulism can lead to muscle weakness, paralysis, and death. You can protect yourself and your family by carefully following food safety practices while canning or jarring your own foods, avoiding eating foods from a can that appears damaged, refrigerating food promptly, and avoiding giving honey to a baby under one year old.  

There are also other types of infections that can be transmitted through food. Learning about these conditions empowers you to protect your family from food-borne infections (“food poisoning”).

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