The Anatomy of Botulism
Why Infants Can’t Have Honey
Why is botulism scary enough that infants under 1 year of age cannot have honey? Why is botulism in honey not a concern for older children and adults? It can also occur in canned goods that have gone bad or were not processed correctly, and these can make an adult extremely ill. It all comes down to the anatomy of botulism and mechanism of disease.
Botulism is from a bacterium called clostridium botulinum. This bacterium is found in the soil and many other places in the form of spores. A spore is a protective coating around the bacteria making it dormant and able to withstand environments that the normal active bacteria wouldn’t, such as surviving the antimicrobial properties of honey. These spores can only activate under certain conditions, otherwise they can lay dormant for years. In order for the spores to activate, the environment must have a certain temperature range, moisture, low acid, low salt, low sugar, and lack of oxygen. These must nearly all be met. When clostridium botulinum multiplies under the right conditions it produces a toxin which we call botulinum toxin. The toxin can also come from clostridium butyricum or clostridium baratii, but these are not as common. This toxin is what truly makes a person suffering from botulism ill because it paralyses muscles including those needed to breathe.
The digestive tract of most healthy humans does not give the right conditions for botulism, but it can reproduce in the gut of an infant less than 1 year of age. This is because they have not developed enough microflora to compete against the botulinum bacteria and they have lower levels of bile acids. (Caya, Agni, & Miller, 2004) One year is the mark at which a child should be safe from tiny amounts of ingested botulism spores. In fact, 90% of all confirmed botulism cases (including those in adults) are in infants younger than 6 months. (Yetman, 2020) Because of the nature of the spores activating in the intestine, infants may not display signs until up to a month after exposure. Other cases of botulism typically show symptoms after 12-36 hours.
Recent studies have suggested that about 2% of the honey produced across the world contains botulism spores, but older studies give ranges of up to 25% of honey being contaminated. (CDC.GOV, 2019) While this is a tiny percentage, botulism can easily kill a baby and is not worth the risk. Because botulism is found naturally in many places including soil, infants can also become ill from it without any exposure to honey. It is important to know the signs which include constipation, poor feeding, drooping eyelids, pupils that are slow to react to light, face showing less expression than usual, weak cry that sounds different than usual, and difficulty breathing. They may not have all the signs at the same time, but it is important for them to be taken immediately to the emergency room.
Because of the severity of botulism, a doctor must begin treatment immediately upon suspicion of botulism even before receiving laboratory confirmation. Treatment includes the administration of an antitoxin against botulinum toxin. This antitoxin will not affect the ability to confirm that botulism is the cause as it does not kill or prevent the growth of clostridium botulinum in the intestine. It only neutralizes toxin that is present in the blood thus lessening the severe effects of the toxin. It does not reverse the paralysis and damage already caused, but it will halt the progression of the symptoms.
A similar antitoxin is used as treatment for other types of botulism which can happen in older children and adults. The main cause of these botulism cases is foodborne. This can be from home canned vegetables that were not brought to a high enough temperature during the canning process or commercially canned goods that were contaminated. Remember the warning to never eat food from dented or bulging cans? Yep, botulism. It can also infect a wound usually from a traumatic injury or intravenous drug use. Any cases of botulism can be fatal regardless of age or cause and must be treated quickly.
The best choice is to avoid botulism in any way possible. The toxin can be killed through proper food preparation that includes heating to 185℉. However the spore is very heat resistant to 250℉. Because of this, you should still avoid giving honey even in the form of baked goods or other food dishes to an infant. One-fifth of infant botulism cases result from ingesting honey. Food preservation needs to meet certain criteria. Fermentation needs a proper salt content or acid level. Even smoked meats must be kept below a certain temperature for storage. Low-acid vegetables such as asparagus must be pressure-canned or they have a high risk of developing botulism. Wound botulism has become more common with intravenous drug use as injection sites can become infected. In some cases, the injecting of botulinum toxin (Bo-tox) may have too much toxin and cause illness.
Because of the spore-causing anatomy of botulinum bacteria, honey is dangerous to infants in any form, even cooked. However, honey is far from the only cause of botulism. By knowing and understanding the signs and symptoms of botulism, you can get help to someone suffering from the botulinum toxin.
Caya, J. G., Agni, R., & Miller, J. E. (2004). Clostridium botulinum and the Clinical Laboratorian: A Detailed Review of Botulism, Including Biological Warfare Ramifications of Botulinum Toxin. Archives of Pathology and Laboratory Medicine, 653-662.
CDC.GOV. (2019, August 19). Botulism. Retrieved from Centers for Disease Control and Prevention: https://www.cdc.gov/botulism/index.html
Yetman, D. (2020, April 16). What’s the Connection Between Botulism and Honey? Retrieved from Healthline: https://www.healthline.com/health/botulism-honey#link-to-honey
Originally published in December2021/January2022 issue of Backyard Beekeeping and regularly vetted for accuracy.