University of São Paulo: Untreated Botulism Can Lead to Organ Paralysis
Common in the United States, canned foods such as sausage and meat are not a tradition in Brazil, but the sale of artisanal palm hearts and other products that may contain botulinum toxin, which appears in cases of poorly stored or sanitized food, is not uncommon here. When they enter the body, the toxins produced by the microorganism Clostridium botulinum can cause total paralysis of the body. It should be noted, however, that this is not a contagious disease.
Bernadette Dora Gombossy de Melo Franco, professor at the Faculty of Pharmaceutical Sciences at USP, says that there are five types of the disease: “ Foodborne botulism, infant botulism, wound botulism, iatrogenic botulism and intestinal toxemia. The classic and most common form is caused by food, resulting from the ingestion of some of the various toxins pre-formed by this microorganism. The toxins are neurotoxins, that is, they act on nerve endings, inhibiting the release of neurotransmitters, which causes muscle paralysis. There are several types of botulinum toxins, the most common being types A, B and E. Many consider type A toxin to be the most potent that exists in nature.
In foodborne botulism, toxins are produced when food has not been processed or stored correctly. In this case, the microorganism produces structures called spores, which have high thermal resistance when processing is done poorly. Even if the bacteria are eliminated, the spores remain in the product which, when stored incorrectly and at an inadequate temperature, causes the spores to germinate, forming new cells.
The symptoms of botulism are the same as those of any food poisoning: nausea, vomiting, abdominal pain and diarrhea. They can appear between 12 and 36 hours after ingesting food with the toxin. Then, neurological symptoms appear, which are mainly double or blurred vision, drooping eyelids, difficulty swallowing and speaking, dry mouth, fatigue and lack of motor coordination. For this reason, diagnosis is very difficult.
Mortality rate
Bernadete highlights that the mortality rate is between 5% and 10% of cases, according to the literature. “The characteristic of botulism is that it is a descending paralysis, which culminates in paralysis of the diaphragm, with consequent respiratory impediment, which can lead to death.” Treatment must be carried out as quickly as possible to contain the progression of the disease. The first step is to wash the stomach or enema, which is the introduction of water into the anus, followed by intravenous administration of botulinum antitoxin, generally polyvalent. This must happen as soon as possible, because if the toxin is already inside the person’s nerve cells, the antitoxin cannot act. If necessary, respiratory support is applied. The recovery of those with botulism is very slow, it can take many months and can leave consequences such as tiredness and respiratory weakness, which may require continued therapy for years.
Industrialized foods, when processed correctly, do not carry risks. There are internationally accepted standards to be strictly followed. These standards establish the temperature and processing time, as well as the physical-chemical characteristics that the final product must have, such as acidity, the amount of water that prevents the germination of spores possibly present and, consequently, the production of toxins. Depending on the food, refrigeration is also important.
Homemade preserves and other similar products, prepared by people who are unaware of the precautions needed to prevent the problem, are among the biggest risks. Even if the food has no change in appearance or sensory characteristics, such as odor or color, it may contain the toxin. For this reason, it is recommended that any suspected food be boiled or heated to at least 80 degrees for at least 10 minutes.
In any case, botulism is a very rare disease and its numbers are very low in Brazil and around the world. The most recent epidemiological bulletin published by the Health and Environment Surveillance Secretariat of the Ministry of Health, from 2006 to the beginning of 2020, accounts for 413 suspected cases of botulism reported in the country. Of this total, approximately 3% were duplicates, that is, there are about 400 valid records. Many may remember the use of botulinum toxin by aesthetic clinics on different parts of the human body; initially there is no risk because the quantities are very small, but when the procedure is not done correctly, botulism can occur.