Botulism: How does it manifest itself and why does it arise?

Botulism is a disease caused by the toxin botulinum toxin. Botulinum toxin is one of the strongest toxins in the world. It consists of gram-positive anaerobic bacteria (they do not need oxygen for their life) from the genus Clostridium.

We know several species of bacteria, the best known are probably Clostridium botulinum and others such as Clostridia butyricum or Clostridia barati.

Otherwise, this disease is also called food poisoning, botulinum toxin poisoning, sausage poison poisoning or food botulism. Intoxication occurs by ingestion of poison. This poison has a neurotoxic effect, which means that it acts on the nervous system.

From history

This disease is not modern. The possible occurrence of the disease dates back to the years around 886 - 911, when the Byzantine emperor banned the production of blood vessels. Later in the 19th century, it was mentioned by the physician Justinus Kerner. The toxin-producing bacterium, Clostridia botulinum, was isolated by Emile van Ermeng in 1895, after mass poisoning caused by the consumption of smoked ham.

Food, bacteria, poison and poisoning

Intoxication, ie poisoning, is caused by foods in which  bacteria multiply. Especially for the wrong production or storage process. These foods include those that are high in protein in the first place. It is mainly meat, fish. From vegetables legumes, but also various fruits and mushrooms.

Foods high in protein are particularly risky, but also other, especially domestic products: 

• canned food (pâtés, lecho, cabbage)
• homemade products and jams, such as sausages, bacon, ham, peas, beans, cabbage, corn, pickled nuts, garlic, onions
• meat, especially sausages such as sausage, ham, stuffing
• soft cheeses, cheese sauce or yoghurts
• fish (fish salad, at)
• mushrooms, mainly wrapped in foil
• vegetables, in particular legumes
• various fruits (strawberry compote and others)

In the case of cans or jams, it is necessary to pay attention to whether they do not have a hollow lid. This can indicate their deterioration, and thus the presence of harmful substances such as fungi but also bacteria. Fungi of these foods can also cause other diseases and liver damage.

Botulinum toxin, also referred to as BoNT or BTX, can cause death by ingestion of 30 ng.

The name botulism is derived from the Latin term botulus , which is sausage. The term intoxication as sausage poison poisoning is also known. Clostridium botulinum can exist in two forms, an active as well as an inactive form.

The table lists the forms in which clostridia may occur

The bacteria multiply under suitable conditions. In case of lack of oxygen. These subsequently produce botulinum toxin. Durable spores can withstand even longer boiling at 100 ° C. However, the toxin itself is thermolabile, i.e. it is destroyed by heat. The toxin inactivates heating at 80 ° C for 10 minutes.

The toxin passes through the gastric acid environment without problems.

Bacteria do not multiply in an acidic environment, at pH less than 4.5 (some fruits)

7 immunologically distinct types of botulinum toxins are known. And these are types A, B, C, D, E, F, G, while types C and D are only avian pathogens. The neurotoxin is made up of two chains. These chains are quite unstable. They are disturbed by heat, but also by high pH. After disruption of the chain, their biological activity is canceled and they are no longer toxic.

The cause of botulism is therefore the ingestion of clostidia bacteria, their spores and toxins, i.e. botulinum toxins. This form is called alimentary botulism. The term food, ie related to food and its ingestion, ie poisoning after eating. In addition to this species, there are others.

Botulinum toxin can enter the body in various ways, then it is labeled accordingly, namely:

• food botulism, ie after eating
• intestinal when bacteria multiply in the gut, where they also produce toxins
• by inhalation, if inhaled
• wound when the entrance gate is injured skin
• iatrogenic, when administered by injection

Alimentary botulism is actually food poisoning that contains a toxin. Bacteria multiply in a risky food, such as a poorly made can. They then produce BTX. In doing so, conditions such as:

• the food contains botulinum toxin
• the spores were not destroyed during food processing
• spores formed during food storage
• botulinum toxin is not destroyed before eating

The intestinal form of botulism occurs mainly in infants. It is also referred to as infant botulism, ie infant botulism. Rarity is occurrence in adults. It is also referred to as adult intestinal botulism. The cause is mainly the consumption of honey. Therefore, it is not recommended to give honey to children under one year of age.

Inhaled and wounded forms of botulism are less common. When inhaled, spores are inhaled and in the case of wounds, the wound is infected with Clostridial bacteria. The wound form is more common in drug addicts. Iatrogenic botulism can occur as a complication of a therapeutically administered botox.

Between 1991 and 2015, 45 cases of botulism after food ingestion were reported in Slovakia.
Of these, 18 cases were related to the consumption of homemade pate.
2 events of intoxication occurred after consuming pate from the store.

Clostridia are found all over the world. Especially in soil, but also in water and sediments at the bottom of seas or rivers. These bacteria have been proven in plants as well as in the intestines of wild and domestic animals. Fertilizers or sewage pollution contribute to contamination, ie soil contamination.

Botulinum toxin is misused for the production of biological weapons, however, it also has therapeutic uses in medicine.

As mentioned above, clostridia can be found in a variety of foods. Especially if the correct production procedure has not been followed. In industrial production, the food industry, the risk is low. However, this increases in the case of domestic production, when it is higher.

It is very important to be careful. If the can or jam is bloated, bulged, if the cap does not hold and insulates poorly. It is similar in the case of smoked meats (especially sausages or bacon), homemade sausage. Home-made jams of vegetables or fruits. Similarly with canned fish or smoked fish.

The spores can also withstand cooking at 100 ° C for several hours but are sensitive at a steam temperature of 120 ° C for 30 minutes. Botulinum toxin itself is sensitive and is destroyed by the boiling point in a matter of seconds. We run the risk of not following the principles of production or heat treatment of food before consumption.

How does the toxin work?

After entering the body, botulinum toxin is transmitted from the digestive tract through the blood or lymph. Botulinum toxin is a neurotoxin . The term neurotoxin refers to the action  on the nervous system. It causes  paralysis of the peripheral nervous system by inhibiting the release of acetylcholine. In addition, it reduces the production of other neurotransmitters such as norepinephrine, serotonin or dopamine. 

BTX blocks nerve fiber function, leading to muscle paralysis. The toxin blocks synaptic transmission, both on the neuromuscular plaque and at the nerve endings. Thus, there is a disturbance of the conduction conduction. As a result, muscle paralysis occurs. Paralysis of the respiratory muscles and subsequent suffocation is dangerous.

In food botulism, i.e. after ingestion, the incubation period is usually 12-72 hours. However, in some severe cases, symptoms may occur after 2 hours. In fact, it is reported that the symptoms of intoxication did not occur until 8 days later.

As botulinum toxin has a neurotoxic effect, it is manifested by damage to the nervous system. The onset of difficulty from the muscles of the head is reported to be gradually downwards. Thus, among the first symptoms is paralysis of the mimic muscles, dilation of the pupils of the eyes, and impaired adaptation to light.

It occurs ptosis, down eyelid. For the suspicion of botulism, a speech or swallowing disorder also makes suspicion. Later, skeletal muscle involvement occurs, which manifests itself as paralysis. Paralysis can be partial, but also complete in severe cases. The severe form can also affect the respiratory muscles.

Respiratory failure, ie respiratory failure, is due not only to the paralysis of the respiratory muscles, but also to the possible inhalation of a foreign body or diet. A person suffocates and may die. That is why early diagnosis and treatment is very important.

Symptoms of botulism include:

• feeling sick (vomiting)
• swallowing disorder, i.e. dysphagia
• double vision (diplopia)
• dilation of the pupils, without reaction to light (photoreactions)
• dry mouth
• malaise, fatigue and exhaustion
• sweating
• muscle paralysis (from the head down)
  • ptosis, ie a decrease in eyelids
  • speech disorder
  • difficulty swallowing, risk of aspiration, ie inhalation
  • muscle weakness
  • skeletal paralysis, limb weakness to paralysis
  • respiratory muscle to respiratory failure
  • heart failure
• hoarse voice
• low blood pressure
• dizziness
• headache
• stomach ache
• urinary retention
• diarrhea or constipation

Although the nerves are affected, there is no disturbance of sensitivity, not even a disturbance of consciousness. The disease takes place in full consciousness. The cause is a disorder of nerve muscle transmission, conduction of nerve impulses. The most feared and serious complication is the cessation of heart activity and breathing. This is also the reason for early detection and treatment of the disease.

The clinical picture is important in the diagnosis and detection of the disease, taking a human history. The consumption of risky foods is also important. Of course, other examinations are subsequently performed, the task of which is to distinguish it from another disease (neurological, such as myasthenia gravis, but also encephalitis or vascular accident), ie differential diagnosis.

Detection of the toxin in serum, faeces or food residues is performed. A biological test in mice may be helpful. The botulinum toxin subtype can also be detected. Another method is to cultivate a biological sample (from blood, vomit, feces) or even from a food sample. EMG, which is an examination of the electrical activity of muscles, can be supplemented.

The incubation period of the disease is usually 12 - 72 hours. But it can also be significantly shorter or longer. The incubation period is the time from the ingress of the toxin to the first signs of intoxication. The first are weakness, malaise, fatigue and exhaustion. Sweating or dry mouth, but also general dryness of the mucous membranes.

Digestive problems are also among the first symptoms. Like a feeling of heaviness, nausea and vomiting and also abdominal pain. They may be accompanied by diarrhea or even severe constipation. A symptom, however, of a later stage is the cessation of urination, i.e. urinary retention.

Subsequently and between early manifestations, head muscle involvement occurs. The first is the mimic muscles, eyelids, which cause narrowing and lowering of the eyelids (ptosis). Double vision and dilation of the pupils are typical. The pupils are not capable of accommodation, ie adaptation to light conditions.

Throughout the disease, the person has fully preserved sensitivity and consciousness.

At a later stage , symptoms such as swallowing and speech disorders occur. Muscle paralysis progresses to the muscles of the neck, upper limbs and lower. The affected person has low blood pressure. A serious complication is respiratory muscle damage, respiratory failure and cardiac arrest, ie death.

Childhood form of botulism is rare. However, it most often occurs in the period from the 2nd to the 8th month. The child eats spores, which then produce toxins in the intestine. It is stated that it is most often after consuming infected honey, maple syrup, but also after eating the soil. Therefore, it is not recommended to give honey to children under 1 year.

In such a small child it is possible to observe difficulties such as:

• slow drinking milk, water
• changed voice when crying
• constipation
• reduced muscle tension

How the disease progresses and, of course, the speed of progression depends on the dose of the toxin. It also affects the overall condition of the body. Last but not least, rapid diagnosis and treatment is important.

Prevention is important

Prevention is particularly important in the fight against botulism. This is in the form of compliance with the principles of processing and production of risky foods. Of course, not only in the food industry, but also in households. An example is the observance of personal hygiene when handling food.

Food should be thoroughly cleaned. Such as root vegetables. It is also important to clean food before canning itself. The correct temperature and time must be maintained during sterilization. If the can or jam is swollen, it is hollow and must be ruled out.

Botulism is rare worldwide, but especially in family epidemics for breaches of the principles.

Subsequent heat treatment of canned food after opening and before consumption is also suitable. Heat treatment destroys sensitive toxins. Equally important is the temperature when storing food , especially during the minimum shelf life. An example is the storage of some foods at a temperature below 4 ° C.

However, secondary contamination can also occur during food processing. This means that Clostridial bacteria are introduced into foods in which they are not normally found. If food contamination is suspected, it is important to examine the food. With a positive result, their withdrawal from sale. the occurrence of the disease is subject to reporting.

Botox and its therapeutic use

Botulinum toxin is the most effective poison in the world. And yet it has found use in medicine as a therapeutic agent. Botox, as it is called, has uses in more than 250 indication cases. It is used by medicine as well as aesthetic medicine. Of course, a thousand times lower and safe dose is used, which could cause unwanted difficulties.

In the 1970s, Alan B. Scott was the first to use botox in the treatment of strabismus.

Use of botox for its positive therapeutic effects, for example in cases of:

• in neurology
  • muscle spasticity, ie muscle stiffness
  • muscular dystonia, convulsions
  • tension headache
  • migraine
  • Parkinson's disease
  • Cerebral palsy
• hyperhidrosis, which is excessive sweating
• urinary incontinence
• anal fissure
• vaginismus, or painful contraction of the vagina
• aesthetic medicine and pelvic floor muscles
  • search for mimic (facial) wrinkles