Botulism is a lethal disease caused by the toxin botulin that is produced by the bacterium clostridium botulinum. Lethal effect of the toxin is due to its action on the nervous system resulting in a respiratory and musculoskeletal paralysis.
The source of botulism infection can be from three different sources. The most commonly seen form is the food poisoning or the food borne botulism, which is caused due to consumption of food that contains the toxin. Wound botulism is caused due to the infection of the wounded area by the clostridium bacterium that releases the toxin. The last type is the infant botulism, as the name indicated it is caused due to ingestion of spores of the bacterium. These spores resist the action of the digestive enzymes and grow in the intestines resulting in the release of the toxin.
The paralytic action of the botulin toxin is due to its interference with an enzyme that plays role in the release of acetylcholine at the nerve junctions. This in turn initiates the paralytic effects characteristic of botulism. Despite of the lethal effects of the toxin, very minute amounts of the toxin are used to relieve wrinkles in the face. This is done by paralyzing the facial muscles. It is also used as a treatment to relieve chronic muscle spasms, in which the muscles are temporarily paralyzed to relieve the spasms.
Characteristic symptoms of botulism are observed within 12-36 hours of intake of the toxin. However, they can be manifested even after ten days or very early within first six hours. Characteristic symptoms of botulism include dry mouth, difficulty to breath, vomiting, severe diarrhea, slurred speech, weakness and vomiting. The extent of poisoning is very severe that it finally leads to muscle paralysis. If the paralytic effects are not taken care immediately, it may spread to trunk muscles, arms, legs and even up to the respiratory muscles leading to death.
The symptoms of infant botulism are not very severe. Symptoms include vomiting, light headedness and difficulty to feed. Infant botulism is mainly seen in infants as they do not have enough intestinal bacteria to combat harmful bacterial growth.
Diagnosis of the botulism is generally done with the symptoms reported by the patient. However, confirmatory tests have to be conducted to eliminate the chances of other disease such as myasthenia gravis with similar symptoms. Patients with botulism contain the toxin in the serum, the spinal fluid and even in the stools in case of infant botulism and food borne botulism. To rule out myasthenia gravis a nerve conduction test is conducted.
As the symptoms are very severe, the patient needs intensive medical care. In cases of respiratory failure, the patient is supported with ventilators for few weeks until the symptoms subside. If the diagnosis is done in the initial stages, an antitoxin is injected to counteract the action of the toxin. However, the patient needs intensive medical care to recover from the poisoning effects such as vomiting and other symptoms.
Though a very lethal disease, it can be very easily prevented by avoiding consumption of improperly canned foods. The bacteria cannot resist high temperatures. Hence, heating foods before consumption causes the lyses of the bacterium.