A form of paralytic disease showing out in the form of food poisoning is Botulism. It is caused by Clostridium botulinum. The bacterium as such is noninvasive and noninfectious. It produces heat resistant spores which can withstand 100oC. They produce a powerful exotoxin which is a neurotoxin and causes slow death. Only a tiny amount of it can cause death. A saprophyte seen in virgin soil, vegetables, hay, animal manure, sea mud, etc. is a strict anaerobe. Seven types of this organism has been designated: Type A, B, C, D, E, F, G.
In certain foods, the bacterial growth can cause foul, rotten smell. Protein containing material such as meat, low-acid vegetables, etc. creates an unbearable odor on infestation. High-acid foods do not have any characteristic odor, but gets toxified. Gas production cannot be visualized in every spoiled food.
Three types of Botulism are being identified: food borne, wound borne and infant botulism. General symptoms include nausea, diarrhoea, exhaustion, dizziness and headache.
Food borne is due to the ingestion of preformed toxin. Preserved foods such as meat, canned vegetables and fish are the sources of infection. The cans containing foods which are spoiled by the bacteria seem to be puffed up and bubbling occurs during opening.
Symptoms start to appear about 12-36 hours after ingestion of the spoiled food. Double vision, dryness of mouth, swollen and coated tongue, vomiting, thirst, constipation, swallowing, breathing and speaking difficulty are commonly seen among infected people. Involuntary muscles become paralyzed and even death can occur due to respiratory failure.
Wound borne botulism are very rarely seen. Toxins are produced at the site of infection and it is absorbed from the there. Symptoms seem to be similar to the food borne type, but gastrointestinal problems will be absent.
Infant botulism is a toxico-infection. The toxin is produced inside the gut of the humans when the spores are ingested along with food and get established there. The bacterium as different from the other cases starts to grow inside the gut of the infant. Infants below 6 months are usually seen to be infected with infant botulism. The normally appearing symptoms are constipation, poor feeding, diminished reflex, be deficient in sucking, tiredness, general weakness, loss of head control, distorted crying and droopiness. Toxin is being excreted through feces. Infant death can also occur if not treated appropriately.
Control of botulism can be obtained by properly canning the food items or preserving them properly. Immunization is found to be effective. Two injections of aluminium sulphate adsorbed toxoid may be given at 10 weeks interval, followed by a booster dose a year later. The most successful treatment for botulism is the administration of the antitoxin. But it may be useful only if given in the earlier stages. The fluid balance maintenance and simulated respiration are also done as treatment.
Among the home-canned foods, sweet corn, spinach, asparagus, etc. is responsible for botulism outbreaks. Clostridium botulinum can remain alive for long periods in foods such as raw and pre cooked frozen foods. The toxin can be inactivated if the toxin is properly heated. Prevent the ingestion of toxin containing food can also help to prevent the infection.
