Clostridium Botulinum

Since i was on the topic of bacteria agents of foodborne illness, i'm highly inspired to write about one of my favourite bacteria: Clostridium botulinium :)

Well, Clostridium botulinium cells are Gram-positive, motile, obligately anaerobic, straight or slightly curved rods that form spores. There are several strains of C.botulinium but the common feature of all is that they produce pharmacologically similar neurotoxins responsible for BOTULISM.

So what is botulism? It is an example of bacterial food poisoning that results from ingestion of an exotoxin produced by C.botulinium growing in the food. Toxins is absorbed in the upper part of the small intestine and reaches bloodstream via the lymphatics. It binds to the nerve ending at the nerve-muscle junction, blocking release of the acetylcholine responsible for transmission of stimuli, thus producing flaccid paralysis.

Initial symptoms occur commonly 12-48hr after consumption of the toxin containing food. Symptoms includes vomiting, constipation, urine retention, double vision, difficulty in swallowing, dry mouth and difficulty in speaking. The patient remains conscious until in fatal cases, shortly before the end when the progressive weakness results in heart/respiratory failure (usually 1-7 days after onset of symptoms).

C.botulinium in food is not dangerous unless it can develop into a toxin producing vegetative culture. Since C.botulinium is an anaerobe, presence of oxygen will inhibit its growth. However, if anaerobic conditions is present, example sauteed onions (the melted margarine formed a covering layer that prevented atmospheric oxygen from entering), toxins can form. Outbreaks of C.botulinium has been associated with home preserved mushrooms bottled in oil, ungutted salted whitefish, and even a stew containing roast beef and potatoes which was left on stove for 3 days with a heavy lid on and eaten without prior reheating. Eating cooked food left for a few days (eg baked frozen pot pie) without reheating can lead to botulism as well. In conclusion, ALWAYS reheat any food before consumption. Boiling for about 10 min before eating can destroy any toxin present. Try not to have cooked food held at temperatures (4C - 60C) for more than 4 hours as well.

Botulism is one of the more fatal food poisoning illness around but thankfully, it can be easily prevented if precaution is taken! :)

I shall bore you guys with more bacteria agents of foodborne illness next time round haha..