Botulism clinical forms

Worldwide, sporadic cases and hmited outbreaks of botulism can occur when food and food products are prepared or preserved by improper methods that do not destroy the spores of Clostridium botulinum and permit the formation of botulinum toxin. In industrially developed countries, the case fatality rate of food-borne botulism is 5-10%. Person-to-person transmission of botulism is not known. Botulinum toxin is the most poisonous substance known and poses a major bioweapon threat. In addition to the clinical forms of natural botulism (food-borne, wound, and intestinal), there is a fourth, man-made form of inhalational botulism that results from aerosolized botulinum toxin. 

Other clinical forms of the disease share many of these signs and symptoms. The presentation and dma-tion of the disease are coupled to the relative persistence of the toxin in blocking the release of ACh at peripheral nerve synapses. Although untreated botulism is potentially deadly, the availability of antisemm has dramatically reduced the mortality rates for the common clinical manifestations of the disease. Severe cases of foodbome botulism may still require ventilatory support for over a month, and neurological symptoms can sometimes persist for more than a year (Mackle et al., 2001). 

Inhalational botulism cannot be clinically differentiated from the 3 naturally occurring forms... 

Although infant botulism was not recognized until a large outbreak occurred in Califomia in 1976 (Pickett et ah, 1976), it is currently the most prevalent form of botulism in the United States, accounting for approximately 70% of all cases (Shapiro et al., 1998). Because infant botulism results from a continual production of BoNT, it appears to be more effectively treated by antitoxin than is foodborne botulism. In a recently concluded 5 year randomized clinical trial carried out with a human botulinum immune globulin (BIG-IV), it was found that administration of BIG-IV within 3 days of hospitalization resulted in a 3 week reduction in the mean hospital stay, as well as substantial reductions in the time needed for intensive care and mechanical ventilation (Amon et al., 2006). In a nationwide open label study, BlG-lV was found to be effective even when administered 4—7 days after hospital admission, although to a somewhat lesser extent than when infusion was initiated at 3 days (Arnon et al., 2006). 

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