Food poisoning from the contamination of food with the paratyphoid-enteritidis group of bacteria is no doubt more prevalent than available statistics indicate. Most authorities agree that its clinical manifestations, namely, incubation period of several hours, abdominal pain, nausea, vomiting and diarrhea and sometimes fever, are those of an intoxication. The demonstration in the laboratory of a toxin or poison in the causative food, however, is apparently associated with technical difficulties. Even the production of experimental food poisoning with filtrates of known contaminated foods is unusually rare.1 The explanation of the mechanism of the production of this type of poisoning from food has long been sought.
In many instances in alleged outbreaks no organism, toxin or poison can be demonstrated, nor can the absence of an infection following the ingestion of contaminated food be fully explained, at least when some strains of B. paratyphosus A and B are concerned and