Staphylococcal Food Poisoning in the Manchester Area

Abstract

Outbreaks of staphylococcal food poisoning recorded in the Manchester area in the four years 1949-1952 are analysed. The majority were caused by prepared foods contaminated by manufacturers or caterers, and sixteen of the twenty were due to meat products. An unusual feature of the series is the occurrence of four outbreaks due to food from freshly-opened tins. The conditions under which the causative bacteria gained access to the various foods and multiplied in them are described.

The food handlers in the establishments involved in thirteen of the outbreaks were examined for the " epidemic type " of Staphylococcus aureus. It was isolated from the hands of one or more persons in twelve outbreaks, but most of the hand carriers did not have the same strain in their nose swabs. Persons working together tended to carry the same strain on their hands.

In the general population, hand carriage is unusual except in nose carriers, and the type present in the nose and on the hands is usually the same. The unusual findings in food handlers are probably due to the frequency with which they receive minor injuries to the hands and the ease with which hand-to-hand transfer of bacteria occurs under poor hygienic conditions.

It is almost impossible to prevent the contamination of many food products with S. aureus. Although it is desirable to minimize this contamination, the most reliable methods of preventing staphylococcal food poisoning are those designed to prevent the multiplication of the organism in food.