Staphylococcal Food Poisoning Associated with Spray-Dried Milk

Abstract

SummaryEight explosive outbreaks of food poisoning, occurring in school canteens in England during 1953 and affecting 1190 known cases, are described. The clinical features were characteristic of the toxin type of illness. No deaths occurred.The food causing all of these outbreaks was prepared from spray-dried skim milk powder. It was not subsequently heat-treated and was usually consumed 3–4 hr. after preparation.The spray-dried milk powder proved to contain a high content of bacteria, including large numbers of Staph. aureus, of a phage pattern often associated with food poisoning. The assumption was therefore made that these outbreaks were caused by staphylococcal enterotoxin.Because the food was often consumed within 3–4 hr. of reconstitution of the milk powder—before, in fact, the staphylococci had had time to grow—it is concluded that the poisoning must have been due mainly to pre-formed toxin.Consideration is given to the opportunities for the formation of toxin in a spray-drying plant, and reasons are brought forward for believing that it is formed mainly in the balance tank where the warm milk is kept, sometimes for several hours, before passing into the final drying chamber.The processing of the milk and the precautions for preventing contamination of the finished product are discussed.

Chemical and Microbiological Evaluation of Pasteurized Milk Available in Sylhet City of Bangladesh

“…The reason for high bacterial count in the pasteurized milks might include defective pasteurization machinery, surviving pasteurization, and post-pasteurized contamination due to poor processing and handling conditions and/or poor hygienic practices by the concerned employees. Anderson and Stone (1955) also remarked that pasteurized milk might be contaminated due to poor bacteriological quality of milk and inadequate plant cleanliness.…”

Communicable disease associated with milk and dairy products in England and Wales 1951-80.

“…One outbreak due to sheep cheese caused by B melitensis type 2 affected seven people after eating Italian Pecorino cheese made from unpasteurised milk,4' and one due to goat cheese caused by S typhimurium affected six students who developed diarrhoea and vomiting [12][13][14][15][16][17][18] hours after eating Turkish goat cheese in brine.…”

Recherche de staphylocoques pathogènes dans du lait en poudre

“…Le rôle du lait en poudre comme agent transporteur de staphylocoques et leurs toxines fut exposé par Anderson et Stone [1] et Armijo et al [2], et depuis lors on a diagnostiqué des foyers toxiques dus à ce type de germes et dont l'origine fut la consommation de lait en poudre dans divers pays.…”