Staphylococcal food poisoning in the United Kingdom, 1969–90

TLDR

The PHLS Food Hygiene Laboratory examined 359 Staphylococcus aureus strains from UK outbreaks (1969–1990) for enterotoxin production and tested implicated foods for toxin presence. Seventy‑nine percent of the isolates produced enterotoxin A (alone or with others), with bacterial loads ranging from undetectable to 1.5 × 10¹⁰ cfu/g (median 3.0 × 10⁷ cfu/g); toxin was found without viable bacteria in two cheese outbreaks, meat/poultry accounted for 75% of cases (ham and chicken most common), fish/shellfish 7%, milk 8%, contamination mainly occurred at home, and 71% of strains were lysed by group III or I/III phages.

Abstract

Between 1969 and 1990 strains of Staphylococcus aureus from 359 outbreaks and sporadic cases of staphylococcal food poisoning in the United Kingdom were examined in the PHLS Food Hygiene Laboratory for the production of enterotoxin. In a number of instances the incriminated foods were also examined for the presence of enterotoxin. Strains from 79% of incidents produced enterotoxin A alone or together with another enterotoxin. The level of S. aureus present in the foods ranged from no viable S. aureus detected to 1.5 x 10(10) c.f.u./g with a median of 3.0 x 10(7) c.f.u./g. Enterotoxin was detected in foods in the absence of viable S. aureus in only two outbreaks and in both cheese was the implicated food. Meat, poultry or their products were the vehicle in 75% of incidents with ham and chicken most frequently implicated. Other foods included fish and shellfish (7%) and milk and milk products (8%). Most contamination took place in the home followed by restaurants and shops. Seventy-one percent of the incident strains were lysed by phages of group III or I/III.