Bacterial contamination of hospital food with special reference toClostridium welchiifood poisoning

Abstract

1. An examination of eighty-nine samples of uncooked and thirty-eight samples of cooked food purchased by one particular hospital showed that the purchased food was bacteriologically clean.2. A similar examination of 173 samples of food after it was cooked and prepared for serving in the hospital kitchens showed that, with the exception of cold chicken, the bacterial flora was greatly reduced by cooking. Ten of forty-six samples of cold chicken, however, were contaminated with fairly large numbers ofCl. welchii.3. An investigation into the cooking and handling of the fowls indicated that contamination of the cooked fowls with kitchen dust was a probable explanation for the presence ofCl. welchii.4. Immediate refrigeration of the fowls, well separated on shallow trays, was shown to be a satisfactory method of preventing the growth of contaminatingCl. welchiito any dangerous extent.5. Six outbreaks of food poisoning, in which there was an association between cold chicken and the clinical symptoms ofCl. welchiifood poisoning, are reported and discussed.I have pleasure in thanking Dr Betty Hobbs of the Food Hygiene Laboratory of the Public Health Laboratory Service at Colindale for the serological typing of numerous strains ofCl. welchii; Mr D. B. Colquhoun for assistance with the phage-typing of the staphylococci; Mr G. Kerr for the photography; and the kitchen staff in the hospital concerned for making possible the numerous samplings of food and the other inquiries into the day-to-day affairs of the hospital catering department.

Distribution of heat-resistant Clostridium welchii in a rural area of Australia

“…but then cools more slowly, remaining within the temperature range of 20-50°C. for many hours (McKillop, 1959). This is particularly so in a warm kitchen, where several roasts are allowed to stand together after cooking.…”

STUDIES ON THE GROWTH, SPORULATION AND CARRIAGE OF CLOSTRIDIUM WELCHII WITH SPECIAL REFERENCE TO FOOD POISONING STRAINS

“…Moreover, institutional meals may maintain unduly high populations of C1. welchii (Hobbs et al 1963;McKillop, 1959). Different methods of sampling and treating faeces may account for some of the variations in these figures, but the methods used by Leeming and his colleagues were those currently accepted and involved heating faeces in cooked meat broth for 1 hr a t 100"; contamination of the specimen from the bedpan was avoided (Leeming, pers.…”

Clostridium perfringens in Bovine Liversa

“…The plates were incubated for 43 hr at 37°C in an atmosphere of 90% nitrogen and log/O carbon dioxide. Typical colonies appearing on the medium were transferred to C. perfringcrrs identification media (Strong et al, 1963). Those cultures possessing the characteristics established for C. perf&gens were "typed" according to toxin production.…”