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plates, together with other meat (cold roast beef and ham) by a
Mrs. F. who lived within this Borough.
Staphylococcus aureus was isolated from a throat swab taken
from Mrs. F. and this was the same type as that isolated from the
tongue. A faecal specimen submitted by Mrs. B. to the Medical
Officer of Health of the area in which she lived proved negative.
Negative nose and throat swabs were obtained from other persons
who assisted at the reception.
It appears likely that the tongue was infected by Mrs. F. although
in the absence of nose and throat swabs from Mrs. B. this is not
certain.
The large outbreak of undiscovered cause occurred in a canteen
of a large block of offices, serving 1,000 lunches per day.
On the 6th October, 800 persons had a meal which included
steak and kidney pie with gravy. From 8 to 18 hours after, 310
became ill, the main symptoms being flatulence, colic and
diarrhoea. The illness was only moderately severe and lasted from
6 to 12 hours. No pathogens were isolated from faeces of cases or
food handlers.
In the provisional report of the Pathological Laboratory,
Clostridium Welchii was present in the specimens of food submitted,
but subsequently it was found not to be the heat-resistant strain,
it being killed at 80° in 10 minutes.
The Pathological Laboratory have stated that the particular strain
of Clostridium Welchii found was not a proven pathogen, and in
the absence of any other pathogenic organisms they must
provisionally conclude that the outbreak was toxic in origin,
probably staphylococcal, and that the organisms themselves were
killed in the re-heating, leaving the toxin intact.
After investigating the preparation of the meal, the manageress
was advised of the potential danger of cooking meat in large bulk,
leaving it in a warm kitchen overnight and re-heating the following
day.
Another factor investigated was the large number of house
sparrows which were living and Inesting within the restaurant.
Faecal specimens were obtained and submitted for examination, but
no pathogenic organisms were found. Subsequently various screening
measures to windows were carried out to prevent the ingress
of sparrows, and in addition the kitchen premises were redecorated.
The remaining outbreak was restricted to 6 members of one
household!. Faecal specimens obtained 3 days after onset were
negative, and all suspected food had been consumed before notifications
were received.