View report page

4
Food Poisoning.
Only one formal notification of a case of food-poisoning was received during the year but
five outbreaks of mild food-poisoning were reported and were investigated. The incidents were
all reported to the Public Health Committee at the time of their occurrence. The reports are
repeated here in order that they may be readily available for reference at any time in the future.
Incident No. 1.
On Tuesday, 8th March, I was informed that a number of cases of illness had occurred
amongst the staff of a firm in the City, and it appeared that the cause was a luncheon meal eaten
in a canteen the previous day.
On enquiry it was ascertained that 36 persons were affected. The symptoms were abdominal
pain and diarrhoea, with vomiting in six cases. The average period between the eating of the
meal and the onset of symptoms was 12 hours, and the average duration of symptoms was
14 hours.
The luncheon menu on Monday, 7th March, comprised a variety of dishes, but the only one
eaten by all those who developed symptoms was Beef and Tongue Patty. None of the actual
patty was available for examination, nor was there any residue of the beef from which it was
made. There still remained some of the tongue and this was submitted for bacteriological
examination.
The beef in the patty was from either 53 lbs. delivered on Thursday, 3rd March, or a similar
quantity delivered on 4th March, or perhaps from both. The beef was in each case cooked on the
day of delivery and stored in a refrigerator and served on Friday, 4th March, and Monday, 7th
March.
The tongue was from a tin opened for a special meal on Tuesday, 1st March, and not all
used on that occasion. It had been kept in a refrigerator in the meantime.
The Bacteriologist reported on his examination of all the five items from the luncheon menu
which were available and submitted to him. These were, parsley butter, tomato juice, custard
powder, grape fruit juice and tongue. No pathogenic organisms nor any abnormal number of
non-pathogenic organisms were found in any of the samples. The bacteriologist's conclusion
was:—"Nothing has been found in any of the materials which would account for symptoms of
food poisoning."
"It is possible that the beef used in making the beef and tongue patty was at fault, or that
some change took place in this dish after it was made up."
All except one of the persons affected had returned to work by Wednesday morning, 9th
March. The exception was a boy of 16 who lives in Islington and who was notified as a case of
food poisoning by his doctor. The Medical Officer of Health of Islington kindly arranged for the
bacteriological examination of a sample of faeces from this case, but no pathogenic organisms were
isolated.
A thorough inspection was made of the kitchen of the restaurant, which was being used as
a canteen for the employees of this particular firm.
A number of unsatisfactory conditions were discovered. The restaurant has just changed
hands and the new owners have undertaken to remedy the defects. The opportunity was also
taken to instruct the staff in the importance of hygiene in the storage and preparation of food,
and in their individual responsibility in this respect.
Though, as so often happens, we were not able to identify with certainty the particular food
responsible because none remained by the time we became aware of the outbreak, there can be
little doubt that the beef and tongue patty was at fault.
Incident No. 2.
On 20th April I received a message that a number of people had been taken ill after a meal
at a staff canteen on 19th April.
On enquiry, it was ascertained that of 80 persons who took lunch in the canteen, 25 had
subsequently been ill.
The symptoms were abdominal pain and diarrhoea, without nausea or vomiting, coming on
ten to fifteen hours after the suspected meal, which comprised roast beef and Yorkshire pudding,
or stewed steak, or cold ham; boiled or baked potatoes; tinned peas or cabbage, gravy made with
Oxo; bread and butter pudding, or jelly and custard.
It appeared that the roast beef or the gravy was the article of diet responsible for the illness.
The beef, a chuck-roast weighing 14 lbs., was cooked on 18th April, kept overnight in a refrigerator,
and reheated and served on 19th April.
Some beef and gravy was still available and was sent to the City Bacteriologist for
examination.
Five persons were still away from work. Their addresses were obtained, and the medical
officers of health of the districts in which they lived were communicated with by telephone and
asked to have samples of faces examined. All the medical officers readily consented to co-operate
in the investigation.
The City Bacteriologist reported that films and cultures from the gravy showed no bacteria,
but the beef showed numerous Clostridia in films, and in anærobic plate cultures a profuse growth
of three types of Clostridia, one of which formed a spreading growth obscuring the others. This
latter type appeared to be Clostridium welchii and included a few haemolytic and many nonhæmolytic
colonies.