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The Liquid Egg (Pasteurization) Regulations, 1963
There are no egg pasteurization plants in Westminster, and any liquid egg used at premises in
the City would be subject to supervision by the local authority at the place of manufacture or,
examined on import.
Food Poisoning
During the year, information was received of some 419 persons stated to be suffering from food
poisoning. Not all were notified as such; in fact most of the incidents which come to the notice
of the Health Department are never officially notified by a medial practitioner—many who suffer
food poisoning experience only minor symptoms and therefore do not seek medical advice.
There are few aspects of food control work more satisfying than being able, often only after
exhaustive enquiries, to determine the causal agent, establish the vehicle of infection, and trace
the original source, so enabling the right advice to be given and appropriate steps taken to eliminate
the reservoir of infection. That this is possible only in comparatively few of the outbreaks
investigated is largely due to delay in informing the local Health Department of occurrences.
The requirement under Regulation 11 of the Food Hygiene (General) Regulations, 1960 to
notify the Medical Officer of certain specific infections in food handlers is quite unrealistic as the
dangers to the community are not so much from the patient who has been diagnosed as suffering
from, say, enteric fever, salmonellosis or staphylococcal infection, as from the person with
diarrhoea or a septic sore or boil who continues working among food. The Regulations appear to
need some amendment to require these additional conditions to be notified.
A summary of food poisoning investigations made during the year is given in Table 27, page 77
and the following is a resume of incidents involving two or more persons.
Five children, three of one family and two of another, were found to be positive for Salmonella
Stanley. All had consumed a dish of sweet and sour pork. Several others had consumed this dish
but were unaffected. Enquiry revealed other outbreaks of food poisoning in the Greater London
Area and southern parts of England where the causative organism had been identified as Salmonella
Stanley, all of the same phage type. The occurrences indicated an association with the consumption
of pig meat obtained from a particular firm, and the pattern of the outbreak had reflected the distribution
system of this firm. The matter was dealt with by the local authority concerned.
Two outbreaks affecting 170 persons occurred following two separate functions. Salmonella
typhimurium organisms, phage type 14, were isolated both from stool specimens and from mayonnaise
consumed which was prepared by the firm (whose premises were outside Westminster) who
carried out the "outside catering" arrangements for both functions. Phage type 14 is most frequently
associated with poultry and it seemed probable that the organism was introduced into the mayonnaise
in infected egg yolk, although there was no conclusive evidence to confirm this. A third incident
(not in Westminster) involved a party of some 60 persons who consumed mayonnaise supplied
by the same firm. The phage type isolated was identical. The matter was dealt with by the local
authority concerned.
Seventy persons suffered abdominal pain and diarrhoea, some quite severely, following a banquet
at a local restaurant. Information concerning the outbreak was not received in this Department
until ten days after the occurrence, when specimens of food consumed were no longer available.
Faecal specimens of 12 persons affected were negative. Investigation at the restaurant showed
environmental hygiene in the kitchen and ancillary rooms and the personal hygiene of the food
handlers were satisfactory.
An outbreak of Salmonella typhimurium infection occurred at a large general hospital in the City.
The episode extended over a period of two months, involving 37 patients (27 clinical cases and
10 symptomless excretors), and eight nurses (of whom all but one were symptomless excretors),
spread over nine wards and a premature baby unit. The affected wards were closed and bacteriological
screening of all patients and staff throughout the entire hospital was carried out. All the main
kitchen staff were found to be free from infection.
It was not possible to pinpoint the original source of infection, although it may well have been
an elderly man who was admitted, faecally incontinent, to the first ward known to have been
infected. Cross-infection clearly played a prominent part, although very often it was by no means
clear how this had been effected. Of special interest in this regard was the isolation of the responsible
organism from the dust of the vacuum cleaner in use, as well as from the nose and throat of one
of the patients affected, on the last ward to be involved in the outbreak. The affected wards were not
reopened until they had been disinfected and all remaining patients found to be free from infection.