H.—3l.

The measures taken by the Department to prevent the spread of the disease were as follows : — (1) As soon as it became obvious that poliomyelitis in epidemic form was present in Dunedin, the public were notified of this fact. They were instructed as to the. importance of obscure febrile attacks amongst children, and were advised in all such cases to seek medical advice. (2) The medical profession were given early information as to the position. A memorandum which had been issued in connection with the epidemic of 1924-25 over the joint signatures of the then President of the New Zealand Branch of the British Medical Association and the Director-General of Health was brought up to date and a copy forwarded to every medical practitioner on the register. Such information as was available in regard to the use of nasal sprays. and Serum was also placed before the profession. (3) The public were urged to keep children away from places of entertainment, and from public gatherings such as pictures, &c. The picture-theatre proprietors co-operated in a most generous way, and voluntarily agreed to the exclusion of children from picture-theatres throughout the whole of New Zealand. (4) Schools throughout the whole of New Zealand were closed as soon as it was obvious that the disease was present in Dunedin in epidemic form. (5) An early opportunity was taken to meet representatives of the New Zealand Branch of the British Medical Association, and to invite suggestions for the control of the epidemic. One valuable suggestion which was adopted was the appointment in each of the four main centres of medical practitioners with special knowledge of poliomyelitis and its treatment, who would be available for consultation with any general practitioner who wished their advice. (6) Cases with few exceptions were admitted to hospital. (7) In the early stages of the epidemic the incubation and isolation periods which were adopted were respectively fourteen days and six weeks. After some time these were reduced to ten days and four weeks, the principal reason being that Dunedin Hospital was becoming overcrowded with many mild and abortive cases which rapidly recovered and were free from clinical signs after a few days. (8) Just before Christmas, when there was still considerable doubt as to the possible force of the epidemic, much prominence was given to the fact that cases were occurring in other parts of New Zealand which had close connection with Dunedin. In order to limit as far as possible the movements of people from Dunedin during the holiday season, restrictions were placed upon the exodus of children from Dunedin. The restrictions were not absolute, as in a limited number of cases, where there was no contact with known cases of poliomyelitis and the prospective travellers could show good and sufficient reason for wishing to leave Dunedin, permission was given them to do so. The first cases reported were 2in Dunedin on the 4th December. No further cases were reported until the 11th, when 3 were notified. By the 14th 11 cases had occurred, and on that date the schools in Dunedin were closed. The following week new cases numbered 37 in Dunedin, 2in Southland, and 1 in the southern portion of the Canterbury District. This week marked the peak of the epidemic in Dunedin. It is interesting to note that, allowing an incubation period of seven days, the closing of the schools was apparently associated with the decline in incidence. There is no doubt that parents accepted the advice of the Department and isolated their children as far as possible from outside contact. The epidemic showed no tendency to increase until March, and, with the exception of a comparatively few cases in other district in New Zealand, was confined to Otago and the two contiguous districts. Its progress in Otago and Southland is described by the Medical Officer of Health as follows : — "A case which had its onset on 26th November, 1936, was notified from North-East Valley, Dunedin, on 4th December by a private practitioner, a second with onset also on 26th November was notified the same day from South Dunedin by the Dunedin Hospital, both mild in type. There was then a clear interval of seven days. On the 11th, 3 cases were notified as admitted to the Dunedin Hospital. Two of these, girls of fourteen and fifteen years respectively, showed definite paralysis. It was then apparent that an epidemic was beginning in Dunedin, of what magnitude no one could say, and measures to be described later were taken to control it. " It is now clear in the light of house-to-house inquiries that from 13th November, 1936, onwards cases were occurring in Dunedin and its suburbs. " The first traceable paralysed case occurred in Green Island, near Dunedin, the onset of symptoms being on 13th November, 1936. " By sth December cases presenting at least systemic symptoms of poliomyelitis, but not notified, had occurred in Caversham, South Dunedin, St. Kilda, Musselburgh, Mornington, towards the centre of the city in King Street and from North-East Valley. "By 11th December, 5 statutory notifications of poliomyelitis, all from Dunedin and suburbs, had been received. Two of these, notified on Friday, the 11th, showed definite paralysis. On that day all medical practitioners in Otago and Southland were advised by circular regarding the epidemic and the precautionary measures recommended by the Ministry of Health of England. On Monday, 14th December, all schools were closed, other precautionary measures taken, and the public generally advised.

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