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REPORTS OF DIVISIONAL DIRECTORS DIVISION OF PUBLIC HYGIENE Infectious Diseases Diphtheria.—During 1947 there were 546 cases of diphtheria (Europeans, 506; Maoris, 40), compared with 1,683 cases in 1946. The distribution of cases shows the same trend as in recent previous years, in that the North Island, with two-thirds of the population, had eight-ninths of the cases. This fall in the incidence of diphtheria is world-wide and cannot be claimed as the result of the Department's campaign of inoculation, important though that is. Scarlet Fever.—Notifications totalled 871 (Europeans, 866 ; Maoris, 5), compared with 1,465, 5,081, and 7,622 in 1946, 1945, and 1944 respectively. This disease appears to run in regular cycles, with peaks of high incidence about every eight years. On Ist December, 1947, a Notifiable Infectious Diseases Order was promulgated making streptococcal sore throat (including scarlet fever) a notifiable infectious disease. For a number of years it has been recognized that during every outbreak of scarlet fever a number of cases of sore throat without rash occur and may give rise to further cases of typical scarlet fever. It seems unreasonable to ignore these cases and to impose restrictions only in those cases showing a rash. In future, appropriate action will be possible in any case where there is good reason to suppose that a streptococcal infection is involved. Enteric Fever. —There were 146 cases, compared with 98 cases in 1946, and for the first time for many years the European cases (106) greatly outnumbered the Maori cases (40). The cause of this increase was the outbreak of typhoid fever at Kaikoura in October-November. A full report of this outbreak by Dr. J. H. Blakelock, Medical Officer of Health, Christchurch, is published in a somewhat condensed form as an Appendix to this report, and it is appropriate here to refer only to its main features. The outbreak was of an explosive nature, apparently tracible to an infected milksUpply. Prompt pasteurization of the milk was arranged for, and the outbreak terminated almost as suddenly as it had begun. A total of 78 persons were affected. A big strain was thrown on the local medical and hospital facilities, and the rapid control of the outbreak reflects credit on all concerned. The chief lesson to be learned from this outbreak is the importance of exercising adequate control over the hygienic handling of foods, and particularly milk. Given a similar set of circumstances the story could be repeated in many parts of New Zealand, and the general public is apt to forget the supreme importance of the enforcement of regulations for the hygienic handling of foodstuffs, which in ordinary times may appear to be irksome and unnecessary. In this case the price paid was a heavy one, as about 10 per cent, of the population at risk contracted the disease. There were 3 deaths. Poliomyelitis. —Notified cases numbered 134 (Europeans, 129 ; Maoris, 5). Up to the end of October only 9 cases had occurred, and of these only 3 had been reported for the months April to October. In the latter half of November, cases began to occur rapidly in the Auckland area, and by the end of the year there was a total of 125. Restrictions were imposed throughout the country on the gatherings and movements of children under sixteen. The outbreak continued throughout the summer, but was mainly confined to Auckland and South Auckland Health Districts, with a moderate number of cases in Taranaki.

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