H.—3l

12

Diphtheria in New Zealand, 1919-23.

Enteric Fever. The position as regards this disease for the period 1919-23 is shown in the table below :—

Enteric Fever in New Zealand, 1919-23.

The position with regard to enteric fever is most gratifying. As the table discloses, both incidence and death-rate in 1923 are lower than for any other year of the quinquennium. Tuberculosis. The notifications for 1923 show a decline in comparison with the preceding year, the figures being respectively 1,002 and 1,129. The next table, based upon death returns, gives a truer idea of the variations in the prevalence of this disease during the period 1914-23. Tuberculosis in New Zealand, 1914-23. Death-rate from p _ . , „ Number of Deaths Tuberculosis ~, ~ ~ ,P , Year. » m i. i • in «nn c otal Deaths from from Tuberculosis per 10,000 of ~ r, Mean Population. 1914 .. .. .. .. .. 728 6-67 7-17 1915 .. .. .. .. .. 693 6-30 6-95 1916 .. .. .. .. .. 742' 6-74 7-00 1917 .. .. .. .. ..755 6-87 7-17 1918 .. .. .. .. .. 832 7-54 5-08 1919 .. .. .. .. ..762 6-71 7-05 1920 .. .. .. .. .. 851 7-21 7-03 1921 .. .. .. .. ..793 648 742 1922 .. .. .. .. .. 821 6-56 7-48 1923 .. .. .. .. .. 792 6-21 6-88 The position disclosed by the table is, on the whole, a satisfactory one. It will be seen that the death-rate from tuberculosis for the year was exceptionally low, and, indeed, constitutes a record. Of the total of 792 deaths in 1.923, 619 were assigned to pulmonary tuberculosis, and the remaining 173 to other forms of tuberculosis. Influenza. The year under review was an influenza year. The outbreak began in the Otago Health District about June, and gradually worked its way north through the Dominion, lasting some three months, in each locality. The brunt of the disease, contrary to the experience of 1918, fell mainly upon the age-groups 30-50. For the whole of New Zealand 1,144 cases and 223 deaths were reported, as against 216 and 23 deaths in 1922, which may be regarded as a more or less normal year. The only types of the disease notifiable are, of course, the severe forms (pneumonic ,septicemic, and fulminant), so the figure 1,144 for notifications by no means represents the true prevalence for the year. Mild influenza was widespread and caused much minor illness. The following extract from the report of the Medical Officer of Health, Otago, is of very considerable interest as showing the pathology and. bacteriology of the disease, and the lack of success which attended the prophylactic use of a mixed influenza vaccine:— " During the epidemic, inoculation of the contacts of acute influenzal pneumonia cases with mixed influenza vaccine supplied by the Government Bacteriologist was performed in Dunedin and Invercargill. It cannot be said that this was attended with any proved benefits. On the contrary, many inoculated persons later contracted the disease in severe form.

Notifications. Deaths.* Year. Number Rate P er 10 ' 000 of Mean Population. Number. Rate per 10,000 j of Mean Population. 1919 1920 1921 1922 1923 3,499 30-61 2,442 20-48 2,611 21-33 1,989 15-89 1,951 15-31 157 95 107 78 68 1-37 0-81 0-87 0-62 0-53 * Figures include deaths from croup.

Notifications. Dei aths. Year. Number Rate per 10,000 of Mean Population. Number. Rate per 10,000 of Mean Population. 919 920 921 922 923 •• i 477 4-17 389 3-26 451 3-68 539 4-31 276 2-17 4-17 3-26 3-68 4-31 2-17 ■M 10 21 67 23 0-30 0-34 0-19 0-54 . 0-18