H.—3l

In the table ten-yearly moving averages have been taken and the attack-rate and death-rate per thousand births calculated : —

Table showing Decennial Moving Average Attack-rates and Death-rates from Diphtheria per 1,000 Births.

I I I) ' ; It will be noticed that whilst in the decade 1910-19, which included the epidemic of 1916-17, there were 83' notifications of diphtheria for every 1,000 births, and 4-6 deaths from that disease, in the decade 1929-38 the notifications and deaths were 36 and 1-6 respectively per 1,000 births. There has been comparatively little diphtheria in New Zealand for some years, and as many children have never been exposed to infection and so have not acquired an immunity to the disease they are still susceptible. Delay in exposure to infection with the possibility of contracting the condition is an advantage, as the older the child when it contracts diphtheria the less the risk of a fatal termination. During the twelve years 1920-31 of those who contracted diphtheria the fatality-rate in various age-groups was as follows : Under one year of age .. •• •• 19-7 per 100 cases. One year and under five years .. • • • ■ ■ • 7-5 P er cases. Five years and under ten years . . . . • • • ■ 3-3 per 100 cases. Ten years and under fifteen years .. .. • • • • 1"7 P er 100 oases - Fifteen years and under twenty years . . • • • • 0-7 per 00 oases. As it cannot be expected that the incidence of diphtheria will not increase, and as young children are particularly susceptible, the opportunity should not be neglected of having such children immunized against the disease when immunization is being carried out in any district, (c) Acute Anterior Poliomyelitis. Following the epidemic of 1936-37, only 22 cases of poliomyelitis were notified during the year. Thirteen of these occurred in the Nelson-Marlborough Health District, an area which escaped lightly during the epidemic.

(d) Pulmonary Tuberculosis.

Infectious Diseases amongst Maoris. Table D attached gives the numbers of notifications of infectious disease received for members of the Maori race. The figures are not included in the European figures, as a large but decreasing number of cases amongst Maoris are missed, due to the fact that a proportion of Maoris fail to seek medical assistance when they become ill. With the extension of the district nursing service the position is P Of the 423 notifications received, 219 were of pulmonary tuberculosis, 65 of typhoid fever, and 33 of bacillary dysentery. These figures show a slight rise (7) in the number of cases of tuberculosis reported a marked drop in the notifications of typhoid fever, from 132 m 1937 to 65 in U3B, and an increase in bacillary dysentery from 11 cases in 1937 to 33 cases in 1938.

4—H. 31.

25

„ , Number Number Number Number f ,' of of Noti- T) t! Deaths fieations ™ S from Period. of Diph- gPeriod. ofJJmh- Diph . therm t j ? : Trfnn theria per 1,000 1.000 , 00Q Births. P-X°° Bl Births. 1910-19 .. •• •• 83 4-6 1920-29 .. .. •• 71 2-7 1911-20 .. •• 88 4-5 1921-30 68 2-6 1912-21 .. 93 4-6 1922-31 .. 64 2o 1913-22 .. 97 4-7 1923-32 60 2-4 1914-23 102 4-7 1924-33 58 2-2 1915-24 .. •• .. 108 4-6 1925-34 50 2-1 1916-25 108 4-5 1926-35 48 2-0 1917-26 .. ..107 4-1 1927-36 .. 43 1 9 1918-27 .. 92 3-4 1928-37 .. .. • 40 17 1919-28 .. ■■ 78 3-0 1929-38 .. ■ •• 36 1-6

Deaths. ! . Year. Number of Notifications. i , lem „ , Ratea per 10,000 of Number. I Mean population. 1934 I 824 491 3-32 1035 808 471 3-17 '• ' . ; 934 540 3-62 ila? ' * 915 494 3-28 1938 .. ■■ j 1.031 482 3-17