13

H.—l9b

case mortality of 46 per cent. This lower death-rate, the delayed crest of intensity, and the rapid disappearance of the epidemic suggest that a certain degree of immunity had been conferred by the high primary wave of infection in September. General Characteristics of the Epidemic. The clinical features of the disease have been reported on by the Principal Medical Officers of the different camps, so I shall confine myself to the epidemiological features. It may be said, however, that the symptoms and complications generally coincide with those found in the reports of observers in Britain and America and elsewhere. They closely resemble also the clinical type of disease which produced so disastrous an epidemic on the transport " Tahiti " at the end of September. Save in the degree of fatality the same symptoms were seen in many cases arising in civil life in New Zealand in September and October, and in a few cases in the camps in those months. The following table shows the general incidence of influenza in camps and the larger military hospitals throughout the year 1918, being compiled from the hospital admission returns : —

Month. Fcatherston. Trentham. „ , Awapuni. Trentham. Narrow Neck. Awapuni. Awapuni i. Kotor Rotorua, Hanmer. I I I i January February March. .' April .. May . . June .. July .. August September October November December 8 23 .. 1 13 20 10 13 .. 3 3 14 .. 1 14 26 .. 2 8 13 99 78 .... 8 403 103 .. 54 326 877 .. 10 408 484 226 27 .. 3,174 1,566 206 147 6 5 23 20 13 14 26 13 78 103 877 484 1,566 5 1 1 3 1 2 8 54 10 27 147 226 206 10 27 147 151 151 8 29 6 Totals .-. I 4,522 3,227 432 253 132 '! I ! 253 151 43 Age Incidence. 20 to 24. - Under 20. 25 to 29. 30 to 34. 35 to 39. 40 and upwards. 20, 21, 22, 23, 24. 214 (vises influenza of primary wave —24th October to 3rd Novei 214 ci nber. Cases Cases Percentage a 3 52 13 9 0 8 42 44 82 1-4 24-3 6-0 4-2 .. 3-7 19-6 20-5 38-3 40 4 Percentage 18-6 1-4 2,248 cases influenza of secondary wave -4th November onwa: 2,2 •A. Cases Cases Percentage 80 545 148 79 39 56 436 483 867 3-5 24-3 6-6 3-5 1-7 2-5 19-0 21-5 38-5 292 90 Percentage 13-0 4-0 Cases Cases Percentage 3 237 cases broncho-pneumonia (out of a total of 301 cases). 4 30 19 10 5 13 53 67 77 1-6 12-6 8-0 4-2 2-1 5-4 22-3 28-2 32-5 27 10 Percentage 11-3 4-2 Cases Cases Percentage 3 161 deaths from influenza-pneumonia. 1 22 6 4 3 9 41 43 44 0-6 13-6 3-7 2-4 1-2 5-5 24-8 26-7 22 10 43 Percentage 26-7 13-6 6-2