H.—3l.

INCIDENCE BY HEALTH DISTRICTS. Table 13. —Showing Incidence of Notified Cases of Poliomyelitis, by Health Districts, 1936-37.

The incidence in different parts of the Dominion varied materially, Otago, where the epidemic originated, having the highest incidence, and Auckland Central, the most densely populated, the lowest. Thames-Tauranga, a rural area with no large towns, had the second highest incidence for " all cases " and the third highest for " paralytic " cases. INCIDENCE IN URBAN AND RURAL DISTRICTS (PARALYTIC CASES ONLY). In the four main centres of population —the cities of Auckland, Wellington, Christchurch, and Dunedin, including the boroughs contiguous or in close proximity thereto —the incidence of poliomyelitis was 3-4 per 10,000 of population. Auckland, the largest centre, had the lowest incidence, and Dunedin, the smallest centre, the highest incidence. In ten'smaller centres with population ranging from 11,000 to 26,000 the incidence rate was 4-6 per 10,000. For the remainder of the Dominion the rate was 4-5 per 10,000 of population. In the four main centres 26 per cent, of the paralytic cases were under five years of age and 37 per cent, between five and ten years. In the remainder of the Dominion 33 per cent, were under five and 27 per cent, between five and ten years. Nine per cent, of the cases in the four centres were twenty years of age or over, and 13 per cent, in the country areas. The age-groups from ten to twenty years did not differ markedly in town and country. MORTALITY. The deaths from poliomyelitis numbered 46, 42 European and 4 Maori. In addition, four deaths occurred from other causes in cases suffering from some degree of paralysis : A Maori male, six years of age, with paralysis of both legs, died six months later from rheumatic fever ; a male of six months, with paralysis of one leg, died six weeks later from septicaemia following an abscess ; a female of seven years with severe paralysis —legs, arms, and abdomen —died four months later from bronchopneumonia, and a male of eleven years with extensive paralysis —legs, arms, and abdomen—died six months later from broncho-pneumonia. Omitting these cases, which after inquiry were excluded from the list of deaths from poliomyelitis, the various fatality rates were : —

Of the Maori deaths 2 were of males aged thirty-six and fifty-six years and 2 of females aged two years and forty years respectively.

93

Incidence per 10,000 of Mean Population. Health District. (a) (6) All Cases. Paralytic Cases. North Auckland .. .. .. .. 3-36 3-21 Central Auckland .. .. .. 2-58 2-05 South. Auckland .. .. .. .. 5-23 4-04 Thames-Tauranga .. .. .. 9-69 6-34 Taranaki .. .. .. .. 6-85 6-41 Bast Cape .. .. .. .. 6-60 4-51 Wellington - Hawke's Bay .. .. 5-27 4-10 Central Wellington .. .. .. 4-34 3-21 Nelson-Marlborough .. .. .. 3-35 3-35 West Coast .. .. .. .. 4'94 4-94 Canterbury .. .. .. .. 6-13 3-89 Otago .. .. .. .. . • 12*98 8-32 Southland .. .. .. .. 5-85 4-29

Deaths per 100. (a) (b) All Cases. Paralytic Cases. European — Males .. .. .. 6-4 9-1 Females .. .. •• 3-2 4-3 Europeans .. .. .. 5-0 6-9 Maori— Males .. •• •• 6-5 7-7 Females .. •• 10-0 10-0 Maoris .. .. .. •• 7-8 8-7 Both races and both sexes.. .. 5-1 7-0