A large waterborne viral hepatitis E epidemic in Kanpur, India S.R. Naik,1 R. Aggarwal,2 P.N. Salunke,3 & N.N. Mehrotra4 In 1991 the largest epidemic of viral hepatitis E yet reported occurred in Kanpur (population, 2.1 million), India. The incidence of icteric hepatitis from December 1990 to April 1991 among the inhabitants of 420 randomly sampled houses in seven of the city's 50 wards was 3.76% (138 out of 3666 individuals), i.e., an estimated 79091 persons in the city as a whole were affected. The attack rate was higher for males than females (5.3% versus 3.3%; P = 0.013) and for adults than children aged 0.05. 16 13 18 34

95 96 110 72 373 40 182 62 284 657

Table 2: Age and sex distributions of hepatitis cases in the sample survey No. of persons Age group Male Female (years) Total 0-9 2 6 8 (5.8) a 10-19 29 19 48 (34.8) 20-29 31 15 46 (33.3) 30-39 10 8 18 (13.0) 7 40-49 2 9 (6.5) 50-59 5 2 7 (5.1) 1 260 1 2 (1.5) Total 89 49 138 a Figures in parentheses are percentages.

ary and a major and sustained peak in the latter half of March and in April 1991 (Fig. 2).

Incidence of hepatitis and the water supply The incidence of hepatitis in the MW areas varied from 1.6% to 10.4% (mean, 5.6%), while that in the TW areas varied from 1.0% to 2.5% (mean, 1.2%). The incidence in the MW areas was significantly higher (X2 = 45.01, P