High prevalence of hantavirus infection in a group of Chinese patients with acute hepatitis of unknown aetiology.

In southwestern China, small but substantial numbers of patients with acute hepatitis were found without known hepatropic viral infections (hepatitis A, B, C, D or E, cytomegalovirus, Epstein-Barr virus) and were receiving no hepatotoxic drugs. Prevalence of antibodies, both neutralizing and specific immunoglobulin (Ig)M and IgG, to Hantaan virus were evaluated in a cohort of 136 such patients: 83 were of unknown aetiology, 53 had known viral hepatitis and 59 healthy subjects acted as controls. The results showed that the incidence of neutralizing antibody to Hantaan virus in acute hepatitis patients with non-hepatitis A-E virus infections (13 of 83) was significantly higher than in those with A-E infections (0 of 53, P<0.01). Furthermore, the incidence of specific IgM antibody to Hantaan virus in acute hepatitis patients with non-hepatitis A-E virus infections (6 of 83) was significantly higher than in those with A-E infections (0 of 53, P<0.05) and in healthy subjects (0 of 59, P < 0.05). These findings suggest that Hantaan virus may be an important agent, contributing, at least in southwestern China, to a significant number of the cases of acute hepatitis of unknown aetiology. This hantavirus infection resulted in an acute hepatitis, differing from the typical diseases: haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS).

[A population-based study on types of viral hepatitis].

The epidemiological features of various types of acute viral hepatitis in 5 regions of Sichuan Province (211,639 population) from Feb. 16, 1987 to Feb. 15, 1988 were studied. The results of the study showed that the incidence of acute viral hepatitis was 167.74 per 100,000 and the proportion of HA, HB, NANBH, HEB, HCM, MIXED infection in all the patients was 24.51%, 38.31%, 24.51%, 3.38%, 3.38%, and 5.92 respectively. There was an incidence of 14.93% for multiple infections. Large incidence differences in these regions (from 110.30 per 100,000 to 299.95 per 100,000) were noted. The sex ratio (male: female) for acute viral hepatitis was 1.75:1. There was a peak attack rate of HA in 0-19 age group. The incidence of HB in 20-39 age group was obviously higher than those in other age groups. For NANBH, attack rate was relatively high in 5-19 age groups. There were no significant age-differences for HEB, HCM and mixed infections.

[Study of logistic curve fitting for primary liver cancer death rate in Chengdu].

Logistic curve was used for fitting primary liver cancer (PLC) age-specific death rate in Chengdu. The results showed that the age-specific death rate from 1981 to 1986 in Chengdu (population about 4,000,000) was satisfactorily fitted by logistic curve in male, female and total (P less than 0.01). The R2s were 0.9885, 0.9912 and 0.9974, respectively. Velocity analysis of death rate showed that the increasing peak was in the group of age 40-60 for male and 50-65 for female. Male's velocity and slope of death rate were higher and steeper than female's. These results are consistent with the feature of logistic curve and parameters obtained from logistic curve fitting in this study. The age-specific death rate by sex for every year from 1981 to 1986 was fitted very well (P less than 0.01). R2s for male and female were 0.9415 +/- 0.044 and 0.9056 +/- 0.048, respectively.