SCHISTOSOMIASIS-JAPONICA ON JISHAN ISLAND, JIANGXI PROVINCE, PEOPLES-REPUBLIC-OF-CHINA - PERSISTENCE OF HEPATIC-FIBROSIS AFTER REDUCTION OFTHE PREVALENCE OF INFECTION WITH AGE

Hepatic fibrosis due to schistosomiasis japonica was examined by ultra sonography in a cross-sectional community study of 825 individuals on Jishan Island, Jiangxi Province, China. The prevalence of active infec tion was 39.4% with peak infection in the 10-19.9 years age group foll owed by a significant decline. A similar pattern was observed for inte nsity of infection. The prevalence of hepatomegaly in the midsternal l ine greater-than-or-equal-to 6 cm peaked at 60% in the fourth decade a nd remained elevated. A progressive increase in the severity of hepati c periportal fibrosis was observed with age, with advanced fibrosis pe aking in the fifth decade. The proportion of individuals with advanced fibrosis was significantly greater in males than in females despite e quivalent prevalence and intensity of schistosome infection. In additi on, a positive association (P<0.01) was found between periportal fibro sis and both hepatomegaly greater-than-or-equal-to 6 cm and splenomega ly. This study suggests that the natural history of schistosomiasis ja ponica in this hyperendemic community in China is marked by persistenc e of hepatomegaly and schistosome-induced periportal fibrosis in adult s despite a decrease in the prevalence of infection.