Hepatitis B and C virus infection among adult women in Jilin Province, China: an urban-rural comparison in prevalence of infection markers.

Twin seroepidemiological surveys on prevalence of hepatitis B and C virus (HBV and HCV, respectively) infection were conducted on 100 adult women in total, 50 each in the provincial capital of Changchun and in a farming village in the vicinity in Jilin Province, northeast China. Positivity to three markers on HBV (ie HBsAg+, anti-HBs+, and anti-HBc+) was examined by RIA methods, and to one on HCV (anti-HCV+) by EIA. The results were evaluated in combination with two foregoing studies in Shandong and Shaanxi Provinces, and with special reference to possible urban-rural differences in prevalence. The prevalence of HBsAg+ cases was rather low (ie 9% when two groups were combined), but that of anti-HBs+ and anti-HBc+ cases was high, being 50% and 45%, respectively. Thus, the rate of HBV+ cases was 62%. The rate for HCV+ cases was 3%. The comparison of the prevalence between the city group and the village group showed that the rates for anti-HBs+ and HBV+ were significantly or marginally higher in the former group than in the latter, respectively. The HCV+ prevalence rate for the city group (4%) also tended to be higher than the corresponding rates for the village group (2%), although the difference was statistically insignificant. When evaluated together with the observation in Shandong and Shaanxi Provinces, it appears possible to generalize that the HBV infection prevalence is not higher and probably lower in rural areas than in urban areas, and that such may also be the case for the HCV infection prevalence.

Two-site pan-species monoclonal antibody ELISA for detection of blood stage malaria antigen.

A two-site pan-species monoclonal antibody sandwich ELISA (MAb-MAb ELISA) was developed to detect both Plasmodium vivax and P. falciparum antigens in whole blood impregnated on filter paper. In this assay, the plates were coated with pan-species MAb 3F9 and another pan-species MAb M26-32 conjugated with alkaline phosphatase was used for detection of bound antigen. The sensitivity of this assay was 5, 10 and 10 parasites per 10(6) erythrocytes for cultured P. falciparum, patient-derived P. vivax and P. falciparum, respectively. The coincidence rates for this assay were 93% (92/99) with healthy individuals and 93% (42/45) with microscopically confirmed vivax malaria cases. After two weeks treatment, 77.7% (14/18) of vivax malaria were still positive by this assay but with diminished level of reactivities [corrected].