[Study on the variations of hepatitis B virus status among people having received hepatitis B vaccine].

Objective: To study the epidemiological pattern and trends of hepatitis B virus (HBV) in the area where people had been immunized by HBV vaccine for long time.

Methods: Through cluster sampling and cross-sectional study, relative information and blood samples from people in Long-an county by families were collected. Signals of HBV infection were tested by solid-phase reverse immunosorbent test.

[Sensitivity, specificity and stability of the Tag-primer nested/multiplex PCR for malaria diagnosis].

Objective: To improve the sensitivity, specificity and stability of the Tag-primer nested/multiplex PCR for malaria diagnosis.

Methods: Filter paper blood samples were collected from 30 non-malaria fever patients and 20 infectious disease patients (common cold, influenza, typhoid, hepatitis, etc.).

Seroprevalence of hepatitis E virus infection, rural southern People's Republic of China.

Genotype 4 hepatitis E virus (HEV) is the dominant cause of hepatitis E in the People's Republic of China; swine are the principal reservoir. Our study was conducted in 8 rural communities of southern China, where families keep pigs near their homes. Phylogenetic analysis showed that 23 of 24 concurrent virus isolates from this region are genotype 4 strains.

Investigation on the epidemiological factors of Clonorchis sinensis infection in an area of south China.

To detect the epidemiological factors of Clonorchis sinensis infection in Hengxian County, one of counties in Guangxi Zhuang Autonomous Region where Schistosoma japonicum was endemic but eliminated in the late 1980s, a questionnaire was designed with 37 questions covering socioeconomic conditions and human behavior, contamination of the environment and fish ponds, inadequate farming/fishery practices; and the formalin-ether sedimentation technique was used to examine the feces of cats, dogs and pigs for the eggs of C. sinensis. Fresh fish was sliced and digested to detect the metacercariae of C.