[The current prevalence of intestinal parasites in Beijing].

Following the requirements of the "National survey on the current status of the major human parasitic diseases", the investigation was conducted in June-October 2002 in 5 districts (counties) of Beijing with a sample of 7912 people. The overall prevalence rate of intestinal parasites was 2.9%, significantly lower than the result from the first survey in 1988-1989 (34.

[Observation on effects of hepatitis B vaccine immunization for 12 years in children in Beijing].

Objective: To evaluate the long-term protective effects of hepatitis B vaccine after immunizing to the children for 12 years in Beijing.

Methods: The multiple stratified cluster sampling was used in this epidemiological survey. The sampling children's blood serum HBsAg, anti-HBs and anti-HBc were checked and measured by the solid phase radioimmunoassay (SPRIA).