SEROPREVALENCE OF HEPATITIS-B VIRAL MARKERS IN 52,000 ALASKA NATIVES

As a part of a program to screen and immunize as many Alaska Natives a s possible against hepatitis B infection, hepatitis B virus seromarker s were measured in 52,022 Alaska Natives between 1983 and 1987. Hepati tis B surface antigen (HBsAg) was found in 1,603 persons (3.1%), and 7 ,155 persons (13.8%) exhibited hepatitis B virus seropositivity. While the prevalence of total seropositivity increased with increasing age (p < 0.001), the proportion of seropositive persons who were also posi tive for HBsAg was significantly higher in children under age 5 years than in persons over age 60 (p < 0.001). The total hepatitis B virus s eropositivity was significantly higher in males than in females (p < 0 .001), and a greater proportion of seropositive males than seropositiv e females had HBsAg (p < 0.001). The prevalence of HBsAg and total ser opositivity differed significantly by geographic region (p < 0.001), r anging from 0.5% to 8.2% for presence of HBsAg and from 5.4% to 29% fo r total seropositivity. Of persons who were HBsAg positive, hepatitis B e antigen was found in 35.4%, and antibody to hepatitis e antigen wa s found in 49.6%. The prevalence of hepatitis B e antigen significantl y decreased with age, while that of antibody to hepatitis e antigen si gnificantly increased. The prevalence of hepatitis B virus seropositiv ity is high in Alaska Natives, and there are significant differences i n both the prevalence of HBsAg and total hepatitis B virus seromarkers by age, sex, and geographic region.