Seroprevalence of hepatitis B surface antigen (HBsAg) among first-time andsporadic blood donors in Greece: 1991-1996

Hepatitis B surface antigen (HBsAg) seroprevalence among three major groups of sporadic voluntary blood donors in Greece was studied and compared to t he seroprevalence in regular donors. These three groups share many characte ristics with the general population. A 6-year retrospective seroepidemiolog ical study was carried out (1991-1996). The study population consisted of d onors who were (i) military recruits (n = 80 302), (ii) enlisted military p ersonnel (n = 86 920) and (iii) directed family donors (n = 75 403). A spec imen was considered as HBsAg positive when found repeatedly reactive by a 3 rd-generation immunoassay and confirmed by RIA. The Mantel-Haenszel chi(2) procedure was used for stratified analysis of the prevalence rates and Gree nland/Robins confidence intervals of the respective weighted relative risk (MHRR) were calculated. The 6-year overall HBsAg seroprevalence among the t hree sporadic donor groups was 0.84%; this was twice the seroprevalence amo ng a sample of regular donors (n = 45 504) in Greece. Seroprevalence was hi gher among enlisted personnel (1.21 < MHRR = 1.34 < 1.50), during years pri or to 1995. Directed family donors had the same overall seropositivity rate as recruits and enlisted personnel. After 1995, all groups had a seropreva lence below 1%, possibly indicating a shift towards lower endemicity in the Greek population.