Universal screening for hepatitis B among pregnant women led to 96% vaccination coverage among newborns of HBsAg positive mothers in Denmark

In Denmark selective screening programs of pregnant women for hepatitis B missed 30-50% of high-risk groups and in late 2005 a universal screening of pregnant women for HBsAg was implemented.During a 2-year period a prospective enhanced surveillance of the universal screening was performed to examine the effectiveness of universal HBV-screening of pregnant women and HBV-immunizations of their newborn, and to provide a prevalence-estimate for HBV in Denmark. On a opt out basis all women in Denmark attending antenatal care were tested for hepatitis B serology. Vaccination data of the newborns and households of HBsAg positive pregnant women were assembled.Among 140,376 HBsAg tests of pregnant women, 371 (0.26%) were positive. The prevalence among women of Danish origin was 0.012% and 2.74% among foreign born women, highest for women from Southeast Asia (14.5%). Genotype C was the most prevalent (37%) and 13% had a HBVDNA ≥10⁸ IU/ml. The prevalence estimate of chronic hepatitis B in Denmark was 0.2-0.3% in the general population.Among children born within the project period, 96% received vaccination at birth compared to 50% of siblings born prior to universal screening. During 3 years of passive follow-up two transmissions (0.5%) have been notified. Among children born of the positive mothers prior to the trial-period 7.3% had been notified.Thus the prevalence of HBV positive mothers has more than doubled in Denmark over the last 40 years, but among women of Danish origin it has decreased 10-fold. By replacing selective screening with universal, identification of newborns in need of HBV-immunization was increased from 50% to almost complete coverage, and also identifies mothers with high viral load for evaluation of pre-term treatment to interrupt in utero transmission.