Prevention and control of perinatal hepatitis B virus transmission in ...

newborns with surface antigenemia, apparently acquired in utero, from becoming HBV carriers.Immunologic attempts to eliminate HBV may occur in carrier children infected in utero, despitetheir profound immune tolerance to HBV.Van Damme P, Vorsters A. Hepatitis B control in Europe by universal vaccination programmes:the situation in 2001. J Med Virol 2002; 67:433-439.Centre for the Evaluation of Vaccination, WHO Collaborating Centre for Prevention and Controlof Viral Hepatitis, Department of Epidemiology and Social Medicine, University of Antwerpen,Antwerpen, Belgium. pierre.vandamme@ua.ac.beIn the nine years since the Global Advisory Group of the Expanded Programme on Immunisation(WHO) set 1997 as the target for integrating hepatitis B vaccination into national immunisationprogrammes worldwide, 129 countries have included hepatitis B vaccine as part of their routineinfant or adolescent immunisation programmes (June 2001). By the end of 2002, 41 out of the 51countries of the WHO European Region will be implementing universal hepatitis B immunisation.The rewards of effective implementation of the programmes in countries that started 10 years agoare becoming apparent; and their success offers an exemplary model for other countries. Someother countries, however, have difficulties to incorporate hepatitis B vaccine into universalchildhood immunisation programmes, because of major economic constrains and the inability toprocure a constant vaccine supply. The next decade will be characterised by expanded use ofhepatitis B vaccines and the increasing efforts to sustain vaccine programmes and make thevaccine available to those countries and regions that cannot afford it. In Europe, as well as in therest of the world, work still remains to be done to support and implement interventions that willbring us closer to the WHO goal and to eradicate hepatitis B.Vranckx R, Alisjahbana A, Meheus A. Hepatitis B virus vaccination and antenatal transmissionof HBV markers to neonates. J Viral Hepat 1999; 6:135-139.Institute of Public Health, Brussels, Belgium.The high prevalence of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) inpregnant women is considered to be the most important factor contributing to the high carrier rateof HBsAg in some populations. Several factors, including the age at which infection occurs,predispose to the acquisition and frequency of the carrier state. The proportion of infected peoplewho become chronic carriers ranges from about 80 to 95% for babies born to HBsAg/HBeAgpositivemothers. In this study of Indonesian infants receiving only active immunization againstHBV, we measured the HBV markers passively acquired from their HBsAg-positive mothers. Therelationship of these markers with vaccination response and with HBV infection status was studiedlongitudinally in the infants. In the exposed neonates from the HBsAg-positive mothers (n = 61),the seroconversion rate to hepatitis B surface antibody (HBsAb) positivity was 95% after the firstbooster vaccination, with a geometric mean titre (GMT) of 2017 IU/l. After 60 months, the GMTin this group decreased to 50 IU/l. Four newborns in this group became HBsAg carriers. Of thefour vaccination failures, three newborns were HBsAg/HBeAg positive at birth, suggesting thatthey had been infected in utero. No vaccination strategy (active alone, or passive/active) canprevent this transmission from occurring. One carrier was HBsAg negative at birth and up tomonth 4 but was HBsAg positive at month 12 and subsequently, suggesting a postnatal infection.Vaccination early in life can, to a large extent, prevent perinatal transmission and hepatitis B virus(HBV) infection later in infancy and childhood. In this study, the protective efficacy of thevaccination was 85% in the subcohort of neonates from HBeAg-positive mothers and 100% in thesubcohort of neonates from HBeAg-negative mothers. Lack of maternal antibodies to hepatitis Bcore antigen (HBcAb) correlated strongly with transmission of HBV infection.41