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

health care, is feasible and achieves satisfactory coverage rates. Intensive follow up is needed toimprove adherence to the immunisation schedule.Hipgrave DB, Maynard JE, Biggs B-A. Improving birth dose coverage of hepatitis B vaccine.Bull WHO 2006; 84:65-70.UNICEF Indonesia, Wisma Metropolitan 11, Jalan Sudirman 31, Jakarta 12920, Indonesia.dhipgrave@unicef.orgAdministration of a birth dose of hepatitis B vaccine (HepB vaccine) to neonates is recommendedto prevent mother-to-infant transmission and chronic infection with the hepatitis B virus (HBV).Although manufacturers recommend HepB vaccine distribution and storage at 2-8 degrees C,recognition of the heat stability of hepatitis B surface antigen stimulated research into its use afterstorage at, or exposure to, ambient or high temperatures. Storage of HepB vaccine at ambienttemperatures would enable birth dosing for neonates delivered at home in remote areas or at healthposts lacking refrigeration. This article reviews the current evidence on the thermostability ofHepB vaccine when stored outside the cold chain (OCC). The reports reviewed show that thevaccines studied were safe and effective whether stored cold or OCC. Field and laboratory dataalso verifies the retained potency of the vaccine after exposure to heat. The attachment of a highlystable variety of a vaccine vial monitor (measuring cumulative exposure to heat) on many HepBvaccines strongly supports policies allowing their storage OCC, when this will benefit birth dosecoverage. We recommend that this strategy be introduced to improve birth dose coverage,especially in rural and remote areas. Concurrent monitoring and evaluation should be undertakento affirm the safe implementation of this strategy, and assess its cost, feasibility and effect onreducing HBV infection rates. Meanwhile, release of manufacturer data verifying the potency ofcurrently available HepB vaccines after exposure to heat will increase confidence in the use ofvaccine vial monitors as a managerial tool during storage of HepB vaccine OCC.Hipgrave DB, Nguyen TV, Vu MH, Hoang TL, Do TD, Tran NT, Jolley D, Maynard JE,Biggs BA. Hepatitis B infection in rural Vietnam and the implications for a national program ofinfant immunization. Am J Trop Med Hyg 2003; 69:288-294.International Health Unit, The Burnet Institute, Alfred Medical Research & Education Precinct,Melbourne, Australia.To ascertain hepatitis B virus (HBV) infection rates for Vietnam, we surveyed HBV markers intwo districts of Thanh Hoa province. We randomly selected 536 infants (9- < or = 18 months old),228 children (4 to < or = 6 years old), 219 adolescents (14 to < or = 16 years old), and 596 adults(25 to < or = 40 years old). On questioning, none of those surveyed had received vaccine againstHBV. Hepatitis B virus surface antigen (HBsAg) and total HBV core antibody (anti-HBc) weremeasured in all specimens, and HBV e antigen (HBeAg) in those positive for HBsAg, and HBVsurface antibody (anti-HBs) were measured in all others. Current infection (HBsAg+) rates wereinfants = 12.5%, children = 18.4%, adolescents = 20.5%, and adults = 18.8%. Current or previousinfection (HBsAg+, anti-HBc+, or anti-HBs+) increased with age (infants = 19.6%, children =36.4%, adolescents = 55.3%, adults = 79.2%). Rates of HBeAg among those HBsAg+ were infants= 85.1%, children = 88.1%, adolescents = 71.1%, and adults = 30.4%. The epidemiology of HBVin Vietnam resembles that of many southeast Asian nations before introduction of vaccine.Immunization of newborns will have enormous impact on HBV-related morbidity and mortalitythere.19