The failure of the United Kingdom to introduce universal hepatitis B immunization means that most UK citizens are susceptible to infection, warns an infectious diseases expert in this weeks BMJ.
The UK is one of the few developed countries that still does not routinely immunize children against hepatitis B, despite a call by the World Health Organization for the global introduction of vaccine prevention programs by 1997, writes Andrew Pollard, Reader in Pediatric Infection and Immunity at Oxford University.
Earlier this year, the BMA also called upon the Department of Health to introduce the hepatitis B vaccine into the childhood schedule without further delay.
The main argument against introducing universal immunization is the relatively low incidence of disease in the UK compared with other countries. However, 180,000 people in the UK are chronically infected with hepatitis B virus and 7,700 new cases of chronic infection are detected each year.
Growing travel and migration also put the UK population at risk of exposure from abroad.
Up to 40 percent of infections are transmitted from mother to child during birth, or in early childhood through contact with blood or body fluids. Fortunately, the virus can be controlled and, possibly, eventually eliminated by immunization, says Pollard.
Indeed, countries that have introduced universal childhood immunization in the past 15 years now have a new generation of adolescents and young adults among whom transmission is being interrupted.
The UK government currently favors a targeted immunization strategy to prevent transmission of the virus from mother to child. But the easiest and cheapest way to protect UK children is to add hepatitis B vaccine to the current UK primary immunization schedule in early infancy, says Pollard. This approach is already widely used in Europe.
However, at this time, infant immunization alone is also insufficient to limit transmission of the virus, because of ongoing transmission among the non-immune adult population and the difficulty in identifying and reaching people at risk. For this reason, Pollard argues that the current targeted program aimed at high risk groups (injecting drug users, prisoners etc) needs strengthening to reduce the burden of new infections until those in a universal immunization program reach adulthood.
He also says that the recent proposal to introduce vaccination to prevent cervical cancer in pre-adolescents from next year could provide a vehicle for implementing a concomitant adolescent hepatitis B program to prevent liver cancer. This, he suggests, would generate a group of immune individuals more quickly than universal infant immunization alone and hasten the control of the hepatitis B virus in the UK.