Control of hepatitis B through routine immunization of infants: the need for flexible schedules and new combination vaccine formulations.

Universal immunization of infants is essential to the control of hepatitis B in areas of high endemicity where infection commonly occurs in infants and children. It is also an attractive strategy for ultimately reducing hepatitis-B-associated acute and chronic liver disease in areas of lower endemicity where infections occur primarily in adolescents and adults. Integration of hepatitis B vaccine with other routine paediatric immunizations, using flexible scheduling, will enhance compliance while minimizing the need for additional resources. Clinical studies demonstrate that a very high proportion of healthy infants and adults develop a protective level of antibody when given hepatitis B vaccine using a wide range of schedules. Compliance with universal vaccination of infants against hepatitis B may be enhanced by the development of new combination vaccines (e.g. diphtheria-tetanus-pertussis-Haemophilus influenzae b-hepatitis B) that allow complete immunization against several antigens with a minimal number of injections.