Integration of hepatitis B immunization in the Expanded Program on Immunization of the Child Survival Project.

ABSTRACT

PIP: The Expanded Program on Immunization (EPI) is a component of the Child Survival Project (CSP). Its objective is to reduce the incidence rates of measles, diphtheria, pertussis, tetanus, tuberculosis, and poliomyelitis by increasing effective vaccination coverage. In 1991, CSP/EPI developed a national plan to introduce national immunization of infants against hepatitis B, which is an endemic disease in Egypt. Hepatitis B virus (HBV) causes acute hepatitis and chronic liver disease. Studies have shown that by maturity most of the population has been infected with hepatitis A and greater than 50% with hepatitis B. The recommended series of 3 intramuscular doses of hepatitis B vaccine induces a protective antibody response (anti HBs) in 90% of healthy adults and 95% of infants, children, and adolescents. Several studies have shown that the currently licensed vaccines produce high rates of seroconversion ( 95%) and induce adequate levels of anti HBs when administered to infants at 2 months, 4 months, and 6 months of age. Scheduling was adjusted to coincide with the currently adopted 2, 4, and 6 month vaccination schedule for oral poliomyelitis virus (OPV) and diphtheria-pertussis-tetanus (DPT) to allow a delay of vaccination from 2 to 3 months following birth. Long term studies of healthy adults and children indicate the immunologic memory remains intact for at least 9 years and confers protection against HBV infection even though anti HBs levels may decline below detectable levels. Safety of hepatitis B vaccines has been verified through experience with millions of doses administered worldwide after licensure. Pain at the injection site (3-29%) and a temperature greater than 37.7 degrees Celsius have been the most frequently reported side effects among adults and children. Nearly 90% of children and 96% of newborns had no reactions to the vaccine. Any presumed risk of adverse events must be balanced against the expected risk of acute and chronic liver disease associated with hepatitis B virus infection.