Hepatitis B vaccination in the Philippines
Hepatitis B is a major public health problem in the Philippines with a population seroprevalence of 9% (Ruff, Bravo et al. 2009). Among the infected individuals, 20% to 30% will develop chronic liver infection mostly at ages 30-50 years. Annually an estimated 9 000 people die from chronic liver disease.
Effective and affordable drug treatment is still not available. Majority of chronic carriers acquire the virus either at the time of birth , at about 90% risk, or in early childhood by exposure to serous/blood exudates from cuts/wounds/bites of other infected children. Tthe risk of acquiring hepatitis B is approximately 30%, if the child is exposed between ages 1 year to 5 years. The risk is reduced to 10% if child is infected after five years old.
Based on current evidence, universal childhood immunization with three doses of hepatitis B vaccine is the most effective strategy to control hepatitis B. The vaccine is also effective in preventing infection if given immediately after exposure to infection (post-exposure prophylaxis).
In the Philippine setting, almost 10% of mothers may be chronic carriers of the virus, and at risk of transmitting the infection to their newborns at the time of birth (due to exposure of newborn to infected blood from mother. it is recommended to give the first dose of vaccine within 24 hours of birth to prevent mother to child transmission of infection.
If hepatitis B vaccine is not given at birth, even with sustained three doses of vaccine give at ages 6, 10 and 14 weeks, an estimated 3% to 5% of all infants will develop chronic liver infection, due to mother to child transmission at birth.
Hepatitis B vaccine was introduced, and is available in the Expanded Program on Immunization (EPI) since 1992 to the 40% of the infants. The goal is to increase coverage by an additional 10% of the population each year to reach 100% coverage by 1999 (Department Circular No. 242s.1990, “Implementing Guidelines on the Integration of Hepatitis B into the Expanded Program on Immunization” dated December 10, 1990).
However, insufficient allocation of fund to EPI limited the immediate full implementation of the Hepatitis B vaccination.
Pursuant to Republic Act No. 7846, otherwise known as the Compulsory Hepatitis B immunization among infants and children less than 8 years old, Hepatitis B vaccination shall be routinely strengthened. EPI plans and activities are geared towards effective of control hepatitis B in the country. The aim is to reduce the chronic infection rate of hepatitis B to less than 1% among future birth cohorts from the current levels of 10% to 12%.
In June 2011, Republic Act No. 10152 has been signed. It is otherwise known as the “Mandatory Infants and Children Health Immunization Act of 2011”, which requires that all children under five years old be given basic immunization against vaccine-preventable diseases. Specifically, this bill provides for all infants to be given the birth dose of the Hepatitis-B vaccine within 24 hours of birth.
Complementing this law, the government also passed Senate Bill Act No. 2029, otherwise known as the “Liver Cancer and Hepatitis B Awareness Month Act”, which declares February as the liver cancer and hepatitis B awareness month.