The Heptavalent Pneumococcal Conjugate Vaccine Immunization Project by Bangkok Metropolitan in Thai Infants
Wongwat Liulak MD*, Usa Thisyakorn MD**
Affiliation : *Communicable Disease Control Division, Health Department, Bangkok Metropolitan, Bangkok, Thailand. **Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
Background : Streptococcus pneumoniae is the most common cause of bacteremia, sepsis, meningitis, pneumonia, sinusitis
and otitis media in children worldwide. Several studies have shown that the heptavalent pneumococcal conjugate vaccine
(PCV7) is highly immunogenic, safe and effective against disease caused by serotypes contained in the vaccine.
Objective : To determine the safety and efficacy of PCV7 administered to Thai infants.
Material and Method: Ninety-seven infants received four doses of PCV7. Three primary doses were given 2 months apart
starting at the age of 2-6 months and the booster dose at the age of 12-15 months. Reactogenicity and safety were evaluated
from parent reports. The impact of PCV7 on the occurrence of invasive pneumococcal disease (IPD) among vaccinees was
examined.
Results : PCV7 was well tolerated. Two infants reported low-grade fever. None of the vaccinees developed IPD during the 1-
year period following the first PCV7 dose.
Conclusion : Primary immunization followed by a booster dose of PCV7 appeared safe and efficactive in preventing IPD in
Thai children.
Keywords : Invasive pneumococcal disease, Pneumococcal conjugate vaccine, Thailand, Infants
