Implication of pneumococcal conjugate vaccines to public health: Thailand perspective

The pneumococcal conjugate vaccines (PCVs) have demonstrated good safety profile and efficacy against invasive pneumococcal diseases (IPD) caused by the serotypes included in the vaccines. The PCV also benefit to the unvaccinated children and adults from herd immunity. With the widespread use of the vaccine, emerging of non vaccine serotypes has been documented. The IPD burden in Thailand was found to be lower than that found in the western countries but the data in high risk population has been lacking. The PCV has been available in Thailand since 2006 as an optional vaccine, out of National Vaccine Program, with the uptake of less than 5% in children under 5 years of age. The serotypes distribution in Thailand has not changed significantly. In the year 2000-2005, compared with year 2006-2009, the most common serotypes in children < 5 years have been similar; comprising of 6B, 23F, 14, and 19F, however 19A has become more prevalence (6.2%) in the years 2006-2009. With the new breakpoint of penicillin susceptibility for non-meningeal strains, most penumococcal isolates in Thailand were susceptible to penicillin. To project the benefit for widespread use of PCV in Thailand the cost benefit analyses including the different types of PCV, the various dosing schedule, the benefit from herd immunity and the disadvantage of serotype replacement are needed.