Description: Pneumococci can be divided into over 90 different serotypes depending on differences in their capsular polysaccharides. The different serotypes have different potential for causing severe disease and their distribution varies with age, geographical area and time point. The incidence of invasive pneumococcal disease by the serotypes included in the vaccine has declined in high-income countries since the pneumococcal conjugate vaccine was introduced in the childhood immunization schedule. After vaccine introduction, however, an increase of non-vaccine serotypes has been observed in various countries. This year, 2015, the pneumococcal conjugate vaccine was introduced in the childhood vaccination schedule in Cambodia. There is to date very limited data on the serotype distribution and incidence of invasive pneumococcal disease in Cambodia.
Goal: This collaborative study will involve Fondation Mérieux, Phnom Penh, Namru-2, Sihanouk Hospital Centre of Hope and Dr. Paul Turner, Angkor Hospital for Children (Cambodia-Oxford Medical Research Unit). It aims at mapping the serotype distribution of S. pneumoniae in Cambodia before the introduction of the conjugate vaccine, to serve as base-line data for future evaluation of the vaccination program. We will analyze stored samples of S. Pneumoniae that have been collected before December 31, 2014.