Baseline Assessment for Streptococcus pneumoniae of India Serotypes (BASIS)


In 2010 31% of deaths in children aged 1-59 months in India were due to pneumonia, totaling more than 253,000 deaths. In addition to causing pneumonia, pneumococcus causes other serious disease syndromes such as meningitis, bacteremia/sepsis and infections of other organ systems. Much of the morbidity and mortality due to pneumococcal disease could be prevented with routine use of licensed and available pneumococcal conjugate vaccines (PCV). Prior to 2017, PCV was not included in the routine immunization schedule in India, leaving the estimated 27 million children born each year susceptible to serious pneumococcal infections. 


BASIS  is a partnership led by the Johns Hopkins Bloomberg School of Public Health International Vaccine Access Center (IVAC), in collaboration with key Indian institutions, and is designed to establish a robust baseline estimate of pneumococcal serotype distribution prior to the introduction of PCV. BASIS conducted active and passive surveillance for pneumococcal isolates among children younger than 5 years of age with suspected invasive pneumococcal disease within 14 healthcare facilities from different regions around the country. A sub-study was conducted at the INCLEN Trust site in Palwal district, Haryana to provide pilot data of the pre-vaccine era serotype-specific pneumococcal colonization rates among children with pneumonia and among well children in the community.


Between September 2015 and September 2017, 3,357 children with suspected invasive pneumococcal disease were enrolled at active sites, yielding 170 pneumococcal isolates. An additional 127 pneumococcal isolates were identified from laboratory sites by passive surveillance. Among the total 297 pneumococcal isolates, common serotypes included 14 (18%), 19A (9%), 6B (9%), 19F (8%) and 5 (8%). The prevalence of PCV13-serotype among all isolates causing invasive pneumococcal disease among 1-59-month-old children was 76%. The BASIS study provides important nationally-representative data to support the introduction of PCV in India and evaluate the impact on pneumococcal serotype distribution.