Serotype distribution and antimicrobial susceptibility pattern in children ≤ 5 years with invasive pneumococcal disease in India – A systematic review

Background Streptococcus pneumoniae is a leading cause of childhood diseases that result in significant morbidity and mortality in India. Commercially licensed and available pneumococcal conjugate vaccines (PCVs) include ten (PCV-10) and 13 (PCV-13) pneumococcal serotypes. Vaccines with other serotype combinations are under development. Reviewing and reporting trends and distribution of pneumococcal serotypes causing invasive pneumococcal disease in India will be useful for policy making as PCV is being introduced into India's universal immunization program. Methods We conducted a systematic literature review of hospital based observational studies (both peer reviewed and gray literature published in English) from India available from January 1990 to December 2016. Studies that documented data on the prevalence of serotype distribution and the antimicrobial resistance pattern of S. pneumoniae in children ≤ 5 years of age were included. Result We screened a total number of 116 studies, of which 109 studies were excluded. Final analysis included seven studies. The most frequent pneumococcal serotypes causing invasive disease among children ≤ 5 years were 14, 1, 19F, 6B, 5, 6A, 9V and 23F. Serotype 14 and 19A were represented in most of the geographical regions studied in the reviewed articles. Currently available PCV formulations included 67.3–78.4% of all serotypes contributing to IPD among Indian children ≤ 5 years. Pneumococcal resistance to trimethoprim/sulfamethoxazole, erythromycin, penicillin, chloramphenicol, levofloxacin and cefotaxime was seen in 81%, 37%, 10%, 8%, 6% and 4% of all pneumococcal isolates respectively, while vancomycin resistance was not reported. Conclusion The present review demonstrates that up to 78.4% of reported invasive pneumococcal disease in children ≤ 5 years in India are currently caused by serotypes that are included in the available licensed PCVs. However, sentinel surveillance must be continued in representative parts of the country to assess the changing trends in distribution of pneumococcal serotypes and their implication for vaccine selection and rollout in India.