Hospital-based sentinel surveillance for Streptococcus pneumoniae and other invasive bacterial diseases in India (HBSSPIBD): design and methodology.

Introduction Streptococcus pneumoniae is one of the frequently isolated organisms and an important aetiological agent of invasive bacterial diseases (IBD) like pneumonia, meningitis and sepsis. As a measure to control the burden of IBD, the Government of India introduced Pneumoccocal Conjugate Vaccine-13 (PCV-13) in the Universal Immunization Program in high burden districts of five states in a phased manner from 2017 onwards. It is essential to understand the trend of circulating pneumococcal serotypes associated with IBD in the prevaccination and postvaccination scenarios to decide on the expansion of vaccination programmes and PCV reformulation. This manuscript describes the protocol for hospital-based sentinel surveillance for S. pneumoniae and other organisms causing IBD across various geographical regions in India. Methods and analysis Hospital-based surveillance is established in selected hospitals to recruit children aged 1-59 months with symptoms of pneumonia and other IBD. Diagnostic criteria were adapted from standard WHO case definitions. Case Report Forms (CRFs) are used to collect data from the enrolled children. Blood, cerebrospinal fluid (CSF) and other normally sterile body fluids are collected and subjected to microscopy, cytology, latex agglutination, biochemistry, bacteriological culture and real-time PCR as applicable. Pneumococcal isolates are serotyped and tested for assessing antimicrobial resistance patterns. Data will be analysed by simple descriptive statistics to estimate the proportion of pneumonia and other IBD due to S. pneumoniae, Hemophilus influenzae type b and Neisseria meningitidis. Prevalence of bacterial infection, circulating pneumococcal serotypes, antibiotic resistance patterns, serotype variability across seasons and regions will be described in terms of percentage with 95% confidence interval.