Pneumococcal meningitis among hospitalised children after introduction of pneumococcal conjugate vaccine in India: a sentinel hospital surveillance (2019-2022).

Abstract

In 2017 India introduced the 13-valent pneumococcal conjugate vaccine (PCV13; Prevenar 13®) in select high-burden sites and in 2021, transitioned to nationwide introduction of 10-valent PCV (PCV10-SII; PNEUMOSIL®). We examined data from a large sentinel paediatric meningitis surveillance network to assess early changes in pneumococcal meningitis among hospitalised children after introduction of pneumococcal vaccine. Children (1-59 months) who were hospitalised with suspected meningitis at 32 hospitals across 19 states of India were enrolled in this hospital-based surveillance from 2019 to 2022. Clinical and demographic data were collected. Cerebrospinal fluid (CSF) samples were tested for <i>Streptococcus pneumoniae</i> using real-time PCR. Serotypes were identified using real-time PCR in TaqMan Array Cards. Cases were categorised based on PCV implementation in their district of residence on their admission date as pre-PCV (before rollout of PCV10-SII/PCV13), early-PCV (<1 year since rollout), or post-PCV (≥1 year since rollout) group. Among 12,971 children enrolled, 303 (2.3%) had pneumococcal meningitis; 65.3% were between 1 and 11 months of age, and 60.1% were males. Among 260 children with outcome data, 93.1% recovered, while 6.9% died during hospitalisation. The proportion of children with pneumococcal meningitis decreased from 3.5% pre-PCV to 1.8% during both early- and post-PCV periods. Among serotyped pneumococcal meningitis, the proportion of PCV10-SII serotypes was 41.4% in pre-PCV, 33.3% early-PCV, and 25.9% post-PCV periods. The most common PCV10-SII serotypes were 5, 14, and 6B whereas non-PCV10-SII serotypes were 18C/18B, 8, and 10F. Decline in the proportion of PCV10-SII serotype among paediatric pneumococcal meningitis patients represents preliminary signals of PCV impact in India. These findings provide programmatically relevant evidence to inform ongoing evaluation of PCV implementation. Continued surveillance is essential to monitor serotype distribution and pneumococcal meningitis patterns over time. Gates Foundation (OPP1188408) and the United Nations Development Programme (00101970).