JMIR Publications

ABSTRACT

Background:

Rapidly evolving immunization programmes in low- and middle-income countries (LMICs) have necessitated the augmentation of capacity for post-licensure vaccine safety monitoring in these countries.

Objective:

In the present manuscript, we describe the protocol for establishing a Multi-centre Active Adverse event following immunization Sentinel Surveillance (MAASS) network in India, which undertook prospective observational surveillance for 12 adverse paediatric outcomes between November 1st, 2017, and March 20th, 2020.

Methods:

A multi-stage site selection process was implemented, including an initial screening survey and subsequent in-person visits to assess the suitability of potential tertiary care hospitals for inclusion in the network. We undertook a decentralized, collaborative approach to develop the study protocol, standardize case definitions, establish data collection procedures, and developed a common data model for monitoring and analysis. Outcomes selected for surveillance included acute-demyelinating encephalomyelitis (ADEM), anaphylaxis, aseptic meningitis, dengue, Guillain-Barre syndrome (GBS), Kawasaki disease, malaria, seizure, sepsis, thrombocytopenia, intussusception, and urinary tract infections. We screened all children between 1-24 months of age, hospitalized for a duration of more than 24 hours at participating sites to identify suspected or confirmed cases of study outcomes using a structured checklist. We obtained written informed consent from the parent or legally authorized representative (LAR) for inclusion in the study. Demographic, socio-economic, and vaccine exposure information was collected for all included subjects. We collected additional clinical information to assess the level of diagnostic certainty according to standardized case definitions.

Results:

A geographically representative distributed data network was established across 15 public and seven private tertiary care hospitals in 17 states and one union territory in India. We screened 90,147 age-eligible admissions and confirmed 8,362 with study outcomes during the study period. We generated a database of outcomes and exposures to investigate associations between vaccine-event pairs of interest using multiple analytic study designs.

Conclusions:

The MAASS network is unprecedented in its scope and scale in low and middle-income countries. While the study is unique to India, the lessons learned in the establishment and implementation of the network provide valuable insights for building active surveillance systems and capacity for benefit-risk evaluations of vaccines in resource-constrained settings including LMIC.