Sharan Apoorva, Das Manoja Kumar, Pm Akhil, Poluru Ramesh, Kashyap Neeraj Kumar, Burri Christian, Bonhoeffer Jan, Aneja Satinder, Polpakara Deepak, Arora Narendra Kumar
University of Basel, Basel Switzerland, Swiss Tropical and Public Health Institute (Swiss TPH), Allschwil, Switzerland, Inclen Trust International, New Delhi, India.
Inclen Trust International, New Delhi, India.
JMIR Res Protoc. 2025 Aug 8;14:e64050. doi: 10.2196/64050.
The rapid evolution of immunization programs in low- and middle-income countries (LMICs) has necessitated an augmentation of capacity for postlicensure vaccine safety monitoring.
This study describes the protocol for establishing a Multicenter Active Adverse Events Following Immunization Surveillance System (MAASS) network in India, which conducted prospective observational surveillance for 12 adverse pediatric outcomes between November 1, 2017, and March 20, 2020.
A multistage site selection process was implemented, beginning with an initial screening survey followed by in-person visits to assess the suitability of potential tertiary care hospitals for inclusion in the network. We adopted a decentralized, collaborative approach to develop the study protocol, standardize case definitions, establish data collection procedures, and create a common data model for monitoring and analysis. Outcomes selected for surveillance included acute disseminated encephalomyelitis, anaphylaxis, aseptic meningitis, dengue, Guillain-Barré syndrome, Kawasaki disease, malaria, seizure, sepsis, thrombocytopenia, intussusception, and urinary tract infections. We screened all children aged 1-24 months who were hospitalized for more than 24 hours at participating sites to identify suspected or confirmed cases of these outcomes using a structured checklist. Written informed consent was obtained from the parent or legally authorized representative for inclusion in the study. Demographic, socioeconomic, and vaccine exposure information was collected for all included participants. Additional clinical information was gathered to assess the level of diagnostic certainty according to standardized case definitions. The study progressed through 3 distinct phases: network establishment (January-November 2017), active surveillance (November 2017-March 2020), and database analysis (April 2020-March 2024). The dissemination process is currently underway.
A geographically representative data network was established across 15 public and 7 private tertiary care hospitals in 17 states and 1 union territory in India. During the study period, we screened 90,147 age-eligible admissions and confirmed 8362 cases with study outcomes. Using multiple analytic study designs, we generated a database of outcomes and exposures to investigate associations between vaccine-event pairs of interest.
The MAASS network is unprecedented in its scope and scale among LMICs. While the study is specific to India, the lessons learned in establishing and implementing the network offer valuable insights for developing active surveillance systems and strengthening capacity for benefit-risk evaluations of vaccines in resource-constrained settings.
INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/64050.
低收入和中等收入国家（LMICs）免疫规划的快速发展，使得加强疫苗上市后安全性监测的能力成为必要。
本研究描述了在印度建立多中心免疫接种后主动不良事件监测系统（MAASS）网络的方案，该网络于2017年11月1日至2020年3月20日对12种儿童不良结局进行了前瞻性观察监测。
实施了多阶段的站点选择过程，首先进行初步筛查调查，然后进行实地考察，以评估潜在的三级护理医院纳入该网络的适宜性。我们采用分散式协作方法来制定研究方案、标准化病例定义、建立数据收集程序，并创建一个用于监测和分析的通用数据模型。选择进行监测的结局包括急性播散性脑脊髓炎、过敏反应、无菌性脑膜炎、登革热、格林-巴利综合征、川崎病、疟疾、癫痫发作、败血症、血小板减少症、肠套叠和尿路感染。我们对在参与站点住院超过24小时的所有1-24个月龄儿童进行筛查，使用结构化检查表识别这些结局的疑似或确诊病例。获得了家长或法定授权代表的书面知情同意书，以将其纳入研究。收集了所有纳入参与者的人口统计学、社会经济和疫苗接种暴露信息。根据标准化病例定义收集了额外的临床信息，以评估诊断确定性水平。该研究历经3个不同阶段：网络建立（2017年1月至11月）、主动监测（2017年11月至2020年3月）和数据库分析（2020年4月至2024年3月）。传播过程目前正在进行中。
在印度17个邦和1个联邦属地的15家公立和7家私立三级护理医院建立了一个具有地理代表性的数据网络。在研究期间，我们筛查了90147名符合年龄条件的住院患者，确诊了8362例具有研究结局的病例。我们使用多种分析研究设计，生成了一个结局和暴露数据库，以调查感兴趣的疫苗-事件对之间的关联。
MAASS网络在低收入和中等收入国家中的规模和范围是前所未有的。虽然该研究特定于印度，但在建立和实施该网络过程中吸取的经验教训，为在资源有限的环境中开发主动监测系统和加强疫苗效益-风险评估能力提供了宝贵的见解。
国际注册报告识别码（IRRID）：RR1-10.2196/64050。
