Peer-reviewed article
Japanese encephalitis among children in India: proportion of cases, case fatality, and epidemiological patterns - a systematic review and meta-analysis.
N Siva, Krishna Kumari Samantaray, Pravati Tripathy, Baby S Nayak, Deena Sivakumar et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This systematic review analysed 36 studies involving nearly 70,000 participants to understand Japanese encephalitis (JE) in Indian children. Children make up 15-34% of confirmed JE cases in India, and about 18% of diagnosed child cases are fatal. While vaccination coverage for the first dose exceeds 95% in some districts, second-dose coverage is lower (81-88%), and barriers include delayed uptake and parental hesitancy. The review calls for better surveillance, complete immunization coverage, and improved early case management to reduce child deaths from JE.
Key points
- Pooled proportion of children among confirmed JE cases: 15-34% (95% CI)
- Pooled case fatality proportion among pediatric JE cases: 18% (95% CI: 14%-23%)
- First-dose JE vaccination coverage frequently exceeded 95%, but second-dose coverage ranged 81-88%
- Clinical manifestations in children dominated by fever, seizures, and altered sensorium
- Barriers to complete vaccination include delayed second-dose uptake, parental hesitancy, and access-related challenges
Limitations
The pooled proportion of children among cases reflects hospital-based and surveillance cohorts rather than true population-level prevalence. Substantial heterogeneity was observed across studies (I²=98.8%), which may reflect differences in case definitions, settings, and reporting quality across the included studies.
Abstract
BACKGROUND: Japanese Encephalitis (JE) remains a major cause of viral encephalitis in India, disproportionately affecting children in endemic regions. Although vaccination programs have reduced incidence in several districts, seasonal outbreaks and pediatric mortality continue to be reported. This systematic review and meta-analysis aimed to estimate the pooled proportion of children among laboratory-confirmed JE cases and the pooled case fatality proportion among pediatric JE cases in India. Secondary objectives included narratively synthesizing morbidity patterns and vaccination coverage. METHODS: This review was conducted in accordance with MOOSE guidelines and registered with PROSPERO. PubMed, CINAHL, Scopus, ProQuest, Web of Science, and J-Gate were searched for studies published between January 2011 and August 2025. Additional sources included Google Scholar, Indian journal platforms, and official national and state health department reports. Observational and surveillance studies reporting pediatric JE data from India were included. Two reviewers independently performed screening, data extraction, and quality appraisal using the Joanna Briggs Institute (JBI) checklist for prevalence studies. Random-effects meta-analysis was used to estimate pooled proportions. Heterogeneity was assessed using I² and Tau² statistics. Publication bias was examined using funnel plots and Egger’s regression test. RESULTS: Thirty-six studies comprising 69,905 participants were included. The pooled proportion of children among confirmed JE cases was (95% CI: 15%-34%; p < 0.001; I² = 98.8; Tau² = 2.1919) reflecting the share of pediatric cases within included hospital-based and surveillance cohorts rather than population-level prevalence. The pooled case fatality proportion among pediatric JE cases was 18% (95% CI: 0.14%-0.23%; p < 0.001; I² = 98.4; Tau² = 0.3702). Substantial heterogeneity was observed across studies. Clinical manifestations were dominated by fever, seizures, and altered sensorium. Vaccination coverage for the first dose frequently exceeded 95%, whereas second-dose coverage ranged between 81 and 88% in reported districts. Barriers included delayed second-dose uptake, parental hesitancy, and access-related challenges. CONCLUSIONS: Children account for a substantial proportion of JE cases in endemic Indian settings, and nearly one in five diagnosed pediatric cases results in death. Despite vaccination efforts, regional disparities and surveillance variability persist. Strengthening standardized surveillance, improving complete immunization coverage, and enhancing early case management are essential to reduce pediatric JE mortality in India.