Tamil Nadu Expands Japanese Encephalitis Vaccination to Seven Districts

In a significant public health initiative, the government of Tamil Nadu has announced the expansion of its Japanese Encephalitis (JE) vaccination program to include seven additional districts. This move aims to reduce the incidence of the disease, which poses a severe threat, particularly to children aged 1-15 years. The new districts set to benefit from this vaccination effort are Kancheepuram, Chengalpattu, Tirunelveli, Tenkasi, Vellore, Nagapattinam, and Chennai, as stated by Health Minister Ma. Subramanian during a press conference on June 29, 2025.

The initiative comes in response to alarming trends in JE cases reported in Tamil Nadu. According to a study conducted by Christian Medical College, Vellore, in collaboration with the Directorate of Public Health and Preventive Medicine, there has been a noticeable increase in JE cases in districts beyond the initially identified endemic areas. From January 2022 to December 2024, Tamil Nadu recorded 306 confirmed JE cases, with the majority affecting individuals aged 10-19. The study highlighted that Chennai had the highest proportion of cases at 40.5%, followed by Tiruvallur and Tiruvarur, with proportions of 8.2% and 6.2%, respectively.

JE is a viral infection primarily transmitted by mosquitoes, particularly the Culex tritaeniorhynchus species. Although symptomatic cases are rare, the World Health Organization (WHO) warns that the case fatality rate can reach up to 30%. Furthermore, lasting neurological, cognitive, and behavioral impairments can occur in 30% to 50% of those who survive encephalitis, emphasizing the critical need for widespread vaccination.

The expansion of the vaccination program is expected to benefit over 32 lakh children, as noted by Health Minister Subramanian. Vaccination camps will be established at government and private schools as well as Anganwadi centers. Village Health Nurses, trained specifically in immunization practices, will play an essential role in administering the vaccine to eligible children.

T. S. Selvavinayagam, Director of Public Health and Preventive Medicine, explained that the decision to broaden the vaccination coverage is part of a strategic effort to mitigate infant and child mortality rates associated with JE. The government has previously identified 14 districts as endemic to the virus, where over 58 lakh individuals have already received the vaccine.

The recent surge in cases, particularly in urban centers like Chennai, has prompted public health officials to reevaluate their strategies. The 2023 study, titled 'Epidemiological Profile of JE in Tamil Nadu, 2022-2024,' published in the Tamil Nadu Journal of Public Health and Medical Research, underscores the importance of targeted interventions and increased vaccination efforts to combat the rising threat of JE. The authors advocate for enhanced monitoring and the implementation of geographically focused control measures to address the growing public health concern.

As Tamil Nadu moves forward with this vaccination expansion, health officials emphasize the need for community engagement and awareness campaigns to ensure that parents are informed of the vaccine's availability and importance. By increasing vaccination coverage, the state aims to protect its most vulnerable populations from the devastating effects of Japanese Encephalitis, ultimately reducing mortality and enhancing public health outcomes.