Chandipura virus resurgence: Insights from Indian outbreaks and the path forward.

Background: First isolated in 1965 from a case of febrile encephalopathy, the Chandipura virus (CHPV) causes sporadic cases as well as periodic outbreaks of encephalitis in parts of India. Transmitted by sandflies and mosquitoes, CHPV infection has high mortality within 48 h of hospitalization, with children bearing the brunt of the illness. The virus garnered global attention in the middle of 2024 as India witnessed its largest outbreak in the last two decades.

Objective: This article aims to synthesise the existing knowledge on various aspects of CHPV and outline current actions needed as well as potential directions for future research.

Content: Between early June and August 15th, 2024, India reported 245 cases of encephalitis from the states of Gujarat and Rajasthan, 64 of which were laboratory-confirmed CHPV infections. The mortality toll of the outbreak was 82, accounting for a case fatality rate of 33 %. With this outbreak, the virus has expanded its niche from central and southern to north-western India. Significant advancements in the understanding of the neuropathogenesis of the virus and the development of diagnostic assays have been made in the 21st century. However, no specific antiviral drugs or vaccines are available. A G-protein-based recombinant vaccine and an inactivated vaccine have shown favourable results in pre-clinical trials. The need of the hour is to fast-track the development of an effective vaccine. A high suspicion for early identification and prompt referral of cases, decentralized diagnostic facilities, sensitization of healthcare workers, integrated vector management and effective reporting and surveillance systems are all needed to curb the menace of this perilous pathogen. The current outbreak should serve as a wake-up call to foster intersectoral collaboration between policymakers, public health experts, epidemiologists, virologists, neurologists, paediatricians, and anthropologists to develop and implement effective strategies against the virus.