Daijiworld Media Network - New Delhi
New Delhi, Oct 2: A new global study has revealed that over 34.9 million people across the world are at risk of chikungunya infection annually, with South Asian nations — including India, Pakistan, and Indonesia — as well as Brazil, bearing the highest burden. India alone could see up to 12.1 million people at risk each year under a worst-case scenario.
The study, published in BMJ Global Health, was led by researchers from the London School of Hygiene & Tropical Medicine (LSHTM), Nagasaki University, and the International Vaccine Institute in Seoul. It found that the majority of the chikungunya burden comes from chronic disability, disproportionately affecting young children under 10 and adults over 60.
Transmitted by Aedes mosquitoes, the chikungunya virus causes large outbreaks in tropical climates, but the analysis suggests that its geographic reach is expanding. Researchers warned that infections could spread to areas previously not considered at risk due to climate and ecological changes.
Using high-resolution spatial models and extensive data from climatic, ecological, and socioeconomic factors, the team projected two scenarios. In the more conservative “focal scenario,” approximately 14.4 million people globally are at risk each year — with 5.1 million in India. In the more expansive “at-risk scenario,” global exposure could rise to 34.9 million, including 12.1 million in India alone.
India and Brazil were found to be the most affected, together contributing nearly half of the global burden in the focal scenario — India with 0.33 million disability-adjusted life years (DALYs) and Brazil with 0.11 million. South Asia accounted for the largest regional share of chikungunya-related disability at 44%, followed by Latin America and the Caribbean (26%), East Asia and the Pacific (20.5%), and Sub-Saharan Africa (6.9%).
“There’s a common assumption that chikungunya risk is limited to tropical regions,” said Hyolim Kang, lead author of the study. “But our findings show the threat is far more widespread.”
With no specific antiviral treatment available, care for chikungunya patients remains supportive, and the disease can result in prolonged pain and even permanent disability. Kang emphasized the urgency of preventative strategies, warning that even healthy individuals are not immune to the long-term impact of the virus.
The study highlights a growing need for public health preparedness, global surveillance, and investment in vaccine research as climate change and urbanization continue to alter the global footprint of mosquito-borne diseases.