Sri Lanka is currently facing its most significant Chikungunya outbreak in nearly two decades, according to leading virologist Professor Neelika Malavige.
Professor Malavige, sharing her findings on the social media platform X, revealed that whole-genome sequencing of the virus strain was carried out using the Oxford Nanopore system.
The analysis confirmed that the circulating strain belongs to the Indian Ocean lineage (IOL), similar to those found in other South Asian regions.
“This marks the largest Chikungunya outbreak in Sri Lanka since the end of 2024, after 16 years without major transmission,” she stated.
The 2025 virus strain does not carry the E1:E226V mutation—commonly linked with transmission via Aedes albopictus mosquitoes—but does include the E1:K211E and E2:V264A mutations, which improve viral adaptation in Aedes aegypti, the primary vector in urban areas.
