Kerala State in India was gripped by a renewed and widespread outbreak of Chikungunya virus (CHIKV) infection during 2007. Here, we report the A226V mutation in the glycoprotein envelope 1 (E1) gene of the virus among isolates collected from the three worst-affected districts of the state during this outbreak. This mutation had already been suggested to be directly responsible for a significant increase in CHIKV infectivity in . The badly affected districts in Kerala State during 2007 have abundant rubber plantations, which supported prolific breeding of mosquitoes. The abundance of in the region and molecular evolution of CHIKV may be contributing factors for the renewed epidemic of chikungunya fever during 2007.


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vol. , part 8, pp. 1945 - 1948

Details of inpatients included in the study during the 2007 fever outbreak in Kerala State, India

Fever cases recorded in Kerala State during 2007.

Suspected chikungunya cases reported in Kerala State during 2007.

[PDF file of Supplementary Table S1 and Figs S1 and S2](58 KB)


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