Abstract
We estimated the weighted mean basic reproduction number (R(0)) of chikungunya virus based on outbreak size. R(0) was 3.4 (95% CI 2.4-4.2) and varied for 2 primary chikungunya mosquito vectors: 4.1 (95% CI 1.5-6.6) for Aedes aegypti and 2.8 (95% CI 1.8-3.8) for Ae. albopictus.