Chikungunya, an arboviral disease transmitted by Aedes mosquitoes, has recently increased dramatically in incidence and geographic extent. Large outbreaks have affected islands of the Indian Ocean, India and other parts of South and Southeast Asia, Africa and most recently Italy. International travellers have disseminated new strains of the virus, some into regions from which chikungunya has hitherto been absent. In parallel, over the past 30 years international trade has resulted in the spread of A. albopictus from its original range in Asia, to all continents but Antarctica, thereby extending the geographic area over which transmission can occur.