Biology and pathogenesis of chikungunya virus

Key Points Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that provokes arthralgia and, potentially, severe complications in humans. A multidisciplinary effort, carried out over the past 5 years, allowed a thoughtful characterization of this mysterious virus. Recently, there was an unexpectedly severe epidemic of CHIKV in countries of the Indian Ocean region. This outbreak seems to have been the result of a striking adaptation of the virus to a new arthropod, Aedes albopictus (the tiger mosquito). Analyses of isolates from this outbreak have resulted in several interesting findings regarding the clinical onset and physiopathology of this virus. Progress has also been made to further our understanding of the interactions of CHIKV with its human host, the cellular tropism of the virus and the mechanisms of triggering the innate immune response. Clinical development has also seen recent advances. Chikungunya virus is a re-emerging alphavirus that recently caused an epidemic in countries of the Indian Ocean. At the time, little was known about the biology and pathogenesis of this virus compared with other viruses, but recent multidisciplinary efforts have furthered our understanding of this pathogen and its interaction with the host. Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus responsible for a recent, unexpectedly severe epidemic in countries of the Indian Ocean region. Although many alphaviruses have been well studied, little was known about the biology and pathogenesis of CHIKV at the time of the 2005 outbreak. Over the past 5 years there has been a multidisciplinary effort aimed at deciphering the clinical, physiopathological, immunological and virological features of CHIKV infection. This Review highlights some of the most recent advances in our understanding of the biology of CHIKV and its interactions with the host.