Chikungunya virus: host pathogen interaction.

Chikungunya is a re-emerging arthropod-borne viral disease caused by Chikungunya virus (CHIKV) belonging to the Togaviridae family of genus Alphavirus. It is a virus with a single stranded, positive sense RNA, as its genome. It is maintained in a sylvatic and urban cycle involving humans and the mosquito species Aedes aegypti and Aedes albopictus. It has garnered the attention of scientists in the past 5-6 years due to the massive outbreaks in the Indian Ocean region in 2005-2006. It has a major health impact on humans as it causes fever, rashes, arthralgia and myalgia. Polyarthralgia is the most important feature of CHIKV infection which primarily affects the small joints of the wrists and fingers along with the large joints like shoulders and knees. Currently, there are no vaccines or treatment regimens available for CHIKV infection. The molecular mechanism underlying the chronic polyarthralgia observed in patients is not well understood. In this review we have summarized the CHIKV organization, replication, epidemiology, clinical manifestations and pathogenesis with emphasis on the arthralgia.