Where does chikungunya fever come from and how is it spread?
The chikungunya virus (CHIK V) is a RNA virus belonging to family Togaviridae, genus Alphavirus. It was first discovered in Africa in 1952-1953 and later introduced into Asia. The African and Asian strains of CHIK V differ biologically and spread of the virus occurs differently. In Asia, the mosquitoes Aedes aegypti and Aedes albopictus are the two main species involved in transmitting the virus from infected individuals to healthy contacts. In particular, Aedes aegypti breed in and around where humans live and usually bite during daylight hours. In Africa, CHIK V appears to be maintained in a cycle involving wild primates such as monkeys and baboons and forest dwelling species of Aedes mosquitoes. Major epidemics or outbreaks of chikungunya fever occur cyclically, a disease-free period of several years or decades may exist between the outbreaks. For example, a well-documented outbreak of the disease occurred in parts of India in 1963, 1964 and 1973. For the last 30 years there have be
