Chikungunya

Chikungunya is transmitted to humans through the bite of an infected female Aedes mosquito—principally Aedes aegypti in tropical and subtropical regions, and Aedes albopictus (the Asian tiger mosquito) in temperate climates such as Italy. When a mosquito feeds on an infected person, the virus multiplies within the insect over an 8- to 10-day period, after which it remains capable of transmitting the infection for the remainder of its life. Direct person-to-person spread does not occur; consequently, travelers returning to the UK with the infection cannot pass it to others, and the UK lacks the consistently warm temperatures required for Aedes mosquitoes to breed and establish. Following an infectious bite, symptoms—most notably fever and joint pain—typically emerge within 4 to 8 days, though this incubation period can be shorter or longer in some individuals.