An excruciatingly painful tropical disease called chikungunya can now be transmitted by mosquitoes across most of Europe, a study has found.

Higher temperatures due to the climate crisis mean infections are now possible for more than six months of the year in Spain, Greece and other southern European countries, and for two months a year in south-east England. Continuing global heating means it is only a matter of time before the disease expands further northwards, the scientists said.

The analysis is the first to fully assess the effect of temperature on the incubation time of the virus in the Asian tiger mosquito, which has invaded Europe in recent decades. The study found the minimum temperature at which infections could occur is 2.5C lower than previous, less robust, estimates, representing a “quite shocking” difference, the researchers said.

Chikungunya virus was first detected in 1952 in Tanzania and was confined to tropical regions, where there are millions of infections a year. The disease causes severe and prolonged joint pain, which is extremely debilitating and can be fatal in young children and older adults.

A small number of cases have been reported in more than 10 European countries in recent years, but large-scale outbreaks of hundreds of cases hit France and Italy in 2025.