A new study has revealed that the excruciatingly painful tropical disease chikungunya can now be transmitted by mosquitoes across most of Europe, driven by the climate crisis and the spread of invasive mosquito species. The research, led by the UK Centre for Ecology and Hydrology (UKCEH), indicates that higher temperatures now allow for transmission for over six months of the year in southern European countries like Spain, Greece, and Italy, and for up to two months in south-east England.
The study is the first to comprehensively assess how temperature affects the incubation period of the chikungunya virus in the Asian tiger mosquito (Aedes albopictus), which has invaded Europe in recent decades. The researchers found that the minimum temperature for transmission is 13-14°C, significantly lower than the previous estimate of 16-18°C. This difference, described as “quite shocking” by lead author Sandeep Tegar, means the virus can spread in more areas and for longer periods than previously thought.
Chikungunya virus, first detected in Tanzania in 1952, causes severe and prolonged joint pain that can be debilitating and fatal in young children and older adults. While small numbers of cases have been reported in over 10 European countries in recent years, large outbreaks hit France and Italy in 2025, with France recording over 800 cases last year alone, up from just 30 in the previous decade. The virus is often carried by travellers from tropical regions where outbreaks occur.
The Asian tiger mosquito, which bites during the day, is moving northwards as temperatures rise. It has been detected in the UK but is not yet established. Dr Steven White of UKCEH noted that 20 years ago, the idea of chikungunya in Europe would have been dismissed, but “now everything’s changed.” He added, “We’re seeing rapid change and that’s the worry.”
Dr Diana Rojas Alvarez of the World Health Organization emphasised that up to 40% of patients still experience arthritis or severe pain after five years. She stressed that Europe still has a chance to control the mosquitoes through community education on removing stagnant water, wearing protective clothing, and using repellent, as well as establishing surveillance systems. The study, published in the Journal of the Royal Society Interface, analysed data from 49 earlier studies to determine incubation times across a full range of temperatures for the first time.
