Risk of Dengue and Chikungunya Becoming Endemic in Europe Due to Climate Change

Recent research highlights a concerning trend: the tropical diseases dengue and chikungunya may soon establish endemic presence in Europe. This shift is linked to the expanding reach of the tiger mosquito (Aedes albopictus), known for transmitting these viruses. As global temperatures rise, particularly due to human-induced climate change, the mosquito's habitat is extending further north, increasing the risk of disease transmission at previously unaffected locations.

Historically confined to tropical regions, over half of the world's population is now at risk of contracting these viruses. Both dengue and chikungunya can cause severe fevers, and in rare cases, they can be fatal. The primary vectors are Aedes aegypti and Aedes albopictus mosquitoes. The latter, commonly called the tiger mosquito, has become more prevalent in Europe, especially during warmer years.

A recent study published in The Lancet Planetary Health analyzed data from the past 35 years and found that the frequency and severity of outbreaks have increased since 2010, correlating with rising temperatures. Notably, in 2024—considered the warmest year on record—Europe reported over 300 cases of dengue, marking an increase from approximately 275 cases in the prior years. Countries such as Italy, France, Croatia, and Spain have all experienced outbreaks.

Scientists warn that Europe is transitioning from sporadic cases to potential endemic transmission of these diseases. Models suggest that under worst-case climate change scenarios, outbreaks could multiply fivefold by 2060. Interestingly, outbreaks tend to be more detected in wealthier regions, partly due to better testing, but cases might be underreported in poorer areas.

In addition to dengue and chikungunya, tiger mosquitoes can transmit other viruses like Zika and West Nile. The recent outbreak of chikungunya on Reunion Island, a French overseas territory, underscores the potential health threats posed by expanding mosquito habitats.

This evolving situation underscores the importance of monitoring climate trends, implementing vector control strategies, and increasing public health preparedness to mitigate the risks of these mosquito-borne diseases in Europe.