Mosquitoes are advancing: why Europe is preparing for diseases once considered tropical

Not long ago, dengue fever, Zika virus, or chikungunya seemed to Europeans like something exotic from news reports about Southeast Asia or Latin America. But today these diseases are appearing more and more often in reports from European epidemiologists. The reason is simple: as the climate changes, so does the map of insect vectors carrying dangerous infections.

According to the European Centre for Disease Prevention and Control (ECDC), over the past two years Europe has recorded a record number of dengue and chikungunya cases transmitted by local mosquitoes. If the earlier concern was mainly about tourists bringing viruses back from abroad, today infections are already occurring on European soil.

Cyprus is on the front line

Specialists are paying particular attention to Cyprus today. According to the latest ECDC data, the presence of two dangerous mosquito species has been confirmed on the island — Aedes aegypti and Aedes albopictus, known as the tiger mosquito.

For Europe, such a combination is rare. It is Aedes aegypti that is considered the main carrier of dengue, chikungunya, Zika virus and yellow fever. The tiger mosquito is less efficient, but it is highly resilient and able to quickly adapt to new territories.

There are no signs of an epidemic in Cyprus for now. However, experts warn that if an infected person arrives on the island during mosquito season, the conditions for local transmission of the infection already exist.

Heat has become the insects’ ally

The main risk factor, experts say, is climate change. Milder winters and longer hot seasons allow mosquitoes to survive in places where this was once impossible.

Their active season is getting longer, and their range is expanding. As a result, Southern Europe is gradually turning into a comfortable environment for species that until recently were considered exclusively tropical.

But the problem is not limited to mosquitoes. In Cyprus, Hyalomma and Rhipicephalus ticks are widespread and can carry a number of dangerous infections, as well as Phlebotomus sand flies — vectors of leishmaniasis. This disease has long been known on the island and is regularly detected in dogs, which serve as the natural reservoir of the infection.

How Cyprus is defending itself

Perhaps the most interesting part is that Cyprus has been acting ahead of the curve for several years already.

• Traps for monitoring dangerous mosquito species have been installed across the island.
• Municipal services regularly treat storm drains, canals, construction sites and other places with standing water.
• After Aedes aegypti was detected, specialists began visiting residential neighborhoods, explaining to residents that even a small container of water in a yard can become a breeding ground for insects.
• In high-risk areas, biological control methods are used: fish that eat mosquito larvae are released into bodies of water.
• At the same time, modern population-reduction technologies are being studied, including the use of sterile males.

Interestingly, fighting mosquitoes is not new for Cyprus. Back in the first half of the 20th century, the authorities drained swamps and planted eucalyptus groves to eliminate malaria breeding grounds. It was then that the island managed to defeat a disease that for centuries had been considered one of the main threats to public health.

A new era of disease

The conclusion of European specialists sounds alarming, but realistic: Europe is entering an era of insect-borne diseases. Dengue, chikungunya, West Nile virus, Lyme disease and leishmaniasis are no longer exclusively problems of other continents.

Cyprus has become one of the first regions where the consequences of these changes are especially visible. And while it is still too early to speak of an emergency, the island has effectively become a testing ground for methods to combat threats that until recently were considered purely tropical.

It seems that in the 21st century, borders for viruses are changing as fast as the climate. And the question is no longer whether they will reach Europe, but how prepared Europe is to meet them.