Surge in Dengue Fever Across Europe Attributed to Invasive Tiger Mosquitoes
An invasive mosquito species has been detected in 13 EU countries, including France, Spain, and Greece, with experts linking this to a rise in dengue fever cases in Europe.
The European Centre for Disease Prevention and Control (ECDC) states that climate change is fostering conditions conducive to the spread of the tiger mosquito. This mosquito has been observed as far north as Paris, where the Olympic Games will be held in late July. Authorities there are actively monitoring and trapping the insect.
The ECDC warns that international travel could further heighten the risk of dengue outbreaks in Europe. To mitigate this, they recommend eliminating stagnant water from gardens or balconies to prevent mosquito breeding, and using repellents and mosquito nets at night.
In recent years, mosquitoes have increasingly posed a threat in Europe. The Asian tiger mosquito, Aedes albopictus, considered the world’s most invasive mosquito species, is expanding across Europe from its initial stronghold in southern Europe. The species is now established in Austria, Bulgaria, Croatia, France, Germany, Greece, Hungary, Italy, Malta, Portugal, Romania, Slovenia, and Spain. It has also been spotted in Belgium, Cyprus, Czechia, the Netherlands, and Slovakia.
These tiger mosquitoes can transmit diseases such as dengue fever, chikungunya, and the Zika virus, which were previously confined to parts of Africa, Asia, and the Americas. Another mosquito species, Aedes aegypti, known for spreading yellow fever, has been found in Cyprus, raising concerns about its potential to spread further into Europe due to its preference for biting humans and high disease transmission capability.
Asian tiger mosquitoes are progressively moving northward across Europe. Dengue fever starts with flu-like symptoms but can become severe and sometimes fatal. Mass outbreaks have increased in recent years, with France reporting eight incidents of multiple infections last year, Italy four, and Spain two. Most European cases are imported, reflecting the international movement of people and goods, with nearly 5,000 imported cases last year. However, local infections are also rising, with 130 cases in 2023, up from 71 the previous year.
West Nile virus, another mosquito-borne illness, is now present in more European regions than ever. An infection was reported in southern Spain in early March, underscoring how current climate conditions favor mosquito proliferation even “very early in the year,” according to the ECDC.
ECDC director Andrea Ammon emphasized that climate change is enabling invasive mosquitoes to spread into previously unaffected areas, increasing the risk of diseases like dengue. The rise in international travel from dengue-endemic countries will also elevate the risk of both imported and local outbreaks. Ammon advises taking personal protective measures and stresses the importance of early detection, timely surveillance, further research, and raising awareness in at-risk areas.
Dengue fever is endemic in over 100 countries, with more than six million cases and 7,000 deaths reported last year, according to the World Health Organization (WHO). The highest incidence is in Bangladesh, Malaysia, Thailand, and Vietnam.
Malaria, the deadliest mosquito-borne disease, also poses a potential future threat to Europe if conditions become favorable. It is transmitted by infected female Anopheles mosquitoes, which have been found in Europe. There are concerns that malaria incidents could also rise on the continent.
