Recent figures from the European Centre for Disease Prevention and Control (ECDC) reveal a troubling increase in mosquito-borne diseases in Europe, with locally acquired dengue cases nearly doubling in 2023.
This surge shows a symptom of the broader global risk of climate change creating favourable conditions for disease vectors, potentially impacting regions far beyond Europe.
In 2023, Europe recorded 130 locally acquired cases of dengue fever, up from 71 in 2022. This sharp rise is attributed to the invasive tiger mosquito (Aedes albopictus), now present in 13 EU countries.
The ECDC’s director, Andrea Ammon stated: "Europe is already seeing how climate change is creating more favourable conditions for invasive mosquitoes to spread into previously unaffected areas and infect more people with diseases such as dengue."
The tiger mosquito, recognised for its black and white striped body, was previously confined to tropical regions, predominantly in Africa.
However, due to climate change, it has established populations in Austria, Bulgaria, Croatia, France, Germany, Greece, Hungary, Italy, Malta, Portugal, Romania, Slovenia, and Spain. It has also been detected at UK ports, although it has not yet established a foothold there.
This mosquito species is a carrier of not only dengue but also chikungunya and Zika viruses. Its spread into new areas is facilitated by warmer temperatures and increased rainfall, creating optimal breeding conditions.
The ECDC has warned that the tiger mosquito's expansion into new territories poses a significant public health risk, “necessitating robust surveillance and control measures”.
Dengue fever, often referred to as break-bone fever due to the severe joint pain it causes, can be fatal. The spike in locally acquired cases in Europe is concerning, given that in the decade from 2010 to 2021, only 71 cases were reported across the entire EU.
"Increased international travel from dengue-endemic countries will also increase the risk of imported cases, and inevitably also the risk of local outbreaks," said Ammon. This is corroborated by ECDC data showing that over 4,900 Europeans contracted dengue while travelling abroad in 2023, up from 1,572 cases in 2022.
The resurgence of mosquito-borne diseases is not confined to dengue. The yellow fever mosquito (Aedes aegypti), another vector of dengue, chikungunya, and Zika viruses, has made its way to Cyprus.
Additionally, Italy reported the presence of the malaria-spreading mosquito Anopheles sacharovi earlier this year, 50 years after the country was declared malaria-free.
The situation in Europe provides valuable insights for Southern Africa, where climate change could similarly expand the range of malaria-carrying mosquitoes.
South Africa has made significant strides in reducing malaria cases, but warming temperatures and increased rainfall could create favourable conditions for Anopheles mosquitoes.
Malaria is the most prevalent mosquito-borne disease present in South Africa. Although somewhat rare, cases are still reported within the north eastern regions, including parts of Limpopo, Mpumalanga, and KwaZulu-Natal provinces. These areas are near the borders with Mozambique, Zimbabwe, and Eswatini, where malaria transmission is common.
IOL