European Union officials warned late last month there is a growing risk of mosquito-borne viral diseases such as dengue and chikungunya in Europe due to climate change, just days before the United States reported its first five cases of malaria in two decades.
The European Center for Disease Prevention and Control said that because Europe is experiencing a warming trend, with heat waves and flooding becoming more frequent and severe, and summers getting longer and warmer, the conditions are more favourable for invasive mosquito species such as Aedes albopictus and Aedes aegypti, The Associated Press reports.
The Stockholm-based agency said in a report that Aedes albopictus is a known vector of chikungunya and dengue viruses and has been establishing itself farther north and west in Europe. The other mosquito, Aedes aegypti, known to transmit dengue, yellow fever, chikungunya, zika, and West Nile viruses, has been established in Cyprus since 2022 and may spread to other European countries.
A decade ago, the Aedes albopictus mosquito was established in eight European countries, with 114 regions affected. This year, the mosquito is established in 13 countries and 337 regions, the ECDC said.
“If this continues, we can expect to see more cases and possibly deaths from diseases such as dengue, chikungunya, and West Nile fever,” said ECDC Director Andrea Ammon. “Efforts need to focus on ways to control mosquito populations, enhancing surveillance, and enforcing personal protective measures.”
Before, the diseases were imported from abroad, but “now we have domestically acquired cases,” Ammon told an online news conference.
Last week, as well, the U.S. Centers for Disease Control confirmed four cases of malaria in Sarasota County, Florida and one in Cameron County, Texas in people who had not travelled outside the country, the Washington Post reports. Since 1951, when the U.S. declared it had eliminated malaria, the country’s 2,000 or so cases per year have all involved travel overseas.
“It’s not panic time,” Brian Grimberg, associate professor of pathology and international health at Case Western Reserve University, told the Post. “I think the message is to be aware. I mean, Americans never think about malaria unless they travel abroad.”
The Post says malaria is considered “a serious disease with symptoms including fevers, headaches, chills, and flu-like illness.” The world sees 240 million cases per year, 95% of them in Africa.
In Europe, the ECDC said ways to control mosquito populations include eliminating standing water where mosquitoes breed, using eco-friendly larvicides, and promoting community awareness about mosquito control.
To protect themselves, people can use mosquito bed nets, sleep or rest in screened or air-conditioned rooms, wear clothes that cover most of the body, and use mosquito repellent, the ECDC said.
It added that raising awareness about diseases transmitted by mosquitoes is essential.
There is no specific treatment for dengue. While about 80% of infections are mild, severe cases can lead to internal bleeding, organ damage, and death.
Chikungunya fever, a debilitating disease suspected of afflicting tens of thousands, was first identified in Africa in 1953. It causes severe joint pain but is rarely fatal. There is no vaccine and it is mainly treated with pain medication.
Ammon said Europe reported 1,339 locally-acquired cases of West Nile infections, including 104 deaths, in 2022, the highest number since an epidemic in 2018.
West Nile fever symptoms can include headache, fever, muscle and joint aches, nausea, and fatigue. People with West Nile typically recover on their own, although symptoms may last for weeks to months.
The main body of this report was published by The Associated Press and republished by The Canadian Press on June 22, 2023.