“Dengue Fever Spreading to Europe: Risks, Symptoms, and Prevention”

Dengue or dengue fever is associated with the tropics, but in recent years it has spread rapidly to Europe, where the population is vulnerable because they have never been exposed to the virus before.

Late last year, a 44-year-old British woman died of an acute dengue infection while on holiday in the French seaside resort of Nice. Dozens of people fell ill in that local dengue outbreak. In 2022, a total of 7 deaths due to dengue will occur in Europe.

“Climate change, particularly warmer temperatures and increased rainfall, but also increased tourism and international trade, will make conditions for outbreaks in parts of Europe increasingly favorable,” Owain Donnelly of London’s Hospital for Tropical Diseases recently warned. He advocates more surveillance and reporting mechanisms to determine where dengue is spreading on the European mainland.

The dengue virus is transmitted through infected female mosquitoes of the genus Aedes, including the yellow fever mosquito (Temples of the Egyptians) and the Asian zeitgeist (Aedes albopictus), which are mainly found in tropical regions. But mosquitoes are also appearing more and more in Europe. And they bring the viruses.

Infectiologist Ula Maniewski of the Institute of Tropical Medicine (ITM) in Antwerp confirms that the Asian tiger mosquito is on the rise in Europe.

‘In many places this mosquito has settled and even survives the winters. To date, no people have been stung by an infected mosquito in Belgium. The species is not yet permanently present in our country. There will be occasional hearths found that are being eradicated. For example, we found the tiger mosquito in 12 places in Belgium last year. The more those mosquitoes spread, the higher the chance of dengue.’

Dengue fever is also on the rise in the rest of the world due to climate change. The disease is now endemic in 100 countries, but threatens another 29 countries. The number of cases has risen exponentially worldwide in recent years, from about half a million in 2000 to 5.2 million in 2019, the worst year on record.

The World Health Organization (WHO) even speaks of dengue as ‘one of the greatest threats of the future’.

Do you have to worry about your holiday in Southern Europe?

Many Belgians are going to the sun in Spain, Italy and France this summer, but there is no reason for great concern. Although cases of dengue infections have already been reported in Europe, the risk of infection remains low and the risk of serious illness is even lower. In any case, in Southern Europe it is always recommended to protect yourself against mosquitoes, Maniewski warns. ‘In Southern Europe, there are already various diseases that do not occur in Belgium and that are also transmitted by mosquitoes and other insects, such as West Nile fever. The Leishmania parasite is then transmitted by sand flies. Before you leave, check the potential health risks of your destination country, including in Europe. Do you need additional vaccinations? It is best to plan this well in advance, either with your doctor or through a travel clinic. Be aware that the period between the Easter holidays and the summer holidays is very busy in the travel clinics, so avoid that period.’

How dangerous is dengue?

In about 80 percent of cases, the disease progresses with mild symptoms or even asymptomatic. This means that patients hardly know, if at all, that they have dengue. This common form of dengue is quite harmless and goes away on its own after a few days without medical treatment.

But dengue is not completely harmless. It can even be fatal. 1 to 5 percent of patients develop a potentially fatal dengue haemorrhagic fever (DHF) of dengue shock syndrome (DSS). These conditions are especially dangerous for children.

Read more below the article.

How do you recognize dengue?

Those who experience symptoms will experience flu-like symptoms such as fever, headache, pain behind the eyes, nausea, muscle and joint pain (hence the term ‘dengue fever’) and skin rashes. The symptoms appear four to ten days after the mosquito bite. Symptoms of severe dengue include bruising, nosebleeds, bleeding gums, restlessness, or shock.

Is dengue contagious?

Dengue is transmitted by infected mosquitoes that are only active during the day, not at night. That poses an additional problem. Mosquitoes that spread malaria, for example, are mainly active at night. Mosquito nets are then an effective prevention measure to reduce the risk of malaria, but not for dengue. So it comes down to protecting yourself well during the day. Dengue is not contagious among humans.

What should you do if you are sick?

In most cases, the disease clears up on its own. In rare cases, the symptoms get worse after a few days. So be vigilant if you have had a mosquito bite while traveling.

Can dengue be cured?

If you feel unwell after a mosquito bite, get plenty of rest and drink plenty of water. Paracetamol can relieve the fever and pain somewhat. Avoid ibuprofen, as it can cause side effects in dengue.

To combat the virus itself, the Rega Institute in Leuven developed an antiviral agent. The drug is currently being tested in humans in clinical trials.

How can you protect yourself against dengue?

Prevent yourself from being bitten by a mosquito with covering clothing in neutral colors and with an anti-mosquito spray (DEET). Keep windows and doors closed and avoid places with standing water, as this is where the females lay their eggs.

Is there a vaccine?

There are four different types of dengue viruses. If you are infected by one of the viruses, you are immune to that variant for life. To be fully protected, you must therefore become infected by all four viruses. The downside, however, is that a second infection is often worse than the first.

Dengue vaccine development remains a major challenge. A dengue vaccine has been on the market since this year, but it is not yet available in Belgium. Vaccination is not yet recommended in Belgium and Europe.

The vaccine is mainly intended for people who have already had dengue and are traveling to endemic areas.

All information about the most important health risks and general recommendations per country can be found at www.wanda.be.