West Nile Virus Found in Brussels Birds, Human Risk Low
The West Nile virus is now circulating among birds in Brussels, with the carcasses of three crows and a magpie found in Laken and Schaarbeek testing positive for the virus. Brussels Environment (Leefmilieu Brussel) confirmed the findings, while reassuring the public that complications from the virus are very rare in humans.
“We received several reports from citizens this week and are closely monitoring the situation,” a spokesperson for Brussels Environment said. The authority urged residents who find dead or sick animals not to touch them and to report them for testing.
A Growing Presence in Belgium
The Brussels detection marks the latest development in a summer that has seen the virus spread across multiple regions of Belgium. Earlier in August, the virus was detected in the Mechelen-Willebroek region and the Vilvoorde area, with several birds and a horse testing positive, according to VRT NWS.
On 7 August, the Federal Agency for the Safety of the Food Chain (FAVV) officially confirmed the first West Nile virus infection in a Belgian horse, located in the Brussels area of Wallonia. The animal, which showed severe neurological symptoms, was euthanized. “The West Nile virus has been detected in neighboring countries and many other regions in Europe in recent years,” the FAVV stated in its official announcement. “It is therefore no surprise that this virus is now also being detected in our country.”
How the Virus Spreads
The West Nile virus circulates primarily between mosquitoes and birds. Mosquitoes become carriers when they bite an infected bird, after which they can transmit the virus to horses and humans. Humans and horses are considered dead-end hosts and cannot transmit the virus further.
Health authorities emphasize that the risk to humans remains low. Approximately 80 percent of infected people show no symptoms at all, while about 19 percent experience mild flu-like symptoms such as fever, headache, or muscle pain. Only about 1 percent develop severe neurological complications, primarily older people or those with weakened immune systems, as detailed in VRT NWS’s explainer on the virus.
“The risk of illness is greater in older people or people with weakened health,” said Joris Moonens of the Flemish Care Department (Departement Zorg), which has alerted doctors and hospitals in affected regions. “So that doctors know that when they receive a patient whose symptoms they cannot immediately attribute to another disease, they also consider a possible West Nile virus infection.”
Blood Donor Testing Underway
As a precautionary measure, the Red Cross Flanders has begun testing blood donors in the Vilvoorde region—covering Vilvoorde, Zemst, Steenokkerzeel, Machelen, and Grimbergen—on instruction from the Federal Agency for Medicines and Health Products (FAGG), following the confirmed horse infection there. According to VRT NWS, spokesperson Jan Poté noted that Belgium is the only European country that tests blood donors upon a horse infection.
“The Red Cross has already conducted nearly 11,000 tests and has found no infection so far,” Poté said. He added that he expects a similar instruction for the Mechelen-Willebroek region in the coming days.
European Context and Climate Concerns
The virus is currently circulating in 12 European countries, including Italy, Greece, Spain, France, Germany, Romania, and North Macedonia, according to the European Centre for Disease Prevention and Control. In North Macedonia, at least five people have died in a current epidemic, as VRT NWS reported.
Meanwhile, a blood donor in the Dutch province of Utrecht was found infected with the West Nile virus in mid-August—the first human case in the Netherlands since 2020, as NRC reported.
Climate scientists link the virus’s northward spread to climate change. “This is the face of climate change,” said Wim Thiery, climate scientist at VUB, in VRT NWS’s analysis. “Alongside escalating climate extremes, the emergence of tropical diseases in Europe is unfortunately one of the many logical consequences of our addiction to oil, coal and gas.”
What Residents Should Do
There is no vaccine for humans, making mosquito bite prevention the only protection. Health authorities recommend wearing long sleeves and long pants, especially at dusk and night when mosquitoes are most active; using mosquito repellent; installing screens on windows and doors; and removing standing water in gardens and on terraces, where mosquitoes breed. The city of Mechelen and the municipality of Willebroek have published similar guidance for their residents.
For horses, two vaccines are available in Belgium, and owners are advised to consult their veterinarian about preventive vaccination.
What to Watch For
Authorities continue to monitor the situation closely as the mosquito season extends through October. Residents who find dead or sick birds are urged not to touch them and to report them to the relevant authorities. With the virus now detected in multiple regions of Belgium, health officials will be watching closely for any signs of human transmission as the summer draws to a close.