According to Natuur en Bos, the animals became ill after eating sick or dead birds.
The bird flu virus is still raging on our coast. Further research should now show whether foxes also spread the virus further among mammals.
If you see dead foxes or sick or dead birds, it is best to report this via the influenza line for dead and sick birds or to the Ostend Bird and Wild Animal Rehabilitation Center for dead foxes. More information can be found at the website of the Agency for Nature and Forests.