The mosquito borne West Nile virus has been found for the first time in a person who had not been abroad, health institute RIVM has said.
Other people in the Netherlands have been found to have the virus but these cases were always traced to a stay abroad.
The virus has been found in birds and mosquitos in the Utrecht region, which is where the man probably contracted it, the RIVM said.
Horses and people can get the virus but do not spread it. The chance that many people will get the virus is small, the heath institute said, because of the colder weather and the end of the mosquito season.
Most people do not experience symptoms as a result of infection. Some 80% have no health problems at all while 20% have mild flu-like symptoms. However, in 1% of sufferers the virus can cause serious neurological problems, including encephalitis.
In southern Spain five people died of West Nile virus-induced encephalitis during an outbreak over the summer. The virus has been present in southern and central Europe for years and it was only a matter of time before it would come to western Europe, the RIVM said.