West Nile virus infects 44 people in the Netherlands this year
RIVM reports five deaths and says the virus is now circulating in several Dutch provinces.
This year, 44 people in the Netherlands have been infected with West Nile virus, RIVM reports. Five patients have died; at the same time, the institute says the risk to the public remains small and the mosquito season is nearly over.
RIVM recorded the 44 Dutch infections up to and including 23 September. The patients contracted the virus in Zuid-Holland, Utrecht, Noord-Holland, Noord-Brabant, Gelderland and Overijssel. In most cases, the infection was diagnosed after the patients had been admitted to hospital with symptoms. Since the previous update, 16 new cases have been reported; one of those patients died.
West Nile virus is spread by infected mosquitoes. Birds are an important reservoir: mosquitoes can pick up the virus when they bite an infected bird and then transmit it to other animals or people. RIVM also reports 136 infected horses, 171 birds that tested positive and four positive mosquito pools in the Netherlands.
The Dutch figures are part of a broader European development. The weekly tally by the European Centre for Disease Prevention and Control stood at 1,569 locally acquired human infections in 16 countries on 23 September. Public overviews may differ by a few cases because of different reference dates and definitions, but the European tally is around 1,600.
According to RIVM, the chance of being bitten by an infected mosquito and becoming ill in the Netherlands remains small. The institute points out that the season in which mosquitoes spread widely is nearly over. Most infections cause no symptoms or only mild symptoms, but a small proportion can be more serious. The figures say nothing about the individual risk to any specific person.
The situation is being monitored by, among others, RIVM, the Netherlands Food and Consumer Product Safety Authority, the municipal health services (GGD’en), Erasmus MC, Wageningen Bioveterinary Research, the Animal Health Service and Sanquin. According to the organisations involved, the current reports are mainly a signal for surveillance among people, animals, birds and mosquitoes; they are not a reason for general alarm.
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The key figures were checked directly against RIVM and the ECDC weekly tally. The text clearly distinguishes between Dutch reports, European tallies and the general risk.
- confirmed In the Netherlands, 44 human West Nile virus infections had been reported up to and including 23 September 2026. — RIVM table and update of 24 September 2026. source
- confirmed Five patients died in the Netherlands in 2026. — RIVM reports five deaths in 2026. source
- confirmed The Netherlands reported 136 infected horses, 171 infected birds and four positive mosquito pools. — RIVM overview as at 23 September 2026. source
- confirmed In Europe, 1,569 locally acquired human cases had been reported in 16 countries on 23 September. — ECDC weekly report. source
- confirmed RIVM assesses the general risk in the Netherlands as low. — RIVM describes the risk as low and the season as nearly over. source
Editor's note
The Dutch figures are based on RIVM data up to and including 23 September 2026. Public European tallies differ slightly because of the reference date and definition; the European scale has therefore been rounded.Sources
- Actuele informatie over westnijlkoorts — RIVM
- Surveillance of West Nile Virus infections in humans in Europe — ECDC
- West Nile virus in the Netherlands — NaTHNaC / TravelHealthPro
More on this in Dutch media
- RTL Nieuws — „westnijlvirus gezondheid”
- NOS — „westnijlvirus gezondheid”
- Het Parool — „westnijlvirus gezondheid”