West Nile virus: 16 new patients, fifth death
The RIVM reports 44 infections in the Netherlands and five deaths since the start of 2026.
Since last week’s update, sixteen new patients with West Nile virus have been reported in the Netherlands. One of them has died, bringing the total number of reported deaths in 2026 to five.
The RIVM reports that the number of confirmed human infections has risen from 28 to 44. According to the institute, the new patients contracted the virus through the bite of an infected mosquito. The infections were confirmed in South Holland, Utrecht, North Holland, North Brabant, Gelderland and Overijssel.
In most patients, the virus was detected after they had been admitted to hospital with symptoms. The RIVM stresses that the figures represent confirmed reports only. As many infections cause no symptoms or only mild symptoms, the actual number of infections may be higher.
The virus is spread by common house mosquitoes that have previously fed on infected birds. People and horses can become ill, but normally do not pass the virus on. Transmission through blood products is exceptional; following earlier findings, Sanquin screens donations from Dutch risk areas.
The number of reports among animals is also rising. The NVWA reports 136 horses that tested positive in 2026. In addition, 171 birds and four mosquito pools tested positive. The figures show that the virus is circulating in various parts of the Netherlands, but do not directly indicate how high the risk is for an individual resident.
According to the RIVM, around 80 per cent of infected people develop no symptoms. A smaller proportion develop flu-like symptoms, while around 1 per cent develop serious neurological symptoms. The institute does not advise the general public to undergo any specific treatment, but continues to monitor the spread together with, among others, the NVWA, Sanquin and research institutions.
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The figures and geographical spread come from the current RIVM table. The text clearly distinguishes between confirmed reports, the presumed actual spread and the individual health risk.
- confirmed Since 17 September, sixteen new human patients have been reported, bringing the total to 44. — This is stated in the RIVM update of 24 September 2026. source
- confirmed Five patients with a West Nile virus infection have died in 2026. — The RIVM reports five deaths. source
- confirmed In 2026, 136 horses, 171 birds and four mosquito pools were reported as testing positive. — These totals appear in the current RIVM table. source
- confirmed Sanquin screens blood donations from Dutch risk areas. — Sanquin describes the additional screening and the designated risk areas. source
Editor's note
The current figures have been taken directly from the RIVM update of 24 September. The RIVM makes no statements about the identities of deceased patients; the text therefore contains no personal data.Sources
More on this in Dutch media
- AD — „westnijlvirus westnijlkoorts”
- de Volkskrant — „westnijlvirus westnijlkoorts”
- RTL Nieuws — „westnijlvirus westnijlkoorts”