Respiratory illness in the Netherlands
The three major respiratory pathogens side by side — influenza, COVID-19 and RSV — based on ECDC ERVISS weekly data from NIVEL + RIVM.
Current situation: Influenza
In week 15 of 2026, activity of influenza (seasonal flu) in the Netherlands is low. The trend — derived from clinical surveillance — is rising. A clear upward movement has emerged over the past few weeks.
The classification is based on the ECDC ERVISS weekly reports, drawing on NIVEL primary care surveillance and virological data from RIVM (note that some indicators reflect influenza-like illness consultation rates only). Seasonally, infection waves in the Netherlands typically peak between January and March; activity is usually markedly lower during the summer months. How severe a given season becomes depends on the circulating virus variant and the population's immune status, among other factors.
Current situation: COVID-19
In week 15 of 2026, activity of COVID-19 in the Netherlands is low. The trend — derived from clinical surveillance — is stable.
The classification is based on the ECDC ERVISS weekly reports, drawing on COVID-19 indicators from NIVEL primary care surveillance and RIVM virological data (note that some indicators reflect ILI consultation rates only). Seasonally, infection waves in the Netherlands typically peak during winter, with occasional summer waves driven by new variants; activity is usually markedly lower in late spring between waves. How severe a given season becomes depends on the circulating virus variant and the population's immune status, among other factors.
Current situation: RSV
In week 15 of 2026, activity of respiratory syncytial virus (RSV) in the Netherlands is low. The trend — derived from clinical surveillance — is falling. Over a four-week comparison, a clear decline is visible.
The classification is based on the ECDC ERVISS weekly reports, drawing on RSV indicators from NIVEL primary care surveillance and RIVM virological data (note that ECDC coverage of RSV positivity can be limited for the Netherlands). Seasonally, infection waves in the Netherlands typically peak between December and February; activity is usually markedly lower in spring and summer. How severe a given season becomes depends on the circulating virus variant and the population's immune status, among other factors.
Data sources and methodology
The current picture for the Netherlands is built on the European Respiratory Virus Surveillance Summary (ERVISS), published weekly by the European Centre for Disease Prevention and Control (ECDC). NIVEL together with RIVM is the national public-health authority that feeds ERVISS with sentinel primary care and virology data.
ECDC ERVISS
ERVISS is ECDC's weekly pan-European surveillance summary for influenza, SARS-CoV-2 and RSV. National authorities — in the Netherlands's case NIVEL together with RIVM — submit harmonised indicators every week, which ECDC publishes in a standardised dataset on Thursdays. Using ERVISS rather than each country's native portal ensures cross-country comparability.
ILI / ARI consultation rates and positivity
NIVEL together with RIVM operates a sentinel network of general practices that report weekly rates of patients consulting for influenza-like illness (ILI) or acute respiratory infection (ARI). A subset of patients is swabbed and tested by reference laboratories, producing pathogen-specific positivity rates for flu, SARS-CoV-2 and RSV.
Why this source
Combining consultation incidence with virological positivity yields a pathogen-specific weekly incidence signal (ILI × positivity / 100). This is the standard European methodology and provides a more robust view than either indicator alone — consultation rates capture illness burden, positivity confirms which pathogen is driving it.
Qualitative classification
The “low”, “moderate” and “high” categories follow seasonal reference values and epidemiological thresholds calibrated to match our classifications for other countries. The ILI × positivity / 100 product is scaled to comparable thresholds using a divisor of 3, which aligns European sentinel peaks with the consultation-equivalent scale used elsewhere. Data refreshes weekly when ECDC publishes the latest ERVISS update, typically on Thursdays.
Frequently asked questions
How is overall respiratory-illness activity tracked in the Netherlands?
RIVM publishes a weekly respiratory-virus surveillance report covering flu, COVID-19, RSV, and other pathogens, drawing on Nivel sentinel GP data, virological testing at Erasmus MC and RIVM, hospital admission data, and wastewater measurements. Dutch data also feeds the ECDC ERVISS platform. On infectrisk.com we condense this into a qualitative low/moderate/high classification.
Did the Netherlands experience a “tripledemic”?
“Tripledemic” is a media label for the simultaneous winter circulation of flu, COVID-19, and RSV. The Netherlands saw clear co-circulation of all three pathogens in the 2022–2023 season, with noticeable pressure on paediatric care driven by RSV and on adult acute care. Co-circulation has continued in subsequent winters, though the relative intensity of each pathogen varies.
Why do respiratory illnesses peak in a Dutch winter?
The drivers line up in every temperate country. Many respiratory viruses remain stable longer in cold, dry indoor air, heated homes and offices lower humidity in ways that weaken airway defence, and people mix indoors more during winter. Schools and end-of-year gatherings accelerate transmission just as seasonal immunity is at its lowest. The Dutch peak typically sits a little later than the broader European average.
What is “immune debt”?
“Immune debt” describes how, after prolonged low circulation of a pathogen — for instance during strict COVID-19 measures — population-level immunity gradually declines and subsequent seasons can hit harder. The Netherlands' post-pandemic RSV and flu seasons showed patterns consistent with this effect, with unusually early or intense paediatric RSV activity. It is a temporary catch-up phenomenon, not a permanent immune change.
How does RIVM decide that activity is “high”?
RIVM uses thresholds derived from historical surveillance data. Current sentinel incidence, hospitalisations, positivity rates, and wastewater signals are compared against baselines from past non-epidemic weeks and against severe-season reference points. When several indicators cross into elevated bands at the same time, the weekly bulletin classifies activity as high, using the same framework that structures the Netherlands' ECDC ERVISS contribution.
Want the actual numbers?
You'll find them in the app.
Here you only see the trend. In the app: exact incidence rates, “X out of 100 people infectious”, your personal risk based on age and pre-existing conditions, wastewater trends, 36 countries, home-screen widget.
