Respiratory season
Influenza and RSV test positivity each week, as published by each country's public health agency. Data as of 18 September 2026.
influenza 2024–25influenza 2025–26RSV 2024–25RSV 2025–26weeks the source calls incomplete
England
data to 6 Sep 2026UK Health Security Agency: the share of people tested by PCR who had a positive result in the week (Monday to Sunday), by specimen date, from all PCR testing, England only (UKHSA publishes no UK figure); reported weekly in autumn and winter and fortnightly in summer
Germany
data to 13 Sep 2026ECDC (ERVISS): the share of swabs from primary-care sentinel practices that tested positive, ISO weeks (Monday to Sunday); ECDC relays the national figures and revises them retrospectively
Netherlands
data to 13 Sep 2026ECDC (ERVISS): the share of swabs from primary-care sentinel practices that tested positive, ISO weeks (Monday to Sunday); ECDC relays the national figures and revises them retrospectively; few swabs are taken out of season
United States
data to 12 Sep 2026 (latest week incomplete)CDC: the share of specimens tested by clinical laboratories that were positive, MMWR weeks ending Saturday, national; unsmoothed weekly figures; NREVSS describes its latest RSV week as incomplete
| Country | Latest week ending | % positive | Week before | Change (points) | Tests that week | Source release |
|---|---|---|---|---|---|---|
| England, influenza | 6 Sep 2026 | 2.5 | 2.4 | +0.1 | ||
| England, RSV | 6 Sep 2026 | 0.1 | 0.1 | +0.0 | ||
| Germany, influenza | 13 Sep 2026 | 1.4 | 0.0 | +1.4 | 70 | 18 Sep 2026 |
| Germany, RSV | 13 Sep 2026 | 0.0 | 0.0 | +0.0 | 70 | 18 Sep 2026 |
| Netherlands, influenza | 13 Sep 2026 | 27.3 | 11.1 | +16.2 | 11 | 18 Sep 2026 |
| Netherlands, RSV | 13 Sep 2026 | 0.0 | 0.0 | +0.0 | 11 | 18 Sep 2026 |
| United States, influenza | 12 Sep 2026 | 1.8 | 1.4 | +0.4 | 28,999 | |
| United States, RSV† | 5 Sep 2026 | 0.5 | 0.4 | +0.1 | 36,606 |
Method note
This tracker shows, each week, the share of tests for influenza and for RSV that came back positive, exactly as each agency publishes it. Positivity is not the number of people infected: it depends on who is tested, how many and why. We do not adjust, smooth or model the figures.
The agencies test different groups, so compare the shape of each line through the season rather than its height against another country's. England's figures are UKHSA's: the share of people given a PCR test in the week who had a positive result, from all PCR testing, by specimen date. UKHSA publishes no figure for the United Kingdom as a whole. Germany's and the Netherlands' figures are the primary-care sentinel positivity that the national agencies report to ECDC and WHO Europe, published through ERVISS, the European respiratory virus surveillance summary: swabs taken from patients seen by a network of general practices. The United States' figures are CDC's: influenza from clinical laboratories and RSV from the national NREVSS network.
Out of season few swabs are taken, so a single positive can move the percentage a long way; the table shows how many tests stood behind the latest figure where the source gives it. Recent weeks change as results arrive: UKHSA flags weeks still within its reporting delay, and CDC describes the latest RSV week as incomplete, so those weeks are drawn dashed. ECDC revises the European figures retrospectively.
Japan publishes no weekly test positivity, so it is not included. Denmark is not included either: its figures come from Statens Serum Institut, whose terms do not allow them to be republished.
Every release collected is kept, so revisions to past weeks can be traced; the most recent are listed under Revisions below, and the JSON download holds the releases themselves.
Sources and licences
- England: UK Health Security Agency, UKHSA data dashboard, influenza and RSV testing positivity by week, England. Vintage used: the figures as retrieved on 11 Sep 2026 (the source gives no release date). the share of people tested by PCR who had a positive result in the week (Monday to Sunday), by specimen date, from all PCR testing, England only (UKHSA publishes no UK figure); reported weekly in autumn and winter and fortnightly in summer. Licence: Open Government Licence v3.0. Source: UK Health Security Agency, licensed under the Open Government Licence v3.0.
- Germany: ECDC and WHO Europe, European Respiratory Virus Surveillance Summary (ERVISS), primary-care sentinel test positivity. Vintage used: the release of 18 Sep 2026. the share of swabs from primary-care sentinel practices that tested positive, ISO weeks (Monday to Sunday); ECDC relays the national figures and revises them retrospectively. Licence: CC BY 4.0. Dataset provided by ECDC based on data provided by public health authorities, scientific institutes or health care providers in the relevant reporting countries and/or by WHO.
- Netherlands: ECDC and WHO Europe, European Respiratory Virus Surveillance Summary (ERVISS), primary-care sentinel test positivity. Vintage used: the release of 18 Sep 2026. the share of swabs from primary-care sentinel practices that tested positive, ISO weeks (Monday to Sunday); ECDC relays the national figures and revises them retrospectively; few swabs are taken out of season. Licence: CC BY 4.0. Dataset provided by ECDC based on data provided by public health authorities, scientific institutes or health care providers in the relevant reporting countries and/or by WHO.
- United States: CDC — influenza percent positive from clinical laboratories (WHO/NREVSS, FluView); RSV percent positive, NREVSS national (data.cdc.gov rgnm-fkqb). Vintage used: the figures as retrieved on 19 Sep 2026 (the source gives no release date). the share of specimens tested by clinical laboratories that were positive, MMWR weeks ending Saturday, national; unsmoothed weekly figures; NREVSS describes its latest RSV week as incomplete. Licence: Public domain (US Government work). Source: CDC. Use of this material does not imply endorsement by CDC.
Japan publishes no weekly test positivity for influenza or RSV in machine-readable form; its sentinel surveillance reports cases per reporting site, which is a different measure.
Denmark is not included. Its figures come from Statens Serum Institut, whose terms do not allow them to be republished.
Revisions
Changes a source has made to its own past figures since this tracker began collecting.
- 19 Sep 2026, United States, influenza: 6 earlier week(s) revised; the largest change was the week ending 2026-09-05, from 1.3 to 1.4.
- 19 Sep 2026, United States, RSV: 3 earlier week(s) revised; the largest change was the week ending 2026-09-05, from 0.5 to 0.5.
- 19 Sep 2026, Netherlands, influenza: 1 earlier week(s) revised; the largest change was the week ending 2026-09-06, from 0.0 to 11.1.
- 11 Sep 2026, United States, RSV: 3 earlier week(s) revised; the largest change was the week ending 2026-08-29, from 0.4 to 0.4.
Download
CSV of the whole series · JSON, with every release collected