Is flu going around in the United Kingdom?
Influenza: no current data
UKHSA publishes this data in winter only. Last data: week of 20 Apr 2026. New season data expected from October.
Data window: Week 17 · Apr 20 – Apr 26 · Source: UKHSA
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Current activity
Source: UKHSA Dashboard, UKHSA Influenza, UKHSA RSV. Published weekly, about one week behind.
Frequently asked questions
When is flu season in the UK?
In the UK, flu activity typically begins rising in late autumn, climbs through December, and peaks between December and February before tailing off in March or April. The precise timing shifts year to year with the circulating influenza subtypes and population immunity. The UK Health Security Agency (UKHSA) tracks the curve each week and signals when activity enters elevated ranges, though intensity and duration vary considerably between seasons.
How does the UK classify the severity of a flu season?
UKHSA publishes a weekly national influenza and COVID-19 surveillance report and runs the UKHSA Dashboard, which together describe activity in qualitative bands from baseline to very high. Indicators include GP in-hours consultations via the Royal College of General Practitioners (RCGP) sentinel network, hospital admissions, ICU admissions, and laboratory-confirmed positivity. A season is considered severe once several indicators cross defined thresholds at the same time.
How is flu surveillance actually done in the UK?
UKHSA combines several data streams. Sentinel GP practices in the RCGP network record respiratory consultations and submit swabs for virological testing. Hospital surveillance through the Severe Acute Respiratory Infection (SARI-Watch) system captures admissions and critical care. The DataMart system provides laboratory-confirmed case numbers from NHS trusts. These feeds update weekly and are published on the UKHSA Dashboard alongside other respiratory pathogens.
Should I get the NHS flu vaccine?
The NHS offers a free annual flu vaccine to eligible groups including adults aged 65 and over, pregnant women, people with certain long-term health conditions, carers, frontline health and social care workers, and children from age two upwards. Uptake data is published by UKHSA each season. Vaccination remains the most effective single measure for reducing the risk of severe flu and the indirect burden on NHS winter capacity.
How does this year's UK flu season compare to previous ones?
Each season is shaped by the dominant subtype (influenza A(H3N2), A(H1N1)pdm09, or B) and by residual immunity from recent years. UKHSA reports plot current activity against historic thresholds, so it is possible to see whether the curve is running above or below the recent five-year average. Some seasons begin early and peak quickly; others are prolonged and moderate. No two winters produce the same pattern.