Recent Weekly Surveillance Data on Winter Viruses in the UK

This weekly bulletin consolidates the most recent surveillance data alongside essential public health recommendations regarding influenza, COVID-19, Respiratory Syncytial Virus (RSV), and other viral infections.

Recent Surveillance Update

In the week from 5 to 11 October 2026, the trends for respiratory viruses were as follows:

• Influenza activity remained stable, circulating at baseline levels, with some indicators reflecting a reduction in activity among young adults.
• COVID-19 activity displayed mixed trends, continuing to circulate at low levels.
• Respiratory Syncytial Virus (RSV) activity saw an increase but is still circulating at baseline levels.

The weekly reports detailing flu, COVID-19, and RSV surveillance, along with the national reports on norovirus and rotavirus for the 2026 to 2027 season, are published regularly.

Influenza Surveillance Insights

During week 41 (5 to 11 October 2026), the surveillance data indicated:

• Influenza activity maintained its stability, with a positivity rate from laboratory surveillance at 6.0%, slightly down from 6.2% the previous week.
• The overall hospitalisation rate for flu remained unchanged at 1.88 per 100,000, consistent with the previous week.

COVID-19 Activity Overview

The COVID-19 surveillance data for the same week revealed:

• COVID-19 activity showed a mix of trends, sustaining circulation at low levels.
• The positivity rate for COVID-19 from lab surveillance was stable at 8.8%, down from 9% the prior week.
• Hospitalisations for COVID-19 rose to 2.46 per 100,000, compared to 2.13 the previous week.
• Admissions to intensive care/high dependency units remained low at 0.06 per 100,000, unchanged from the previous week.

RSV Surveillance Update

Regarding Respiratory Syncytial Virus (RSV) during the same period:

• RSV activity increased and is circulating at baseline levels, with positivity from lab surveillance rising to 1% from 0.4% the previous week.
• The weekly hospital admission rate for RSV also increased to 0.23 per 100,000 from 0.13 per 100,000.

Norovirus and Rotavirus Insights

Between weeks 40 and 41 (28 September to 11 October 2026), norovirus activity remained within expected seasonal levels:

• Laboratory reports for norovirus during this period were 18.6% lower than the five-season average.
• Rotavirus activity was 19.7% higher than the five-season average and remained within expected levels.
• Norovirus outbreaks reported to the Hospital Norovirus Outbreak Reporting System (HNORS) since the start of the 2025/2026 season are 25.4% lower than the five-season average.

To date in the 2025/2026 season, 87.2% of characterised samples were identified as norovirus genogroup 2 (GII), with GII.4 being the most frequent genotype at 24.6%.

Guidance on Managing Norovirus Infections

Symptoms of norovirus include nausea, vomiting, and diarrhoea, but may also present with a high temperature, abdominal pain, and aching limbs. Infections can lead to dehydration, particularly in vulnerable populations such as young children and the elderly. It is crucial to stay hydrated if ill.

Preventative measures can significantly mitigate the spread of norovirus. Regular handwashing with soap and warm water, alongside the use of bleach-based cleaning products, is essential. Alcohol-based hand sanitisers are ineffective against norovirus and should not be solely relied upon.

Individuals experiencing diarrhoea and vomiting should refrain from returning to work, school, or nursery until 48 hours after symptoms cease and should avoid preparing food for others during this time. Furthermore, it is advisable to avoid visiting hospitals and care homes to prevent transmitting the infection to those most at risk.