Weekly UKHSA report for the 2025/26 season, monitoring respiratory viruses as people are encouraged to take simple steps to protect themselves
Flu levels are beginning to stabilise for the first time this season, according to the latest surveillance data from the UK Health Security Agency (UKHSA). After an early start to the season and a sharp spike in recent weeks, the flu positivity rate is starting to decrease.
These are encouraging signals but it’s too early to say if flu has peaked this season and UKHSA is encouraging everyone to continue following good hygiene measures, with limited time now left to get a flu vaccine ahead of the Christmas and New Year period.
Flu is an unpredictable virus and while there is currently evidence that it is plateauing, the flu season is not yet over with the virus previously peaking well into January and February. Vaccination helps provide the best protection against severe illness and hospitalisation for those at higher risk, so getting vaccinated now will help to protect against flu viruses that may circulate later in the winter months.
There are simple measures that can be taken to help reduce the spread of flu this winter. Washing your hands regularly, making sure indoor spaces are well ventilated and if you have symptoms, stay home where possible. If you need to go out, consider wearing a face covering, particularly if visiting vulnerable people.
Those who are eligible for the flu vaccine are at most risk of serious complications from flu. This includes everyone over 65, those who are pregnant, young infants and those with certain long-term health conditions.
For children who missed out on their school immunisation programme, parents are reminded that they can still get them vaccinated in local community clinics. Pregnant women can also get vaccinated through maternity services.
Dr Alex Allen, Consultant Epidemiologist at UKHSA: “With Christmas just around the corner, it’s reassuring to see that flu levels are now starting to stabilise, but flu is notoriously unpredictable and can bounce back and peak a second time in the new year and so we’re urging people to continue taking sensible steps over the festive period to help stop the spread.
“There are simple steps we can all take to protect one another when mixing indoors. If you have flu or COVID-19 symptoms, including a high temperature, cough and feeling tired or achy, you should try to minimise contact with others, especially those more vulnerable.
“Washing hands regularly and ensuring indoor spaces are well ventilated helps and we advise those who have symptoms and need to go out, to consider wearing a face covering.
“For anyone eligible who is still not vaccinated, it’s not too late to get protected for the rest of the winter, but time is running out.
“Please make an appointment as soon as you can as vaccination can make all the difference in preventing severe illness and hospitalisation. By continuing to take these precautions, we can all do our bit to reduce the chances of another spike.”
In the week between 8 and 14 December 2025:
- influenza activity is stabilising in most indicators but still circulating at medium levels
- COVID-19 activity remained stable and is at baseline levels
- respiratory syncytial virus (RSV) activity showed mixed trends and is circulating at medium levels
The flu, COVID-19 and RSV surveillance report and the national norovirus and rotavirus surveillance reports: 2025 to 2026 season are published weekly.
Flu surveillance data for week 49 (8 to 14 December)
In week 49:
- flu activity is stabilising in most indicators but still circulating at medium levels
- flu positivity remained stable with a weekly mean positivity rate of 20.7% compared with 21% in the previous week. Positivity started to decrease in the later days of the week
- overall, flu hospitalisations were stabilising at 10.32 per 100,000 compared with 10.19 per 100,000 in the previous week
For the 2025-26 season’s vaccination programme, children and pregnant women have been eligible since 1 September, with other groups eligible from 1 October.
Up to the end of week 50 (14 December), vaccine uptake stands at:
- 38.6% in those aged under 65 years with one or more long term health conditions
- 36.5% in all pregnant women
- 72.8% in all those aged over 65 years
- 42.1% in children aged 2 years and 43.1% in children aged 3 years
Respiratory Syncytial Virus (RSV) surveillance data for week 49 (8 to 14 December)
In week 49:
- RSV activity showed mixed trends and is circulating at medium levels
- the overall weekly hospital admission rate for RSV was increasing at 3.70 per 100,000 compared with 3.35 per 100,000 in the previous week
- emergency department attendances for acute bronchiolitis increased
COVID-19 surveillance data for week 49 (8 to 14 December)
In week 49:
- COVID-19 activity remained stable and is at baseline levels
- COVID-19 positivity decreased slightly to 1.9% from 2.1% in the previous week
- COVID-19 hospitalisations were decreasing slightly at 1.02 per 100,000 compared with 1.10 per 100,000 in the previous week
- COVID-19 ICU admissions remained low at 0.05 per 100,000 compared with 0.03 per 100,000 in the previous week
Norovirus surveillance data between weeks 49 to 50 (1 December to 14 December 2025)
In week 49:
- norovirus activity has increased in recent weeks but remains within expected levels
- total norovirus laboratory reports between weeks 49 and 50 of 2025 were comparable to the 5-season average (4.9% lower) for the same 2-week period
- overall, norovirus laboratory reports between weeks 49 and 50 were 29.8% higher than during the previous 2-week period
- the rate of norovirus reports has started to increase in individuals aged 65 years and over and is now comparable to the reporting rate among individuals aged 0 to 4 years
- total rotavirus laboratory reports between weeks 49 and 50 of 2025 were comparable to the 5-season average (2.0% lower) for the same 2-week period
- the number of norovirus outbreaks reported to the Hospital Norovirus Outbreak Reporting System (HNORS) since the start of the 2025/2026 season is 48.5% lower than the 5-season average
- during the 2025/2026 season to date, the majority (83.3%) of samples characterised were norovirus genogroup 2 (GII), of which the most frequent genotype identified was GII.4 (31.1%)
- in recent weeks GII.4 has emerged as the predominant genotype and detections of GII.17 have decreased
Amy Douglas, Lead Epidemiologist at UKHSA, said: Norovirus has increased recently but remains within expected levels. With the festive season upon us, it’s important to remember the simple steps we can take to prevent the spread of norovirus.
“At the moment, the highest rate of cases are in children and people aged over 65. If your child has any symptoms, keep them off school or nursery until 48 hours after their symptoms stop. If you’re unwell, don’t visit hospitals and care homes to prevent spreading the infection to older and vulnerable people and don’t go to work or prepare food for others until 48 hours after your symptoms end.
“Washing your hands with soap and warm water and using bleach-based products to clean surfaces will also help stop infections from spreading. Hand sanitiser does not kill norovirus, so don’t rely on it alone.”