The respiratory syncytial virus (RSV) season has started, according to the latest respiratory surveillance data from the UK Health Security Agency (UKHSA). While the flu season started earlier, levels of RSV have been lower until recently, with the latest data showing a further increase in positive tests and hospital admissions, which is later than seen in previous years.
RSV infects around 90% of children within the first years of life and while it typically causes mild, cold-like symptoms, it can also lead to severe lung infections like pneumonia and infant bronchiolitis in some cases and is the leading cause of infant mortality globally.
Pregnant women are offered the vaccine at 28 weeks and it is recommended during every pregnancy to help provide the best protection for newborn babies. RSV also impacts older adults and can cause severe illness, which is why those aged 75 to 79 and who turned 80 years old after 1 September 2024 are also offered the vaccine.
Flu continues to circulate at low levels and it’s particularly important that eligible groups ensure they take up the offer of vaccination to help protect themselves as we head into the festive season. From this weekend, NHS teams across the country are ramping up their winter flu vaccine offer by hosting pop-up clinics across shopping centres, high streets, football clubs and soft play areas.
In the week between 10 and 16 November 2025:
- influenza activity showed mixed trends and continues to circulate at low levels after an unusually early start to the flu season
- COVID-19 activity decreased and is at baseline levels
- respiratory syncytial virus (RSV) activity increased and is now circulating at low levels
The flu, COVID-19 and RSV surveillance report and the national norovirus and rotavirus surveillance reports: 2025 to 2026 season are published weekly.
The respiratory syncytial virus (RSV) surveillance data for week 45 (10 to 16 November) included:
- RSV activity increased and is now circulating at low levels; this is a later start to the season than usually expected
- RSV positivity increased to 4% compared with 2.8% in the previous week
- emergency department attendances for acute bronchiolitis increased
- the overall weekly hospital admission rate for RSV was increasing at 1.79 per 100,000 compared with 1.33 per 100,000 in the previous week
Flu surveillance data for week 45 (10 to 16 November) included:
- influenza activity showed mixed trends and continues to circulate at low levels after an unusually early start to the flu season
- flu positivity decreased to 11.1% compared with 11.7% in the previous week
- overall, flu hospitalisations were decreasing slightly at 3.37 per 100,000 from 3.68 per 100,000 in the previous week
For the 2025 to 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 46 (9 November), vaccine uptake stands at:
- 33.5% in those aged under 65 years with one or more long term health conditions
- 32.8% in all pregnant women
- 67.8% in all those aged over 65 years
- 38.5% in children aged 2 years and 38.8% in children aged 3 years
COVID-19 surveillance data for week 45 (10 to 16 November) included:
- COVID-19 activity decreased and is at baseline levels
- COVID-19 positivity decreased to 3.3% from 4.7% in the previous week
- COVID-19 hospitalisations were decreasing at 1.08 per 100,000 compared with 1.80 per 100,000 in the previous week
- COVID-19 ICU admissions remained low at 0.04 per 100,000 compared with 0.08 per 100,000 in the previous week
- there were 9 COVID-19 acute respiratory incidents reported in total, with 6 incidents in care homes, 2 incidents in educational settings and 1 incident in hospital
- those aged 85 years and over had the highest hospital admission rate, which decreased to 10.97 per 100,000 compared with 17.50 per 100,000 in the previous week
Dr Alex Allen, Consultant Epidemiologist at UKHSA, said: "This week’s data shows how respiratory virus seasonal trends can vary from year to year, with RSV starting later than expected and flu starting over a month earlier. Despite our virus surveillance showing a mixed picture of activity for flu, we still expect to see further increases as we head into the colder winter months."
