Research and analysis

Surveillance of respiratory syncytial virus: winter 2024 to 2025

Published 31 July 2025

Main points

Disease pattern

In the 2024 to 2025 season:

• overall RSV activity across all nations started around week 42 2024 (week starting 14 October 2024), and peaked across nations around weeks 47 to 49 2024 (18 November to 8 December 2024), before steadily declining and reaching baseline activity around weeks 7 to 8 2025 (10 February to 23 February 2025)

• the timing of peak RSV activity was similar to the 2023 to 2024 season in England and Wales, and slightly later than in previous seasons in Scotland and Northern Ireland

Vaccine uptake

Vaccination programmes to protect against RSV began on 1 September 2024 in England, Wales, and Northern Ireland, and on 1 August 2024 in Scotland. Data from Northern Ireland was not available for this report.

In England:

• 58.9% of eligible older adults had received an RSV vaccine by the end of May 2025 (36.4% of older adults in the routine cohort, 62.4% of older adults in the catch-up cohorts)

• 42.8% of women giving birth between the start of the programme and February 2025 had received an RSV vaccine prior to birth (56.3% of women giving birth in February 2025 had received an RSV vaccine)

In Scotland:

• 70.6% of eligible older adults had received an RSV vaccine by 11 May 2025 (69.9% of older adults in the routine cohort, 70.7% of older adults in the catch-up cohorts)

• 49.6% of women giving birth since the start of the programme had received an RSV vaccine prior to birth, as of 11 May 2025

In Wales:

• 44.9% of eligible older adults had received an RSV vaccine by 27 May 2025 (29.7% of older adults in the routine cohort, 47.3% of older adults in the catch-up cohorts)

• 40.3% of women giving birth between the start of the programme and April 2025 had received an RSV vaccine prior to birth (42.0% of women giving birth in April 2025 had received an RSV vaccine)

Vaccination impact

Early vaccine impact analyses in England and Scotland indicated a reduction in expected RSV-related hospitalisation rates among eligible older adults aged 75 to 79-years-old.

• 33% (95% CI 23% to 39%) reduction in England

• 62% (95% CI 35% to 80%) reduction in Scotland

The difference in impact may reflect the difference in vaccination coverage between England and Scotland coming into the RSV season, noting the different programme start dates.

Community surveillance

Acute respiratory infection incidents

Health protection professionals in the national agencies are notified of potential public health incidents, including outbreaks affecting different institutions, which are investigated, risk assessed and managed. There is some variation in reporting and recording practices between settings and caution is advised in comparisons.

England

Information on acute respiratory infection (ARI) incidents is based on situations reported to UKHSA health protection teams (HPTs) and entered onto the Case and Incident Management System (CIMS).

These include confirmed outbreaks of ARI (2 or more laboratory-confirmed cases of SARS-CoV-2, influenza, RSV or other respiratory pathogens) linked to a particular setting, as well as situations where an outbreak is suspected. All suspected outbreaks are further investigated by the HPT in liaison with local partners. Respiratory sampling to identify the virus involved is encouraged, however where clinical-epidemiological risk assessment suggests a higher probability of influenza this may not be done, and influenza antiviral prophylaxis started empirically. Incident reports are manually reviewed during the data-cleaning process and assigned to a specific pathogen only if confirmation of a positive virological test can be identified.

Please note that prior to July 2024, ARI incidents were recorded in HPZone, a previous case and incident management system. From July to September 2024, HPTs transitioned to a new system, CIMS. Any interpretation of seasonal and temporal trends since 1 July 2024 should consider the likelihood of differences in reporting of ARI incidents due to this change.

In England, there was a total of 3,332 ARI incidents in closed settings reported between week 40 of 2024 and week 14 of 2025. Virological testing information was available for 2,246 (67.4%) incidents, of which 179 (8.0%) were due to RSV, 78 (3.5%) were due to multiple pathogens (at least one of which was RSV) and 1,989 incidents (88.6%) were due to other pathogens, including 1,261 influenza and 472 SARS-CoV-2. In 1,086 (32.6%) incidents, virological testing results were not available.

Of the incidents in which RSV was virologically confirmed, 224 (87.2%) were reported from care homes, 20 (7.8%) from educational settings, 11 (4.3%) from hospital settings, 0 from prisons and 2 (0.8%) from other settings (Table 1).

Table 1. The number of ARI incidents in England by institution and pathogen between week 40 2024 and week 14 2025

Setting	RSV	Mixed outbreak (with RSV present)	Other pathogens	Not available/tested	Total
Care home	151	73	1,632	964	2,820
Educational setting	15	5	72	91	183
Hospital	11	0	208	10	229
Prison	0	0	21	2	23
Other	2	0	56	19	77
Total	179	78	1,989	1,086	3,332

The highest weekly number RSV outbreaks was observed during week 1 2025. All reported RSV outbreaks in educational settings occurred between week 40 and week 50 2024 (Figure 1).

Figure 1. Number of RSV outbreaks by week and setting, 2024 to 2025 season, England [note 1]

Note 1: includes outbreaks of RSV as well as mixed outbreaks where at least one of the pathogens identified was RSV.

Scotland

In Scotland, outbreaks are defined where at least 2 cases (laboratory confirmed and/or suspected) of any ARI are detected within 48 hours in any setting. To be defined as an ARI outbreak, either the pathogen or the scenario entered onto HPZone must be clearly indicative of ARI as the type of outbreak. Where a pathogen is listed but the outbreak is not laboratory confirmed, or where the pathogen is unknown, these have been labelled “Not available/tested”.

Between week 40 2024 (week ending 9 October 2024) and week 14 2025 (week ending 6 April 2025) there were 22 confirmed RSV outbreaks, of which 21 occurred within care homes and one in hospital settings (Table 2).

Table 2. Number of ARI incidents by institution and pathogen, Scotland, 2024 to 2025 season

Setting	Respiratory syncytial virus (RSV)	Other pathogens	Not available/tested	Total
Hospital	1	2	1	4
Prison	0	3	1	4
Other	0	1	7	8
Educational setting	0	2	61	63
Care home	21	146	88	255
Total	22	154	158	334

Wales

In Wales, outbreaks are reported on the Tarian system.

There were a total of 121 ARI outbreaks reported between week 40 2024 and week 12 2025. Virological results indicated that 8 outbreaks were due to RSV. Six of which were in residential homes, one in a hospital setting and one in a school nursery day care setting. There were an additional 3 incidents reported that were confirmed influenza and RSV.

Northern Ireland

Suspected ARI incidents in different settings are notified to the Public Health Agency (PHA) Acute Response Duty Room and recorded in HPZone. A confirmed ARI outbreak can be defined as where there are 2 or more laboratory confirmed cases with onset within a 14 day period, where transmission within the same setting is considered the likely cause.

In Northern Ireland, there were a total of 199 confirmed ARI outbreaks reported to the PHA Acute Response Duty Room from week 40 2024 (week commencing 30 September 2024) to week 18 2025 (week commencing 28 April 2025). Of these, 7 were confirmed RSV outbreaks, all within residential/care home settings.

Primary care surveillance

General practice sentinel swabbing

RCGP sentinel swabbing scheme in England

Primary care surveillance is undertaken in collaboration with the Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC). More information on the methodology can be found in the RCGP methodology report.

A subset of the RCGP RSC network (around 300 GP practices) take part in weekly virology surveillance. Practices collect nasopharyngeal samples from patients presenting to their GP with symptoms of any ARI with an onset date within the last 10 days. The ARI diagnosis definition is subclassified into influenza-like illness (ILI), lower respiratory tract infections (LRTI), upper respiratory tract infections (URTI) and exacerbation of chronic lung disease (ECLD).

From week 15 2024 to week 14 2025, among all-age individuals with RSV infection, the most frequent coded ARI diagnosis was URTI, followed by LRTI and ILI (Figure 2).

Figure 2. Weekly number of RSV attendances by coded ARI in England, GP sentinel swabbing, 2024 to 2025 season

By age group, in those aged under 5 years with RSV, the most frequent coded ARI diagnosis was URTI, followed by LRTI and ILI (Figure 3). In those aged 75 years and over with RSV, the most frequent coded ARI was LRTI, followed by URTI and ILI (Figure 4).

Figure 3. Weekly number of RSV attendances by coded ARI in those aged under 5 years in England, GP sentinel swabbing, 2024 to 2025 season

Figure 4. Weekly number of RSV positive samples by coded ARI in those aged 75 and over in England, GP sentinel swabbing, 2024 to 2025 season

Between week 15 2024 and week 14 2025, a total of 24,442 samples were tested for RSV and 1,216 were positive for RSV (Figure 5). Among the positive sample for RSV, 46.5% were positive for RSV A and 54.5% were positive for RSV B. 12 samples tested positive for both RSV A and RSV B. Starting from week 48 2024, samples with more than 10 days between the sample collection date and the symptom onset date were excluded.

RSV positivity began to increase in week 42 2024, peaked at week 49 2024, and started to decrease from week 50 (Figure 6). RSV B was predominant from week 1 2025.

By age group, the highest RSV positivity was observed in children under 5 years. Positivity peaked at 53.1% in week 46. Among those aged 75 years and above, the highest RSV positivity rate was 18.5% reported in week 49. During the peak season, RSV A was predominant in those aged under 5 years, whereas RSV B was more commonly detected among those aged 75 years and above (Figure 7).

Figure 5. Weekly number of samples testing positive for RSV in England, GP sentinel swabbing scheme, 2024 to 2025 season

Figure 6. Weekly positivity for RSV, RSV A and RSV B in England, GP sentinel swabbing scheme, 2024 to 2025 season

Figure 7. Weekly positivity for RSV, RSV A and RSV B in those aged under 5 years and aged 75 years and above, GP sentinel swabbing scheme, 2024 to 2025 season

In the 2024 to 2025 season, the all-age primary care RSV attendances incidence proxy was similar to that observed in the 2023 to 2024 season (Figure 8). This is an experimental metric used as a proxy for the incidence of primary care RSV attendances per 100,000 population. This is a composite indicator calculated using the weekly ARI rate per 100,000 population multiplied by the weekly RSV positivity among the ARI presentations. The ARI rate is calculated within the wider RCGP RSC network of around 2,000 GP practices covering over 19 million registered patients of all ages across England. The RSV positivity is from a subset of the GP practices participate to the virology swabbing surveillance. This approach is described in the WHO pandemic influenza severity assessment (PISA) framework.

Figure 8. Primary care RSV attendances incidence rate per 100,000 all-age population (proxy) in England, GP sentinel swabbing

Scotland

Community Acute Respiratory Infection (CARI) surveillance is a sentinel community surveillance programme for a range of respiratory pathogens: SARS-CoV-2, influenza A and B, RSV, adenovirus, coronavirus (non-SARS CoV-2), human metapneumovirus, rhinovirus, parainfluenza and Mycoplasma pneumoniae. The programme is open to GP practices across all NHS Boards in Scotland. To become a sentinel site, GP practices voluntarily opt into the CARI programme. The number of participating practices and the number of practices returning samples each week can vary but is within a range of 100 to 150 practices typically covering 15 to 20% of the total population. Patients in the community who consult a sentinel GP practice with respiratory symptoms and who meet the case definition for ARI are recruited, consented, and tested for the CARI programme. Clinicians also complete a symptoms checklist. More information on the methodology can be found in the overview of the CARI surveillance system.

Between week 15 2024 and week 14 2025, a total of 28,916 CARI samples were tested for RSV, of which 1,379 (4.8%) were positive for RSV. There was co-detection of another pathogen in 400 of these samples.

RSV test positivity increased exponentially from week 41, peaked in week 49 at 18.8% and declined thereafter (Figure 9). The highest RSV positivity was observed in children under 5 years, peaking at 50.7% in week 45 (data not shown). The highest test positivity observed for those aged 75 years and over was in week 50 at 15.9% (data not shown).

Figure 9. Weekly percentage of tests positive for RSV through CARI by season, Scotland, 2022 to 2025

Wales

Virological surveillance samples are collected from individuals presenting with ILI, ARI, acute bronchitis or bronchiolitis symptoms at a network of 75 sentinel GPs across Wales. Surveillance samples are routinely tested for: influenza, SARS-CoV2, RSV, adenovirus, Mycoplasma pneumoniae, rhinovirus, parainfluenza, human metapneumovirus, human bocavirus, seasonal coronaviruses, enterovirus D-68 and other enteroviruses.

In Wales, 9,494 samples were received for testing from sentinel GP practices between week 40 2024 and week 12 2025. Of these, 633 specimens tested positive for RSV. Positivity began on increase in week 42 2024, and peaked in week 47 2024 (19.2%). Positivity decreased to baseline levels by week 4 2025 (Figure 10).

Figure 10. Weekly percentage of tests positive for RSV, Wales, 2024 to 2025

Northern Ireland

Community sentinel GP practices cover approximately 18% of the population of Northern Ireland. The programme tests for influenza A and B, RSV and SARS-CoV-2 through the opportunistic swabbing of patients who provide consent, and who attend (in person) with ILI, ARI or suspected COVID-19 symptoms.

A total of 1,155 swabs were received from week 40 (week commencing 30 September 2024) to week 18 (week commencing 28 April 2025). 442 specimens tested positive for influenza, followed by 65 for RSV and 22 for SARS-CoV-2. The highest number of positive RSV samples were in week 52 (week commencing 23 December 2024) (13.8%; 9 out of 65) and the majority of positive RSV samples (93.8%; 61 out of 65) were received between weeks 46 (week commencing 11 November 2024) and week 6 (week commencing 3 February 2025).

Figure 11. Weekly percentage of tests positive for RSV by season, Northern Ireland, 2022 to 2025

Secondary care surveillance

Syndromic surveillance

England

In England, national UKHSA real-time syndromic surveillance systems include emergency department (ED) attendances via the Emergency Department Syndromic Surveillance System (EDSSS).

Bronchiolitis is the main clinical presentation of infant RSV and RSV is the main causative pathogen of bronchiolitis. In ED surveillance it is grouped with bronchitis. The daily number of ED attendances for acute bronchiolitis or bronchitis began to increase from September 2024 onwards, peaked on 18 November 2025 (during week 47 2024), similar to the baseline expectation from historical data. Attendance levels remained elevated before decreasing from 2 December 2025 (week 49 2024) until 12 January 2025 (week 2 2025). The majority of ED acute bronchiolitis or bronchitis attendances were patients aged under 5 years, with most aged under one year (Figures 12 and 13).

Figure 12. Daily ED attendances for acute bronchiolitis or bronchitis in all ages, England, 2024 to 2025 season

Figure 13. Daily ED attendances for acute bronchiolitis or bronchitis by age group in children aged under 5 years, England, 2024 to 2025 season [note 2]

Note 2: scales vary in each graph to enable trend comparisons. The black line is the 7-day moving average adjusted for bank holidays.

Scotland

The General/Acute and Inpatient Day Case dataset (SMR01) collects episode-level data on hospital inpatient and day case discharges from acute specialities from hospitals in Scotland. Figure 14 presents the weekly number of patients admitted as an emergency to a hospital in Scotland with an International Classification of Diseases, Tenth Revision (ICD-10) code related to acute bronchiolitis in any of the condition fields, by season between 2021 and 2025.

Weekly admissions for acute bronchiolitis peaked in Scotland during week 47 (week commencing 17 November 2024) compared to week 46 in the previous 2 seasons. The peak weekly number of admissions in 2024 to 2025 is lower than the peak in 2023 to 2024, and higher than the peak in 2022 to 2023 (Figure 14).

Figure 14. Weekly admissions for acute bronchiolitis by season, Scotland, 2021 to 2025

RSV hospital admissions

England

UKHSA collates data on test-confirmed hospitalised RSV cases in England by level of care (admissions excluding Intensive Care or High Dependency Unit (ICU or HDU) and admissions to ICU or HDU) through the Severe Acute Respiratory Infection (SARI) Watch surveillance system. This is a sentinel system, with data collected by a small network of acute NHS trusts reporting voluntarily. Trusts submit weekly aggregate counts of new RSV admissions and these are summed and converted to rates per 100,000 by linking to catchment populations of participating trusts in that week. Please see Sources of surveillance data for influenza, COVID-19 and other respiratory viruses for additional details on SARI Watch data collections including RSV.

From the 2024 to 2025 season, surveillance of RSV commenced in week 36 to routinely capture early season activity, pausing earlier at week 14 due to substantial decreases in activity that typically occur by this time. In prior seasons, RSV surveillance operated routinely between week 40 and week 20 in the following year (except in 2023 to 2024 where surveillance paused at week 16). Analyses for the 2024 to 2025 season include data from the full reporting period (week 36 2024 to week 14 2025 inclusive). Where comparisons to previous seasons are presented, data from week 40 to week 14 inclusive is used. Note that SARI Watch data is based on test-confirmed RSV infections (presenting with a pneumonia, ARI or ILI) and therefore trends should be interpreted in the context of potentially changing testing practices and subsequent confirmation and reporting of cases.

Overall, hospital admissions excluding ICU or HDU

From week 36 2024 to week 14 2025, a total of 4,233 test confirmed RSV hospital admissions (excluding ICU or HDU) were reported by 21 participating trusts in the 31 week period. All 21 trusts participated for a minimum of 21 weeks this season.

There were 2,149 hospitalisations (excluding ICU or HDU) in children aged under 5 years reported by SARI Watch sentinel trusts in the same period. Of these, 58.8% (n=1,263) were in children aged under one year, including 879 cases aged 6 months or younger.

Cumulative rates from week 40 to week 14 are presented to allow for historical comparisons. These are based on a sum of weekly rates which take into account only trusts participating in that week. The cumulative rate for hospital admissions excluding ICU or HDU was 46.24 per 100,000 trust catchment population. This was higher than the cumulative admission rate of 34.48 per 100,000 in the 2023 to 2024 season and higher than a cumulative admission rate of 31.08 per 100,000 in the 2022 to 2023 season.

Summary of epidemic activity

The hospital admission rate (excluding ICU or HDU) peaked at 4.73 per 100,000 trust catchment population in week 48 2024 (Figure 15). In the 2023 to 2024 season the rate peaked at 3.66 per 100,000 in week 48 2023. In the 2022 to 2023 season this peaked at 2.87 in week 47 2022 (Figure 15).

The hospital admission rate (excluding ICU or HDU) was highest among those aged 5 years or under, peaking at 46.17 per 100,000 in week 48 2024 (Figures 16 and 17). Those aged 85 years or more had the next highest rate, peaking at 18.78 per 100,000 in week 51 2024 (Figures 16 and 17).

Figure 18 shows the weekly number of RSV admission by level of care for all ages combined. The case numbers for admissions excluding ICU or HDU peaked in week 48 2024 and the case numbers for admissions to ICU or HDU peaked at week 51 2024.

Figure 19 shows the number of hospitalised cases (excluding ICU or HDU) among children aged under 5 years stratified by 4 age groups: under 6 months, 6 to 11 months, one year and 2 to 4 years. The total number of cases aged under 5 years peaked in week 48 2024 (n=254). Please note that case numbers are small at the start and at the end of the season when viewing at granular age groups. For most weeks in the 2024 to 2025 season, the majority of the cases in the cohort aged under 5 years were aged under 6 months; this proportion peaking in week 2 2025 at 62.7% (n=32).

Figure 15. Weekly hospital admission (excluding ICU or HDU) rate for new RSV positive cases per 100,000 trust catchment population, England, reported through SARI-Watch sentinel surveillance

Figure 16. Weekly hospital admission (excluding ICU or HDU) rate for new RSV positive cases per 100,000 trust catchment population in those aged under 5 years, 75 to 84 years and 85 years and over, England, reported through SARI-Watch sentinel surveillance [note 3]

Note 3: Please note that the y-scale range is adjusted according to age group to allow seasonal trends to be visualised more clearly.

Figure 17. Weekly hospital admission (excluding ICU or HDU) rate for new RSV positive cases per 100,000 catchment population by age group, England, 2024 to 2025 season, reported through SARI Watch sentinel surveillance [note 4]

Note 4: the highlighted line corresponds to the age group in the subplot title, grey lines correspond to all other age groups.

Figure 18. Weekly count of hospital admissions of new RSV positive cases, England, 2024 to 2025 season, reported through SARI Watch sentinel surveillance by level of care [note 5]

Note 5: Please note that the number of admissions are based on data submitted by a small network of acute NHS trusts participating in SARI-Watch’s sentinel surveillance, hence do not represent the totality of RSV admissions in all NHS trusts in England.

Figure 19. Weekly count of hospital admissions (excluding ICU or HDU) of new RSV positive cases, in children aged under 6 months, 6 to 11 months, 1 year and 2 to 4 years, England, 2024 to 2025 season, reported through SARI Watch sentinel surveillance [note 6]

Note 6: Please note that the number of admissions are based on data submitted by a small network of acute NHS trusts participating in SARI-Watch’s sentinel surveillance, hence do not represent the totality of RSV admissions in those aged under 5 years in all NHS trusts in England.

Scotland

Patients admitted as an emergency to a hospital in Scotland with a recently confirmed positive RSV test are identified from Rapid Preliminary Inpatient Data (RAPID). RAPID is a daily submission of people who have been admitted to hospital in Scotland. The case definition includes patients admitted as an emergency to a medical speciality (excluding surgical and mental health specialities, and emergency admissions with patient injury codes) who have a positive RSV test result, taken within a period of between 14 days before the admission date and 2 days after the admission date.

The rate of hospital admission with an associated positive RSV test peaked at 7.05 per 100,000 population in week 47 2024. The peak was 8.09 per 100,000 in week 46 2023 in the 2023 to 2024 season, and 4.52 per 100,000 in week 48 2022 in the 2022 to 2023 season (Figure 20).

Figure 20. Weekly RSV hospital admission rate per 100,000 by season, Scotland, 2022 to 2025

Hospital admissions were highest among those aged 5 years or under, peaking at 312 in week 47 2024. Peak hospital admissions in the 75-to-84 and 85-plus age groups occurred later, in week 2 2025 and week 51 2024 respectively (Figure 21).

Figure 21. Weekly RSV hospital admissions by age group and season, Scotland, 2022 to 2025 [note 7]

Note 7: Scales vary in each graph to enable trend comparisons

Wales

Hospitalised RSV cases in Wales are identified by linking hospital admissions recorded in the Wales Patient Administration Systems (PAS) to laboratory test results using patient NHS number. Cases are defined as those admitted to hospital who tested positive for RSV within 28 days prior to admission or up to day 2 of an inpatient stay (where admission date is day 1).

A total of 1,166 hospitalised RSV cases were reported in Wales from week 40 2024 to week 12 2025. Hospital admissions started to increase in week 42 2024 and peaked in week 48 2024 at 104 admissions.

Figure 22. Weekly RSV hospital admissions by age group and season, Wales, 2022 to 2025 [note 8]

Note 8: Scales vary in each graph to enable trend comparisons

Northern Ireland

Community-acquired RSV admissions to hospitals are estimated by combining data from the Patient Administration System (PAS) and EPIC Encompass, with RSV test results from the Northern Ireland Health Analytics Platform (NIHAP). Cases are defined by a combination of an emergency admission associated with a positive RSV test between 7 days before and one day after admission. All trusts in Northern Ireland contribute to this data collection.

RSV admission activity increased from week 43 (week commencing 20 October 2024) showing 2 peaks in weeks 47 and 49 (week commencing 17 November and 1 December 2024, respectively) at 6.6 and 6.7 per 100,000 population, respectively before steadily declining to low levels (Figure 23). There was a total of 1,078 emergency admissions, with a cumulative admission rate of 56.1 per 100,000 population. The majority of RSV emergency admissions was reported in those aged under 5 years old (81.1%; 874 out of 1,078).

Figure 23. Weekly RSV hospital admission rate per 100,000 by season, Northern Ireland, 2021 to 2025

Figure 24. Weekly RSV hospital admission rate per 100,000 by season in those aged under 1 year, 1 to 4 years and 75 years and over, Northern Ireland, 2021 to 2025 [note 9]

Note 9: scales vary in each graph to enable trend comparisons

RSV ICU or HDU admissions

From week 36 2024 to week 14 2025 inclusive, there was a total of 277 RSV admissions to ICU or HDU reported by SARI Watch sentinel trusts based on all ages. Of these admissions, 214 were among those aged under 5 years. Among admissions in those aged under 5 years, 76.6% (n=164) were in children aged under 1 year, including 132 cases aged under 6 months.

Admission rates to ICU or HDU among children aged under 5 years in 2024 to 2025 and in previous seasons are presented in Figure 25. Weekly rates fluctuate due to small underlying numbers. The rate peaked at 4.44 per 100,000 in week 51 2024. By comparison, in the 2023 to 2024 season, this peaked at 7.01 per 100,000 in week 46 2023. In the 2022 to 2023 season, this peaked at 3.55 per 100,000 at week 47 2022.

Figure 25. Weekly admission rate to ICU or HDU in under 5 years for new RSV positive cases per 100,000 trust catchment population, England, reported through SARI-Watch sentinel surveillance

Scotland

Patients admitted to ICU/HDU with recently confirmed RSV are identified from the Scottish Intensive Care Society Audit Group (SICSAG) that collects detailed patient-level data on all patients in ICU/HDU across Scotland. All patients that are admitted to ICU/HDU with a positive RSV test result within a period of 14 days before the ICU/HDU admission date or 2 days after the ICU/HDU admission date are included.

From week 40 2024 to week 14 2025 inclusive, there was a total of 73 admissions to ICU or HDU with an associated positive RSV test. This is lower than the same period in the 2023 to 2024 and 2022 to 2023 seasons (Figure 26).

Figure 26. Weekly RSV admissions to ICU or HDU for RSV positive cases by season, Scotland, 2022 to 2025

ECMO

Extra-corporeal Membrane Oxygenation (ECMO)

Data from 7 Severe Failure Centres for adults in England and Scotland from week 40 2024 to week 14 2025 shows that there were 2 admissions for test confirmed RSV acute respiratory infection. Please refer to the Influenza in the UK, annual epidemiological report: 2024 to 25 for further details.

Laboratory surveillance

Respiratory Datamart, England

The Respiratory Datamart system began during the 2009 influenza pandemic to collate all laboratory testing information in England. It is now used as a sentinel laboratory surveillance tool, monitoring all major respiratory viruses in England. 14 laboratories in England, including 5 public health laboratories, 8 NHS hospital laboratories and a UKHSA national laboratory, reported data for this season. The majority of samples were received from hospitals.

RSV positivity peaked only once in week 48, reaching 15.6%, comparable to the previous season (14.1%). Raised activity above baseline (set using the moving epidemic method) lasted 9 weeks from week 44 to week 52. The overall seasonality of positivity resembles pre-COVID-19 pandemic patterns. Positivity by age group for the 2024 to 2025 season is shown in Figure 28, with highest positivity in those aged under 5 years old.

Figure 27. Weekly overall RSV swab percentage positivity through Respiratory DataMart by season, England

Figure 28. Respiratory DataMart weekly positivity (%) for RSV by age, England, 2024 to 2025

Scotland

All NHS laboratories in Scotland submit data for positive RSV tests via the Electronic Communication of Surveillance Scotland (ECOSS) database. As of the 2024 to 2025 season, data submitted by all NHS laboratories includes negative results for RSV. Tests, which have been taken as part of the CARI programme, are systematically excluded from all of the following ECOSS-derived figures.

Episodes are defined as positive laboratory confirmed RSV test, not occurring within 56 days of a previous positive result for the same pathogen. Test positivity is calculated as the number of samples associated with a positive test divided by the total number of samples for a given pathogen.

RSV cases peaked in week 51 (week commencing 16 December 2024). This is 5 weeks later than the peak observed during the 2023 to 2024 season, although the number of cases at the peak was similar in both seasons (Figure 29). RSV positivity peaked earlier, in week 47 (week commencing 17 November 2024) at 14.4% before declining thereafter (Figure 30). Overall RSV positivity showed an increased level of activity (above 5%) from week 43 (commencing 20 October 2024) to week 4 (week commencing 20 January 2025).

Figure 29. Weekly ECOSS RSV counts by season, Scotland, 2021 to 2025

Figure 30. Weekly ECOSS RSV positivity, Scotland, 2024 to 2025 season

Wales

Diagnostic virology results from Wales concern all test results in Wales present in the Datastore. These are from patients tested from non-sentinel settings. The vast majority of these patients are in hospital, with a small proportion from non-sentinel community sources.

Out of 29,704 samples tested between week 40 2024 and week 12 2025, 2,339 tested positive for RSV. Overall positivity started to increase in week 40 2024 and peaked in week 47 2024 at 17.6% (Figure 31).

Figure 31. Weekly percentage tests positive for RSV, Wales, 2024 to 2025

Northern Ireland

Results of all positive and negative RSV testing from the Regional Virus Laboratory (RVL) and all local laboratories are collated into the Northern Ireland Health Analytics platform (NIHAP). Microbiological surveillance is the monitoring of RSV from virology data collected from settings such as hospitals and GP surgeries. The majority of samples were received from hospitals.

Overall RSV positivity showed an increased level of activity (above 5%) from week 44 (commencing 27 October 2024) and peaked in week 47 (week commencing 17 November 2024) at 17.1% before declining thereafter. This is lower than the peak in the 2023 to 24 season, which was 18.3% in week 46 (week commencing 13 November 2023) (Figure 32).

Figure 32. Weekly percentage tests positive for RSV by season from NIHAP, Northern Ireland, 2021 to 2025

Figure 33. Weekly percentage tests positive for RSV by season and age group from NIHAP, Northern Ireland, 2021 to 2025 [note 10]

Note 10: scales vary in each graph to enable trend comparisons

Mortality

England

RSV-related deaths in children within each season were measured using positive RSV cases from SGSS and ONS all-cause mortality data. Laboratory confirmed RSV case records were linked to the deaths recorded in the NHS Spine using demographic batch service tracing as well as ONS all-cause mortality records to indicate where a case had died within 28 days of their earliest positive specimen within that season. ONS all-cause mortality data was also used to identify deaths where RSV was mentioned as a cause of death on an individual’s death certificate.

Between 6 October 2024 and 6 April 2025 (week 40 to week 14), an estimated 31 RSV-related deaths occurred in children under 18 years of age. For comparison, an estimated 20 paediatric RSV-related deaths were reported in the 2023 to 2024 season (1 October 2023 to 18 May 2024), and 29 deaths in the 2022 to 2023 season (2 October 2022 to 20 May 2023).

Please note that there are significant reporting lags in mortality data. At the time of publication, data is available only up to week 14 for the 2024 to 2025 season, whereas for previous seasons, data is available up to week 20. The date range refers to the date of death and includes individuals who tested positive for RSV up to 28 days prior. RSV-related deaths were identified using ICD-10 codes J121, J205, and J210.

Table 3. Estimated number of deaths associated with RSV in those aged under 18 years, England, 2022 to 2025

	2022 to 2023	2023 to 2024	2024 to 2025
Deaths with RSV mentioned on death certificate	18	15	19
Deaths within 28 days of a RSV positive	13	6	13
Total RSV related deaths	29	20	31

Vaccination

Maternal vaccine uptake

England

An RSV vaccination programme for pregnant women was introduced in England on 1 September 2024, to protect infants against severe RSV disease. Pregnant women become eligible as they reach 28 weeks gestation, remaining eligible until the end of the pregnancy. All women who were at least 28 weeks pregnant at the start of the programme on 1 September 2024 were eligible for a single dose of RSV vaccine.

In this report, the eligible population (denominator) for the maternal vaccination programme is defined as all identified women giving birth in a calendar month. The denominator is collected using the Maternity Services Data Set (MSDS), a patient-level data set from NHSE that captures activities carried out by maternity services. MSDS has a 3-month lag in reporting. RSV vaccination events are collected from the UKHSA’s Immunisation Information System (IIS), which captures denominator data and vaccination events across England, via the Data Provisioning Service (DPS) at NHS England (NHSE). IIS includes a patient-level data set of individuals eligible for primary care in England.

Vaccine uptake for each month is calculated as the number of women giving birth in that month who have received an RSV vaccine (numerator) divided by the denominator for that month. The maternal denominator was extracted from MSDS on 5 July 2025, which included February 2025 births, and linked to RSV vaccine records from IIS. Gestational age at vaccination was calculated using the gestational age at birth from MSDS records and the date of vaccine administration from IIS. Please note that this method of calculating vaccine uptake is different from that used in the monthly RSV maternal vaccination coverage reports published by UKHSA, which uses aggregate data from GP records.

Between 1 September 2024 and 28 February 2025, 42.8% of all women giving birth had received an RSV vaccine prior to delivery.

In each month since the start of the programme, RSV vaccine uptake in women giving birth has increased (Figure 34). Out of the women giving birth in February 2025, 56.3% had received an RSV vaccine. The average gestational age at vaccination has decreased as the programme has progressed. By December 2024, the majority of vaccinated women giving birth received their vaccine between 28 and 31 weeks gestation. This is because women eligible for vaccination at 28 weeks at the start of the programme would have given birth on average 3 months later. This is seen in the increasing size of the dark blue section of the columns, compared to the teal (32 to 36 weeks) and red (37 weeks and greater) in Figure 34.

Figure 34. RSV vaccine uptake for women giving birth in a given month by gestational age at vaccination, England

Overall, most regions shared a similar pattern of increasing monthly RSV vaccine uptake as the programme has progressed, although there is some month-on-month variation (Figure 35). There was also a similar increase in women giving birth receiving their vaccine earlier in pregnancy across all regions. There was appreciable variation in uptake between regions in women giving birth in February 2025, with the lowest uptake in London (46.5%) and the highest in the South West (65.4%).

Figure 35. RSV vaccine uptake for women giving birth in a given month by gestational age at vaccination and region, England

Scotland

On 1 August 2024 pregnant women in Scotland became eligible for RSV vaccination from 28 weeks of their pregnancy until the end of pregnancy.

The eligible population (denominator) is sourced from Scottish Linked Pregnancy and Baby Dataset (SLiPBD), and includes both ongoing pregnancies and live births. Vaccination events are recorded using the TURAS Vaccination Management Tool a web-based tool for Healthcare staff in Scotland to record real-time patient vaccination data at the point of care. Vaccination events are then stored in the National Clinical Data Store (NCDS) developed by NHS Education Scotland. Information on vaccine uptake for the RSV vaccine programme is available from the PHS Vaccination Surveillance Dashboard.

By 11 May 2025, RSV vaccine uptake in pregnancy over the entirety of the programme was 49.6%. Data includes both ongoing pregnancies and live births.

Wales

RSV vaccine uptake in women who have given birth is calculated using data in the Wales Maternity Indicators Delivery Dataset. The Wales Maternity Indicators Delivery Dataset contains data for women residing in all health board areas and uptake is calculated for women with delivery dates during the most recent month. RSV vaccination events are extracted from the Wales Immunisation System (WIS). More information on the methodology, as well as the latest uptake figures, can be found in the Immunisation surveillance reports published by Public Health Wales.

Overall, since the start of the programme on 1 September 2024, 40.3% of women who had given birth had received an RSV vaccine. Monthly RSV vaccine uptake has generally increased since the start of the programme, although there is some month-on-month variation (Figure 36). Out of the women giving birth in the most recent month for which data is available, April 2025, 42% had received an RSV vaccine.

Figure 36. RSV vaccine uptake in women giving birth by month, Wales

Northern Ireland

Data on RSV vaccine uptake in pregnant women in Northern Ireland will be available on the Public Health Agency website following the first full year of the programme.

Older adults vaccine uptake

England

Vaccination against RSV was introduced in England on 1 September 2024 as programmes for older adults and pregnant women. All adults turning 75-years-old on or after 1 September 2024 are eligible for the routine programme. In addition, there is a one-off catch-up offer for adults already aged 75 to 79-years-old at the start of the programme.

The eligible population for the older adult vaccination programme was extracted from IIS and linked to RSV vaccination events on 31 May 2025. Vaccine uptake is calculated as the number of eligible older adults who had received an RSV vaccine (numerator) divided by the total number eligible to receive the vaccine (denominator).

The 5 catch-up cohorts are defined by their birth year and age as of the programme start date on 1 September 2024. The routine cohort is defined as those turning 75 since the programme start date. As such, for this report, the routine cohort in England includes individuals born between 1 September 1949 and 31 May 1950. A more detailed breakdown of the older adults cohorts is presented in Table 4, along with their RSV vaccine uptake as of 31 May 2025.

By 31 May 2025, 58.9% of all eligible older adults in England had received an RSV vaccination. By 31 May 2025, 62.4% in the catch-up cohorts combined had received an RSV vaccination, compared to 36.4% in the routine cohort, although the routine cohort includes individuals who have only recently become eligible.

Table 4. RSV vaccine uptake in older adults cohorts by 31 May 2025, England

Cohort	Birth range of cohort	Age prior to start of programme	Vaccine uptake 31 May 2025
Routine cohort	1 September 1949 to 31 May 1950	74	36.4%
Catch-up cohort 1	1 September 1948 to 31 August 1949	75	61.2%
Catch-up cohort 2	1 September 1947 to 31 August 1948	76	61.9%
Catch-up cohort 3	1 September 1946 to 31 August 1947	77	62.9%
Catch-up cohort 4	1 September 1945 to 31 August 1946	78	63.1%
Catch-up cohort 5	1 September 1944 to 31 August 1945	79	63.2%

RSV vaccine uptake in the routine cohort, who continue to gain eligibility through the programme, remains lower compared to the catch-up cohorts, who were all eligible from the start of the programme (Figure 38). However, since week 6 2025, there has been a noticeable increase in the rate of vaccination among the routine cohort, when the NHS in England issued an additional round of immunisation reminders.

Figure 38. Cumulative RSV vaccine uptake in older adults cohorts on 31 May 2025, England

RSV vaccine uptake in older adults catch-up cohorts has followed a similar trend across 8 of the 9 regions in England, with London having a noticeably lower uptake than the rest of the country (Figure 39). By 31 May 2025, the region with the lowest RSV vaccine uptake in catch-up cohorts was London (47.5%), while the region with the highest uptake was the South East (66.9%).

Figure 39. Cumulative RSV vaccine uptake in older adults catch-up cohorts on 31 May 2025, by region, England

Scotland

From 1 August 2024, those who are turning 75 years old (by 31 July 2025) and those already aged 75 to 79 residing in Scotland were eligible for a free vaccine to protect them from RSV. Vaccination cohort sources are documented on each tab in the PHS Vaccination Surveillance Dashboard.

From 1 August 2024 to 11 May 2025, 69.9% of older adults turning 75 years old, and 70.7% of older adults already aged 75 to 79 in Scotland had received an RSV vaccination. Overall, 70.6% of eligible older adults in Scotland had received an RSV vaccination.

Wales

Vaccination data for older adults is sourced from WIS. RSV vaccine uptake is calculated for adults living and Wales resident as at 27 May 2025. More information on the methodology, as well as the latest uptake figures, can be found in the Immunisation surveillance reports published by Public Health Wales.

By 27 May 2025, 44.9% of all eligible older adults in Wales had received an RSV vaccination. Split by cohort, 29.7% of adults turning 75 (the routine cohort) and 47.3% of adults already aged 75 to 79 years at the start of the programme (the catch-up cohort) in Wales had received an RSV vaccine. RSV vaccine uptake in the routine cohort, who continue to gain eligibility through the programme, was greatest in those who have been eligible for longer (Figure 41).

Figure 40. Cumulative RSV vaccine uptake in older adults catch-up cohorts on 27 May 2025, Wales

Figure 41. RSV vaccine uptake in older adults routine cohort by month of birth, Wales

Northern Ireland

Data on RSV vaccine uptake in older adults in Northern Ireland will be available on the Public Health Agency website following the first full year of the programme.

Vaccine impact

England

The first analysis on the impact of the RSV vaccination programme in older adults in England was published in March 2025, using a Regression Discontinuity Design (RDD). A 30% reduction in RSV-associated hospitalisation in older adults eligible for the vaccine was found in comparison with those non-eligible, at a time when vaccine uptake was around 40%. A more recent analysis (included here) with data collected up to the end of the season (31 March 2025) now shows a reduction of 33%. While vaccine uptake is now higher there has been limited RSV transmission in February to March in line with seasonal norms.

There was a discontinuity in hospitalisation rates corresponding to a 33% reduction (95% CI 23% to 39%, p-value <0.0001) in those aged 75 to 79 and eligible for RSV vaccine.

Figure 42. Observed, modelled, and predicted RSV-associated hospital admission rates by age, England

The maternal RSV vaccine for infant protection is recommended in gestation week 28. This is around 12 weeks before the average birth, and around 18 weeks before the peak risk age for RSV, therefore the programme impacts are more lagged than the older adults’ programme. The maternal programme impact will be more clearly seen in the 2025 to 2026 season, after which an impact assessment will be published.

Scotland

The early impact of the RSV vaccination programme in the 2024 to 2025 season in Scotland was measured using a RDD study, which was published in March 2025. RSV related hospitalisation rates among individuals aged 75 to 79-years-old were compared with those in adjacent, non-vaccinated age groups (70 to 73-years-old, 80 to 84-years-old) in 2023 (pre-vaccination) and 2024 (post-vaccination) to see if there was a change in hospitalisation rates in those 74 to 79 years old post vaccination. The analysis was performed through the data linkage of RSV testing records from ECOSS and hospital admission records from the RAPID dataset. The analysis covered the period from 1 October 2024 to 8 December 2024.

Following introduction of the RSV vaccine, a 62.1% (95% CI 35.0% to 79.8%) reduction in RSV-related hospitalisations among the eligible age group was observed.

Figure 43. Observed, modelled and predicted rates of admissions to hospital due to RSV by age, Scotland: (left) pre-vaccination discontinuity between ages 74 to 79 shown for winter 2023, (right) post-vaccination discontinuity between ages 74 to 79 shown for winter 2024

Data sources and methodology

For additional information regarding data sources please refer to the data quality report for national respiratory virus surveillance.

Further details on the data and methods used for Scotland can be found in the Viral respiratory diseases (including influenza and COVID-19) in Scotland surveillance report.

Further details on the data from Wales informing this report are available in the weekly report.

Further information on the methods and caveats used for Northern Ireland can be found in the Respiratory surveillance report.

Further information and contact details

Feedback and contact information

To provide feedback and for all queries relating to this document, please contact respdsr.enquiries@ukhsa.gov.uk

Acknowledgements

Compiled by the RSV surveillance team, Immunisation and Vaccine-Preventable Diseases division, UK Health Security Agency with contributions from:

• Public Health Scotland

• Public Health Wales

• Public Health Agency, Northern Ireland

• Royal College of General Practitioners

• Real-time Syndromic Surveillance team, UK Health Security Agency