1 Summary

• Coverage of RSV vaccination in women who delivered during 2024/25 programme year was 31.5% (5,897 out of 18,706).
• Coverage was highest in women aged 35-39 years (37.8%).
• Coverage varied by Local Government District (LGD). Coverage was highest in Lisburn and Castlereagh (48.9%) and Ards and North Down (47.2%).
• Maternal RSV vaccination was associated with a significant reduction in RSV-related hospitalisations, with an overall vaccine effectiveness of 83.7% (95% CI: 67.9-92.4%) in vaccinated infants compared with unvaccinated infants.

2 RSV vaccination programme for infant protection

The respiratory syncytial virus (RSV) vaccination programme for pregnant women to provide infant protection was introduced in Northern Ireland on 1 September 2024. This report details vaccine coverage during the first year (2024/25) of the vaccination programme for pregnant women, from 1 September 2024 to 31 August 2025. Pregnant women were eligible from 28 weeks gestation and the programme was delivered by GP and Health and Social Care Trusts.

In 2024/25, 5,897 out of 18,706 women who delivered during the programme year received an RSV vaccine. RSV vaccination coverage of women who delivered during the 2024/25 programme was 31.5%. Vaccination coverage was lowest in women who delivered in September 2024 (3.4%). Coverage increased between September 2024 and December 2024 (3.4% to 34.2%). Coverage continued to increase from January 2025 with coverage highest in women who delivered during August 2025 (42.5%), Women who delivered earlier in the programme had less opportunity to receive an RSV vaccine as the vaccination programme was introduced for the first time on 1 September 2024 (Figure 2.1).

Figure 2.1: RSV vaccination coverage in women who delivered during the programme in Northern Ireland by month of delivery, 2024/25.

2.1 Vaccine coverage by age

RSV vaccination coverage in women who delivered during 2024/25 improved with increasing age (age at delivery) up to 35-39 years (37.8%). Coverage was lowest in mothers women under the age of 20 years and 20-24 years (17.1% and 18.1%, respectively) (Figure 2.2),

Figure 2.2: RSV vaccination coverage in women who delivered during the programme in Northern Ireland by age at delivery, 2024/25.

2.2 Vaccine coverage by Local Government District

Vaccination coverage of women who delivered during 2024/25 varied by Local Government District (LGD) of residence. Vaccination coverage was greatest in Lisburn and Castlereagh (48.9%) and Ards and North Down (47.2%). Coverage was lowest in Mid Ulster (20.9%) (Figure 2.3).

Figure 2.3: RSV vaccination coverage in women who delivered during the programme in Northern Ireland by Local Government District, 2024/25.

3 Vaccine effectiveness

Our analysis provides evidence that maternal RSV vaccination substantially reduces the risk of RSV-related hospital admission in infants, including those born preterm. Using a test-negative design adjusted for maternal age, epidemiological week, and Health and Social Care (HSC) Trust of maternal residence, we analysed infants aged 182 days or younger who were hospitalised between epidemiological Week 40 2024 and Week 13 2025 (30 September 2024 to 30 March 2025) in Northern Ireland and received an RSV RT-PCR test within 14 days before to 2 days after hospital admission (i.e., either a positive or negative laboratory result). The analysis was conducted using pseudonymised data.

Maternal RSV vaccination was associated with a significant reduction in RSV-related hospitalisations, with an overall VE of 83.7% (95% CI: 67.9-92.4%) in vaccinated infants compared with unvaccinated infants. Among preterm infants (<37 weeks’ gestation), vaccination was also highly effective, with a VE of 95.2% (95% CI: 28.4-100%). Infants whose mothers were vaccinated shortly before birth (0-13 days before birth) were less protected (VE = 62.6%; 95% CI: -35.1-90.9%), reinforcing the importance of vaccinating early enough to allow antibody transfer.

4 Eligibility for vaccinations

The Green Book is published by UK Health Security Agency and provides information for public health professionals on immunisation, including RSV vaccination (The Green Book | Immunisation againist infectious disease). Considering this advice and that of the Joint Committee on Vaccination and Immunisation (JCVI), the Chief Medical Officer in Northern Ireland issued a letter for the RSV vaccination programme year outlining who is eligible for vaccination. For more information on the vaccination programmes in Northern Ireland, including eligibility for vaccination, please visit NIDirect | Respiratory Syncytial Virus (RSV).

5 Methods

Data is presented to the end of the 2024/25 RSV vaccination programme, 31 August 2025.

Data is provisional and accurate at the time of extraction, 28 January 2026. Data lags exist between date of administration of the vaccine and date of recording on VMS.

6 Supplementary tables

Table 1: RSV vaccination coverage in women who delivered during the programme in Northern Ireland by month of delivery, 2024/25.

Table 2: RSV vaccination coverage in women who delivered during the programme in Northern Ireland by age at delivery, 2024/25.

Table 3: RSV vaccination coverage in women who delivered during the programme in Northern Ireland by Local Government District, 2024/25.