Question to the Department of Health and Social Care:

To ask His Majesty's Government, further to the Written Answer by Baroness Merron on 29 January (HL13801), whether they plan to collect data on respiratory syncytial virus related hospital admissions of infants under one year old in weekly surveillance reports; if not, for what reason this data is being omitted.

Numbers of respiratory syncytial virus (RSV) admissions in infants are reported by a sentinel network of approximately 15 to 20 National Health Service trusts in England to the Severe Acute Respiratory Infections-Watch Surveillance at the UK Health Security Agency. Participation in this surveillance is completely voluntary for NHS trusts. Therefore, the number of participating trusts can vary from week to week, and comparisons based on simple counts may be misleading.

To provide appropriate context for reported weekly data, weekly admission rates are calculated to monitor trends over time. This uses trust catchment populations published by the Office for Health Improvement and Disparities, which are estimated for under five-year-olds, but which have not been estimated specifically for the under one year old age group, or infants.

Therefore, published rates are based on the available denominator data for the under five-year-olds, and these are publicly available in the national surveillance weekly reports and corresponding datafile at the GOV.UK website.

Further surveillance data and a programme impact assessment will be included in the annual surveillance report on RSV, due to be published in summer 2026. Please refer to the 2024/25 annual surveillance report for a summary of the previous winter season, which is available at the GOV.UK website.

Surveillance reports use hospital admission data and the Office for National Statistics’ mid-year estimates to model catchment populations for hospital trusts. Modelled catchment populations use hospital data, aggregated over three years and resident populations in five-year age bands.