Table 7. Hospitalisation data for the 700 care home residents with genomic data available 700/1167 (60.0%) care home residents identified in the study had genomic data available and were used to define care home SARS-CoV-2 clusters.

We investigated the proportions of these care home residents that were hospitalised and may have acquired their infections through interactions with hospitals. This was possible for 694/700 (99.1%) individuals who had NHS numbers documented that could be linked with national hospitalisation data. Being hospitalised due to COVOD-19 was defined as the date of first positive sampling being within 2 days prior to admission up to 7 days post-admission. Suspected hospital-acquired COVID-19 infections were defined as first positive test being 7 days or more after hospital admission date and prior to discharge date (N = 13) or within 7 days following hospital discharge (N = 27). Of the latter group, 10 individuals were admitted to hospital and discharged on the same day prior to their positive test, nine were admitted for 1–7 days, and eight had been admitted for greater than 7 days.

Category	Counts (%)
Care home residents with genomic data	700
Care home residents with genomic data that could be linked to hospitalisation data	694/700 (99.1%)
Hospitalised during study period	470/694 (67.7%)
Hospitalised due to COVID-19	398/694 (57.3%)
Suspected hospital-acquired COVID-19	40/694 (5.76%)
Discharged within 7 days of positive test	230/694 (33.1%)