Air Filtration to reduce Respiratory Infections (including COVID-19) in care homes: the AFRI-c cluster randomised controlled trial with nested internal pilot, process and economic evaluations

Aim: The overall aim is to investigate the clinical and cost effectiveness of portable HEPA air filters in reducing symptomatic winter respiratory infections (including COVID-19) in residents of older people’s care homes. BACKGROUND To date SARS-CoV-2 infection has led to over one million deaths worldwide, with elderly care home residents disproportionately affected. There are currently 220,000 people over 65 years living in UK care homes, and this number is predicted to double by 2040. Respiratory infections (including SARS-CoV-2) are mainly spread when people breathe in or swallow airborne droplets containing germs. Care homes are obliged to follow DH&SC ‘Code of Practice on the Prevention and Control of Infections’, but airborne transmission remains largely unmitigated. Portable high efficiency particulate (HEPA) air filtration units trap droplet and aerosolised bacteria and viruses, but research is urgently needed to help health and social care providers know whether portable HEPA filters are clinically and cost-effective in reducing symptomatic respiratory infections. OBJECTIVES Primary objective: To investigate the effect of portable HEPA air filters in private residential, communal and staff only rooms on residents’ symptomatic winter respiratory infection episodes (including COVID-19) in care homes with air filters compared with residents in care homes without air filters. Secondary objectives: 1. To determine the effect of air filters installed in private residential, communal and staff only rooms during the winter months versus no air filters on residents’: a. Respiratory infections (symptomatic days) b. Fever and/or delirium and/or acute deterioration in physical ability (episodes and symptomatic days) c. Gastro-intestinal infection (episodes & symptomatic days) d. Antibiotic use (courses prescribed/days consumed) e. Number of falls/near falls f. Possible SARS-CoV-2 and Influenza-like illness infection episodes g. PCR confirmed SARS-CoV-2 infections h. PCR (or other test) confirmed Influenza A&B infections i. Other microbiologically confirmed infections including Streptococcal, Meningococcal, Respiratory Syncytial Virus, Norovirus and Human Metapneumovirus infections j. GP diagnosed respiratory (including COVID), gastrointestinal, skin and urinary infections k. Perception of care home environment 2. To determine the effect of air filters versus no air filters installed during winter months on staff members’: a. Sickness days away from work b. Change over time in staff confidence in, and use of, infection prevention and control strategies. c. PCR confirmed SARS-CoV-2 infections d. PCR (or other test) confirmed Influenza A&B infections e. Other microbiologically confirmed infections including Streptococcal, Meningococcal, Respiratory Syncytial Virus, Norovirus and Human Metapneumovirus infections f. Perception of care home environment 3. To determine the cost-effectiveness of air filter use in reducing symptomatic respiratory infection episodes(to include hospital admissions, deaths and cause of death). 4. To identify the views of care homes, local authority and CCG commissioners on intervention maintenance, sustainability and possible dissemination. 5. In the intervention arm: a. To explore staff, resident and residents’ relatives' attitudes to and perceptions and experiences of air filters and determine factors influencing their use, including acceptability, satisfaction and potential benefits and harms. b. To assess the fidelity of the intervention. DESIGN A two-arm, 1:1 cluster randomisation controlled trial of portable HEPA air filters versus no air filters for reducing symptomatic winter respiratory infections (including COVID-19) in care home residents with mixed method process and economic evaluation. PROJECT TIMETABLE The funding start date for this trial is 01 July 2021 and the study duration is expected to be 42 months, to 31st December 2024. ANTICIPATED IMPACT AND DISSEMINATION Preventing infections could improve resident and staff quality of life, resident quantity of life, and the efficient use of health and social care resources, all expected to increase as the population ages. We will create a dissemination plan our collaborators and PPI, outputs to include: plain English summaries; publications/ presentations in high impact journals/ conferences; online webinars for care home managers, CCG and local authority commissioners.