1. Feasibility of conducting a larger scale trial assessed using data on the recruitment of care homes; recruitment of residents; assessment of background infection rate; assessment of background dietary nitrate intake; adherence to the intervention; ability to measure the ordinal outcome; an estimation of the intra-cluster correlation (ICC); and incidence of death between baseline and 60 days 2. Severity of the first infection measured using a 5 level ordinal outcome (using the worst level if >1 event; where a score of: 0 represents no symptoms of infection; 1 represents symptoms of infection; 2 represents symptoms of infection needing healthcare advice such as a call to 111; or GP appointment; 3 represents hospitalisation for any reason; or intention to hospitalise but advance directive precluded this; or 4 represents death from any cause) between baseline and 60 days

1. Feasibility of conducting a larger scale trial assessed using data on the recruitment of care homes; recruitment of residents; assessment of background infection rate; assessment of background dietary nitrate intake; adherence to the intervention; ability to measure the ordinal outcome; an estimation of the intra-cluster correlation (ICC); and incidence of death between baseline and 60 days 2. Severity of the first infection measured using a 5 level ordinal outcome (using the worst level if >1 event; where a score of: 0 represents no symptoms of infection; 1 represents symptoms of infection; 2 represents symptoms of infection needing healthcare advice such as a call to 111; or GP appointment; 3 represents hospitalisation for any reason; or intention to hospitalise but advance directive precluded this; or 4 represents death from any cause) between baseline and 60 days