Table 2

Association between annual mean levels of air pollutants and COVID-19 incidence rate, and estimated number of additional COVID-19 cases due to air pollution, in single-pollutant models

Air pollutantModel 1Model 2
RR95% CIRR95% CICases*95% CI
PM2.51.0511.027 to 1.0761.0511.027 to 1.075294.1152.7 to 435.5
PM101.0401.021 to 1.0601.0401.020 to 1.060230.9115.6 to 346.1
NO21.0201.009 to 1.0301.0201.009 to 1.030113.151.7 to 174.5
NO1.0411.014 to 1.0681.0401.013 to 1.068235.570.6 to 400.4
O30.9800.970 to 0.9900.9800.970 to 0.990−115.0−174.0 to −57.0
  • Rate ratios (RRs) per 1 µg/m3 increase in the annual average exposure to each pollutant estimated from Poisson regression models.

  • Model 1: single pollutants, adjusting for age, sex and living in a residential care home.

  • Model 2: Model 1 + positive history of stroke, treatment for diabetes, antihypertensive treatment and treatment for obstructive airway diseases.

  • *Number of cases per 100 000 person-years due to 1 µg/m3 increase in the pollutant above its mean value, estimated at the mean values of the confounders.