Impact of weather, air pollution and virus variant on COVID-19 with acute respiratory failure in the emergency department

Background

Air pollution and meteorological factors are thought to contribute to increased risk of severe COVID-19, but the evidence is still controversial. This study aimed to assess the effects of weather, air pollution and SARS-CoV-2 variants on COVID-19 with acute respiratory failure (ARF) and investigate the respiratory management in the emergency department (ED).

Methods

We conducted a prospective observational study of 469 COVID-19 ED visits from March 1, 2020 to December 31, 2023. Data on air pollutant levels and weather variables was obtained from Taiwan Central Weather Bureau (CWB) and Environmental Protection Administration (EPA). The generalized linear models extending bivariate and multivariable Poisson regression models were used to estimate the association between the weather variables, air pollutants, virus variants, and COVID-19 patients with ARF.

Results

Among the 469 patients, 64 % were male, and the mean age was 70 ± 6 years. Overall, 18 % (n = 84) of the cohort died, 43 % (n = 200) were intubated, and 70 % (n = 326) were admitted to the ICU. We observed significantly positive associations between PM_2.5, PM₁₀, temperature, and wind speed with ED visits for COVID-19 with ARF. Every 1 μg/m³ increase in PM_2.5, PM₁₀, each 1 m/s increase in wind speed, and 1 °C increase in temperature were significantly associated with a 34.1 % (95 % CI: 8.2 %–66.1 %), 45.4 % (95 % CI: 39.4 %–46.6 %), 19.0 % (95 % CI: 11.4 %–27.0 %), and 10.4 % (95 % CI: 6.9 %–13.9 %) increase in the average daily number of COVID-19 patients respectively. In contrast, NO₂, SO₂, relative humidity, and sunshine were significantly associated with lower average daily numbers of severe COVID-19 patients. Moreover, virus variants were significantly positive associations between humidity and sunshine, 53.9 % (95 % CI: 37.0 %–70.3 %) and 5.4 % (95 % CI: 0.6 %–10.4 %) respectively.

Conclusion

The relationship between air pollution, climate change, virus variants, and COVID-19 is highly intricate. Air pollution exacerbates the severity of COVID-19, climate change influences virus transmission and human immune responses, and viral variants make pandemic control more challenging. These interactions are critical for future prediction, prevention and responses to global health crises.