Short-term Air Pollution increases risk of positivity of COVID-19 infection: JAMA

A new study published in the Journal of American Medical Association shows that short-term exposure to particulate matter and Black Carbon (BC) was linked to a higher chance of positive SARS-CoV-2 PCR test findings, demonstrating the wide public health advantages of lowering ambient air pollution levels.

Although there is mounting ecological evidence of a link between short-term air pollution exposure and COVID-19, no study has looked at this link on an individual level. As a result, Zhebin Yu and colleagues undertook this research in order to determine the link between short-term exposure to polluted air and SARS-CoV-2 infection in Swedish young people.

From May 5, 2020, through March 31, 2021, this time-stratified case-crossover investigation connected the prospective BAMSE birth cohort to the Swedish national infectious disease registry to identify patients with positive SARS-CoV-2 PCR testing findings. The PCR test date was used as the case day, whereas control days were chosen from weeks having the same day of the week within the same calendar month and year. From September 1 to December 31, 2021, data was analyzed. Dispersion models with high spatiotemporal resolution were used to estimate daily air pollutant levels at residential locations. The key outcome was confirmed SARS-CoV-2 infection among BAMSE cohort members.

The main findings of this study were as follow:

1. A total of 425 cases were found, with 229 (53.9%) of them being women and a median age of 25.6 years.

2. On case days, the median exposure level for PM2.5 was 4.4 g/m3; for PM10, it was 7.7 g/m3; and for NOx, it was 8.2 g/m3 for PM2.5, 6.6 g/m3 for BC, and 7.7 g/m3 for NOx.

3. Each IQR increment in short-term PM2.5 exposure on lag 2 was related with a 6.8% proportionate increase in positive SARS-CoV-2 PCR testing findings; exposure to PM10 on lag 2, 6.9%; and exposure to BC on lag 1, 5.8%.

4. These findings were unaffected by sex, smoking, asthma, being overweight, or self-reported COVID-19 respiratory symptoms, nor were they influenced by sex, smoking, or having asthma.

In conclusion, the results of this case-crossover research of Swedish young adults with air pollution exposure and SARS-CoV-2 infection reveal that residential short-term air pollution exposure is linked to a higher likelihood of SARS-CoV-2 infection PCR test results. These findings back up the idea that lowering ambient air pollution levels has a wide range of health advantages.

Reference:

Yu Z, Bellander T, Bergström A, et al. Association of Short-term Air Pollution Exposure With SARS-CoV-2 Infection Among Young Adults in Sweden. JAMA Netw Open. 2022;5(4):e228109. doi:10.1001/jamanetworkopen.2022.8109