Air Pollution Makes Severe COVID Worse

By Reuters Staff

July 13, 2021

NEW YORK (Reuters Health) - Breathing dirty air contributes to COVID-19 severity, according to a study from Detroit, one of America's most polluted cities.

"The key takeaway is that living in a more polluted neighborhood is an independent risk factor for severity of COVID-19 disease," Dr. Anita Shallal of Detroit's Henry Ford Hospital said in a statement from the virtual European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) where she presented the findings.

Given that low-income and minority populations often live in inner cities that may be high-polluted, the study also "calls attention to the systemic inequalities that may have led to the stark differences in COVID-19 outcomes along racial and ethnic lines. Communities of color are more likely to be located in areas closer to industrial pollution, and to work in businesses that expose them to air pollution," Dr. Shallal said.

According to the American Lung Association, Detroit is the 12th most polluted city in the United States, measured by year-round fine particle pollution.

The study team assessed the impact of air pollution on the severity of COVID-19 in 2,038 adults with a positive SARS-CoV-2 test admitted to one of four large hospitals within the Henry Ford health System.

They had data on where the patients lived as well as data from the Environmental Protection Agency and other sources on ambient air pollution (PM2.5), ozone and lead paint.

They found that COVID-19 patients requiring admission to the intensive-care unit ICU and mechanical ventilation were significantly more likely to live in neighborhoods with higher levels of PM2.5 and lead paint.

On multivariate analysis, each increase of 1 ug/m3 in long-term PM2.5 exposure was associated with a 3.5-fold increase (P<0.005) in the odds of ICU admission and a 2.5-fold increase (P<0.005) in the odds of needing mechanical ventilation.

Patients who were male, black, obese and had more severe long-term health problems were much more likely to need mechanical ventilation and to be admitted to the ICU.

"Although it is not clear how air pollutants contribute to more severe disease, it's possible that long-term exposure to air pollution may impair the immune system, leading both to increased susceptibility to viruses and to more severe viral infections," Dr. Shallal said in the statement.

"In a double hit, fine particles in air pollution may also act as a carrier for the virus, increasing its spread," she added.

"Urgent further research is needed to guide policy and environmental protection, to minimize the impact of COVID-19 in highly industrialized communities that are home to our most vulnerable residents," Dr. Shallal said.

SOURCE: European Congress of Clinical Microbiology and Infectious Diseases, online July 9-12, 2021.