Coronavirus patients in areas that had high levels of air pollution before the pandemic are more likely to die from the infection than patients in cleaner parts of the country, according to a new nationwide study that offers the first clear link between long-term exposure to pollution and Covid-19 death rates.
In an analysis of 3,080 counties in the United States, (https://projects.iq.harvard.edu/covid-pm) researchers at the Harvard University T.H. Chan School of Public Health found that higher levels of the tiny, dangerous particles in air known as PM 2.5 were associated with higher death rates from the disease.
“The results of this paper suggest that long-term exposure to air pollution increases vulnerability to experiencing the most severe Covid-19 outcomes,” the authors wrote. For example, it found that a person living for decades in a county with high levels of fine particulate matter is 15 percent more likely to die from the coronavirus than someone in a region with one unit less of the fine particulate pollution.
The paper has been submitted for peer review and publication in the New England Journal of Medicine.
Over all, the research could have significant implications for how public health officials choose to allocate resources like ventilators and respirators as the coronavirus spreads.
“This study provides evidence that counties that have more polluted air will experience higher risks of death for Covid-19,” said Francesca Dominici, a professor of biostatistics at Harvard who led the study. Counties with higher pollution levels, Dr. Dominici said, “will be the ones that will have higher numbers of hospitalizations, higher numbers of deaths and where many of the resources should be concentrated.”
Dr. John R. Balmes, a spokesman for the American Lung Association and a professor of medicine at University of California, San Francisco, said the findings were particularly important for hospitals in poor neighborhoods and communities of color, which tend to be exposed to higher levels of air pollution than affluent, white communities.
Most fine particulate matter comes from fuel combustion, like automobiles, refineries and power plants, as well as some indoor sources like tobacco smoke. Breathing in such microscopic pollutants, experts said, inflames and damages the lining of the lungs over time, weakening the body’s ability to fend off respiratory infections. Multiple studies have found that exposure to fine particulate matter puts people at heightened risk for lung cancer, heart attacks, strokes and even premature death.