New Research Links Air Pollution to Higher Coronavirus Death Rates
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WASHINGTON — 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, 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.
在对美国3080个县进行的分析中，哈佛大学陈曾熙公共卫生学院(Harvard T.H. Chan School of Public Health)发现，空气中细小而危险的PM2.5颗粒的高含量水平与该疾病的较高死亡率存在关联。
For weeks, public health officials have surmised a link between dirty air and death or serious illness from Covid-19, which is caused by the coronavirus. The Harvard analysis is the first nationwide study to show a statistical link, revealing a “large overlap” between Covid-19 deaths and other diseases associated with long-term exposure to fine particulate matter.
“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.
The paper found that if Manhattan had lowered its average particulate matter level by just a single unit, or one microgram per cubic meter, over the past 20 years, the borough would most likely have seen 248 fewer Covid-19 deaths by this point in the outbreak.
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. The paper has been submitted for peer review and publication in the New England Journal of Medicine.
总体而言，该研究可能会对公共卫生官员在冠状病毒传播时期对呼吸机等资源的分配问题上产生重大影响。该论文已提交至《新英格兰医学杂志》(New England Journal of Medicine)进行同行评审和发表。
It found that just a slight increase in long-term pollution exposure could have serious coronavirus-related consequences, even accounting for other factors like smoking rates and population density.
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 District of Columbia, for instance, is likely to have a higher death rate than the adjacent Montgomery County, Md. Cook County, Ill., which includes Chicago, should be worse than nearby Lake County, Ill. Fulton County, Ga., which includes Atlanta, is likely to suffer more deaths than the adjacent Douglas County.
“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.”
The study is part of a small but growing body of research, mostly still out of Europe, that offers a view into how a lifetime of breathing dirtier air can make people more susceptible to the coronavirus, which has already killed more than 10,000 people in the United States and 74,000 worldwide.
In the short term, Dr. Dominici and other public health experts said the study’s finding meant that places like the Central Valley of California, or Cuyahoga County, Ohio, may need to prepare for more severe cases of Covid-19.
The analysis did not look at individual patient data and did not answer why some parts of the country have been hit harder than others. It also remains unclear whether particulate matter pollution plays any role in the spread of the coronavirus or whether long-term exposure directly leads to a greater risk of falling ill.
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.
美国肺脏协会(American Lung Association)发言人、加州大学旧金山分校医学教授约翰·R·巴尔姆斯(John R. Balmes)说，这些发现对贫困社区和有色人种社区的医院尤为重要。这些社区往往比富裕的白人社区受到更高水平的空气污染。
“We need to make sure that hospitals taking care of folks who are more vulnerable and with even greater air pollution exposure have the resources they need,” Dr. Balmes said.
As more is learned about the recurrence of Covid-19, the study also could have far-reaching implications for clean-air regulations, which the Trump administration has worked to roll back over the past three years on the grounds that they have been onerous to industry.
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. In 2003, Dr. Zuo-Feng Zhang, the associate dean for research at the University of California, Los Angeles, Fielding School of Public Health, found that SARS patients in the most polluted parts of China were twice as likely to die from the disease as those in places with low air pollution.
In an interview, Dr. Zhang called the Harvard study “very much consistent” with his findings.