waterok 发表于 2020-4-20 11:58

哈佛大学:PM2.5污染严重的地区 新冠肺炎死亡率明显更高

哈佛大学学者的一项研究发现,新冠肺炎死亡率的急剧上升与空气污染有关。空气中被称为PM2.5的微小颗粒会导致长期的健康问题,它们是由工业、汽车和化石燃料燃烧产生的。研究人员发现,即使PM2.5浓度小幅升高,感染冠状病毒后死亡的几率也会显著增加。“我们发现PM2.5(粒子)只增加1μg/m3, Covid-19死亡率增加了15%。”团队用他们的令人震惊的研究发现。科学家们汇总了美国约3000个县(占全国人口的98%)的空气污染数据,并与新冠病毒的数据进行了比较。他们调整了可能影响调查结果的因素,如贫困水平、吸烟、肥胖、检查次数和医院床位数量。分析显示,长期暴露在PM2.5中会显著增加新冠肺炎的死亡几率。空气污染会削弱人体的呼吸道,并抑制其预防感染的能力,而众所周知,感染会带来各种原因导致更高的死亡率。然而,这种相关性在SARS-CoV-2病毒引起的COVID-19疾病中是20倍。在这项研究中,哈佛数据科学的联合负责人Francesca Dominici写到:“我们假设因为长期接触PM2.5,对呼吸道和心血管系统造成不利影响,它还可以加重COVID-19感染症状的严重程度和COVID-19患者可能会增加死亡的风险。”“在美国和世界范围内,PM2.5与健康,包括妊娠结果、呼吸系统疾病、心血管疾病、神经认知疾病之间的关系已经得到了很好的证实。”污染抑制了人体抵御病原体进入肺部的第一道防线,被称为纤毛的细小毛发变得不那么有效。这些细小的毛发不能捕捉和清除感染,因此这些人更容易患上慢性呼吸道疾病。COVID-19以呼吸道为目标,可导致呼吸短促、肺活量下降,最终死亡。目前尚无有效的疫苗或治疗方法。该研究只收集了美国的数据,但其影响广泛,世界各地的空气污染都超过了安全限度。研究人员将高污染定义为PM2.5水平高于每立方米空气13微克,高于美国平均水平8.4微克。然而,世界卫生组织(WHO)推荐的是10 μg/m3。研究人员说,空气污染严重的地方应该利用这些发现,确保严格遵守社交距离准则,因为这些地区的居民最容易出现严重症状。研究人员得出结论说,研究结果强调了在COVID-19危机期间和之后继续执行现有空气污染法规以保护人类健康的重要性。研究人员公开了他们的发现、模型和代码,以供其他科学家扩展研究。由于迫切需要更多关于冠状病毒大流行的信息,这项研究尚未经过同行评议,但据信将很快在一份权威医学杂志上发表。目前可以在medRxiv预印本网站上找到。随着旅行和排放量的下降,世界各地的空气污染正在减缓。例如,medRxiv最近发表的一项研究显示,中国的封锁和抗冠状病毒措施使一些城市的空气污染减少了四分之一。科学家们说,如果这种低水平持续下去,一个月可以挽救3.6万人的生命。2月初,由于冠状病毒肆虐城市,数百万人被困家中,大部分地区都进入了隔离状态。分析在几十个中国城市在封锁后,空气中PM2.5水平下降了22.3μg每立方米。该研究的作者称,污染的减少“可能会带来巨大的健康益处”。原文来源:https://www.dailymail.co.uk/scie ... -air-pollution.html
https://www.nytimes.com/2020/04/07/climate/air-pollution-coronavirus-covid.html

waterok 发表于 2020-4-20 12:35

New Research Links Air Pollution to Higher Coronavirus Death Rates

Atlanta on Saturday evening. The area is likely to suffer more deaths than the adjacent Douglas County, Ga.Kevin C. Cox/Getty Images
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.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.
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.

“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.


A temporary hospital under construction Friday at McCormick Place, a convention center in Chicago.Pool photo by Chris Sweda

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.“The study results underscore the importance of continuing to enforce existing air pollution regulations to protect human health both during and after the Covid-19 crisis,” the study said.Last week, the Trump administration announced a plan to weaken Obama-era regulations on automobile tailpipe emissions, asserting the rollback would save lives because Americans would buy newer, safer vehicles. But the administration’s own analysis also found that there would be even more premature deaths from increased air pollution.In weakening a regulation last year on carbon pollution from coal-fired power plants, the Environmental Protection Agency similarly acknowledged that the measure was likely to result in about 1,400 additional premature deaths a year because of more pollution.Asked whether the E.P.A. was also studying the link between air pollution and the virus or considering policies to address the link, Andrea Woods, a spokeswoman for the agency, referred the question to the Centers for Disease Control and Prevention, and asserted that the Trump administration rollbacks would lead to some air quality improvements.







页: [1]
查看完整版本: 哈佛大学:PM2.5污染严重的地区 新冠肺炎死亡率明显更高