研究称，空气污染高的县Covid-19死亡率上升

研究称，空气污染高的县Covid-19死亡率上升

You are more likely to die from Covid-19 if you live in a county in the United States with higher levels of long-term air pollution, according to new research released Tuesday by Harvard T.H. Chan School of Public Health.

哈佛公共卫生学院周二公布的一项新研究显示，如果你长期生活在美国一个空气污染程度较高的县，你更可能死于Covid-19.

"We found that an increase of only 1 gram per cubic meter in fine particulate matter in the air was associated with a 15% increase in the Covid-19 death rate," said lead author Francesca Dominici, co-director of the Harvard Data Science Initiative.

“我们发现，空气中细颗粒物每立方米仅增加1克，Covid-19 的死亡率就会增加15%，”该研究的主要作者、哈佛数据科学计划的联合主任弗朗西斯卡·多米尼奇说。

The study defined high pollution levels as fine particulate matter (PM 2.5) levels above 13 micrograms per cubic meter of air, much higher than the US mean of 8.4.

该研究将高污染水平定义为每立方米空气中的细颗粒物(PM2.5)含量超过13微克，远高于美国的平均值8.4微克。

"The results suggest that long-term exposure to air pollution increases vulnerability to experiencing the most severe Covid-19 outcomes," Dominici said.

多米尼奇说:“研究结果表明，长期暴露于空气污染中，更容易出现最严重的Covid-19症状。”

The new information should be used by federal, state and local officials to make informed decisions about enforcing social distancing and preparing hospitals and local health care systems for a potential influx of more severe cases that will need extreme measures such as ventilators, Dominici said.

多米尼奇说，联邦、州和地方官员应该利用这些新信息做出明智的决定，加强社会距离，并为医院和地方卫生保健系统做好准备，以应对可能出现的更严重的病例，这些病例需要使用呼吸机等强度措施。

"We know the counties that have higher pollution levels historically," she said. "We know that even if they [the counties] haven't experienced high number of deaths yet, that would be one of their higher risks."

“我们知道历史上污染水平较高的县，”她说我们知道，即使他们(县)的死亡人数还不高，这也是他们面临的更高风险之一。”

Particulate matter is a mixture of solid and liquid matter found in the air. Dust, dirt and smoke particles are larger but there are also extremely small, inhalable particulates that can't be seen with the naked eye. Those are called PM 2.5 because their size is generally 2.5 micrometers or less.

微粒物质是在空气中发现的固体和液体物质的混合物。灰尘、尘土和烟雾颗粒较大，但也有极小的可吸入颗粒物，肉眼无法看到。这些被称为PM2.5.因为它们的大小通常是2.5微米或更小。

That's really tiny -- for comparison, an average human hair is 30 times larger than a PM 2.5 particle. Because they are so small, these particulates can get deep into the lungs and wreak havoc with our lungs and bodily functions.

相比之下，人类头发的平均直径是PM2.5的30倍。因为这些微粒很小，它们可以深入肺部，对我们的肺部和身体机能造成严重破坏。

The researchers then compared those county-level maps of air pollution to current numbers of deaths from Covid-19 through April 4. a number tallied by Johns Hopkins University.

然后，研究人员将这些县级的空气污染地图与目前的covid19死亡人数(截至4月4日)进行了比较。约翰霍普金斯大学统计了这个数字。

There is a large overlap between the underlying conditions that put many Covid-19 patients at risk -- such as lung, kidney and heart conditions -- and diseases made worse by long-term exposure to fine particulate matter.

导致许多Covid-19患者面临肺部、肾脏和心脏疾病风险的潜在疾病与长期暴露于细颗粒物中而病情恶化的疾病之间存在很大重叠。

A prior study of 60 million Americans over age 65 by the same research group found that each 1 gram per cubic meter rise in long-term PM 2.5 exposure was associated with a 0.73% increase in the rate of death from any cause.

该研究小组此前对6.000万65岁以上的美国人进行的一项研究发现，长期接触PM2.5每增加1克，任何原因导致的死亡率都会增加0.73%。

Compared to those results, the new study showed the same small increase led to a "Covid-19 death rate of a magnitude that is 20 times the one estimated for all-cause mortality."

与这些结果相比，新的研究表明，同样的小幅度增长导致了“Covid-19的死亡率，是全因死亡率的20倍。”

The study said those findings held true after a large set of "socioeconomic, demographic, weather, behavioral, and healthcare-related confounders" were taken into account.

该研究称，在考虑了大量“社会经济、人口统计学、天气、行为和医疗相关的混杂因素”后，这些发现仍然成立。

The study has some limitations, the authors said, including the fact that the data was averaged at a county level.

该研究有一些局限性，作者说，包括数据的平均水平是在县一级。

"If they knew at the individual level the deaths from Covid-19. and knew whether the dead person smoked, had hypertension, had diabetes or any of the other known risk factors, that it would be a stronger analysis," said pulmonologist Dr. John Balmes, a professor of medicine at University of California, San Francisco.

加州大学旧金山分校医学教授约翰·巴尔姆斯博士说：“如果他们从个体水平上知道Covid-19的死亡情况，知道死者是否吸烟、高血压、糖尿病或其他已知的危险因素，这将是一个更有力的分析。”