This ecological study investigated the association between COVID-19 distribution and air quality index (AQI), comorbidities and sociodemographic factors in the USA. The AQI factors included in the study are total AQI, ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide (NO2). Other demographic, socioeconomic, and geographic variables were included as covariates. The correlations of COVID-19 variables—proportion of cases and deaths in each population, as well as case fatality rate with independent variables were determined by Pearson and Spearman correlation and multiple linear regression analyses. The results revealed that AQI-NO2, population density, longitude, gross domestic product per capita, median age, total death of disease, and pneumonia per population were significantly associated with the COVID-19 variables (P < 0.05). Air pollutants, especially NO2 in the US case, could be addressed as an important factor linked with COVID-19 susceptibility and mortality.

中文翻译：

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COVID-19 分布与空气质量、社会人口因素和合并症的关联：美国各州的生态研究

这项生态研究调查了美国 COVID-19 分布与空气质量指数 (AQI)、合并症和社会人口因素之间的关联。研究中包括的 AQI 因素是总 AQI、臭氧、一氧化碳、二氧化硫和二氧化氮 (NO2)。其他人口、社会经济和地理变量作为协变量包括在内。COVID-19 变量的相关性——每个人群中病例和死亡的比例，以及病死率与自变量的相关性由 Pearson 和 Spearman 相关性和多元线性回归分析确定。结果显示，AQI-NO2、人口密度、经度、人均国内生产总值、中位年龄、疾病总死亡人数和人均肺炎与 COVID-19 变量显着相关（P < 0.05）。