Region-specific air pollutants and meteorological parameters influence COVID-19: A study from mainland China

Abstract

Coronavirus disease 2019 (COVID-19) was first detected in December 2019 in Wuhan, China, with 11,669,259 positive cases and 539,906 deaths globally as of July 8, 2020. The objective of the present study was to determine whether meteorological parameters and air quality affect the transmission of COVID-19, analogous to SARS. We captured data from 29 provinces, including numbers of COVID-19 cases, meteorological parameters, air quality and population flow data, between Jan 21, 2020 and Apr 3, 2020. To evaluate the transmissibility of COVID-19, the basic reproductive ratio ( R 0 ) was calculated with the maximum likelihood “removal” method, which is based on chain-binomial model, and the association between COVID-19 and air pollutants or meteorological parameters was estimated by correlation analyses. The mean estimated value of R 0 was 1.79 ± 0.31 in 29 provinces, ranging from 1.08 to 2.45. The correlation between R 0 and the mean relative humidity was positive, with coefficient of 0.370. In provinces with high flow, indicators such as carbon monoxide (CO) and 24-h average concentration of carbon monoxide (CO_24 h) were positively correlated with R 0 , while nitrogen dioxide (NO 2 ), 24-h average concentration of nitrogen dioxide (NO 2 _24 h) and daily maximum temperature were inversely correlated to R 0 , with coefficients of 0.644, 0.661, −0.636, −0.657, −0.645, respectively. In provinces with medium flow, only the weather factors were correlated with R 0 , including mean/maximum/minimum air pressure and mean wind speed, with coefficients of −0.697, −0.697, −0.697 and −0.841, respectively. There was no correlation with R 0 and meteorological parameters or air pollutants in provinces with low flow. Our findings suggest that higher ambient CO concentration is a risk factor for increased transmissibility of the novel coronavirus, while higher temperature and air pressure, and efficient ventilation reduce its transmissibility. The effect of meteorological parameters and air pollutants varies in different regions, and requires that these issues be considered in future modeling disease transmissibility.

Effects of Demographic and Weather Parameters on COVID-19 Basic Reproduction Number

“…While an established correlation between virus transmission and a certain factor is not, in general, a telltale sign of a direct causal relationship between them, in the case of temperature and humidity such connection is firmly indicated also by results of experimental research (Lowen et al, 2007;Casanova et al, 2010;Chan et al, 2011;van Doremalen et al, 2020). Nevertheless, some studies yielded different conclusions, most likely due to the method of calculating R 0 or due to choosing a small/uninformative sample of populations in which the number of infected cases was monitored (Guo et al, 2020;Lin et al, 2020;Yao et al, 2020b). For example, a study focused on the suburbs of New York, Queens, obtained a positive correlation between virus transmission and temperature, which seems unexpected given the prevailing observations of other studies (Adhikari and Yin, 2020).…”

The Effects of Air Pollution on COVID-19 Infection and Mortality—A Review on Recent Evidence

“…This study demonstrated that contaminated air accelerates the transmission of the SARS-CoV-2 to humans other than the transmission from human to human. CO concentration was a risk factor for the increased spreading of SARS-CoV-2, while higher temperature, efficient ventilation and air pressure reduced its transmissibility (26). In another study, after adjusting to temperature and relative humidity, SO 2 , NO 2 , CO, and O 3 , the case fatality rate (CFR) showed a positive association with PM 2.5 and PM 10 in China (27).…”

Initial COVID-19 Transmissibility and Three Gaseous Air Pollutants (NO2, SO2, and CO): A Nationwide Ecological Study in China

“…Population flow from Wuhan City may be another potential confounding factor since it may result in disentangled imported or local cases for other Chinese cities. An emerging study found that correlations between gaseous pollutants and R 0 varied in provinces with different population flow (27). However, the effect is likely uniform across cities, and the lockdown of Wuhan mitigated the COVID-19 exportation to other cities effectively.…”