Applied Health Research Centre (Jüni, Rothenbühler, Bobos, Thorpe, da Costa, Slutsky) Li Ka Shing Knowledge Institute of St. Michael's Hospital; Department of Medicine and Institute of Health Policy, Management and Evaluation (Jüni), University of Toronto, Toronto, Ont.; Ava AG (Rothenbühler), Zürich, Switzerland; Department of Health and Rehabilitation Sciences (Bobos), Western University, London, Ont.; Dalla Lana School of Public Health (Thorpe, Fisman, Gesink), University of Toronto, Toronto, Ont.; Institute of Primary Health Care (da Costa), University of Bern, Switzerland; Interdepartmental Division of Critical Care Medicine (Slutsky), University of Toronto, Toronto, Ont.
CMAJ. 2020 May 25;192(21):E566-E573. doi: 10.1503/cmaj.200920. Epub 2020 May 8.
It is unclear whether seasonal changes, school closures or other public health interventions will result in a slowdown of the current coronavirus disease 2019 (COVID-19) pandemic. We aimed to determine whether epidemic growth is globally associated with climate or public health interventions intended to reduce transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
We performed a prospective cohort study of all 144 geopolitical areas worldwide (375 609 cases) with at least 10 COVID-19 cases and local transmission by Mar. 20, 2020, excluding China, South Korea, Iran and Italy. Using weighted random-effects regression, we determined the association between epidemic growth (expressed as ratios of rate ratios [RRR] comparing cumulative counts of COVID-19 cases on Mar. 27, 2020, with cumulative counts on Mar. 20, 2020) and latitude, temperature, humidity, school closures, restrictions of mass gatherings, and measures of social distancing during an exposure period 14 days previously (Mar. 7 to 13, 2020).
In univariate analyses, there were no associations of epidemic growth with latitude and temperature, but weak negative associations with relative humidity (RRR per 10% 0.91, 95% confidence interval [CI] 0.85-0.96) and absolute humidity (RRR per 5 g/m 0.92, 95% CI 0.85-0.99). Strong associations were found for restrictions of mass gatherings (RRR 0.65, 95% CI 0.53-0.79), school closures (RRR 0.63, 95% CI 0.52-0.78) and measures of social distancing (RRR 0.62, 95% CI 0.45-0.85). In a multivariable model, there was a strong association with the number of implemented public health interventions ( for trend = 0.001), whereas the association with absolute humidity was no longer significant.
Epidemic growth of COVID-19 was not associated with latitude and temperature, but may be associated weakly with relative or absolute humidity. Conversely, public health interventions were strongly associated with reduced epidemic growth.
目前尚不清楚季节性变化、学校停课或其他公共卫生干预措施是否会导致当前 2019 年冠状病毒病（COVID-19）大流行的放缓。我们旨在确定全球传染病的流行是否与旨在降低严重急性呼吸系统综合征冠状病毒 2（SARS-CoV-2）传播的气候或公共卫生干预措施有关。
我们对全球所有 144 个地缘政治区域（375609 例）进行了前瞻性队列研究，这些区域至少有 10 例 COVID-19 病例和当地传播，不包括中国、韩国、伊朗和意大利。使用加权随机效应回归，我们确定了传染病流行（用 2020 年 3 月 27 日与 2020 年 3 月 20 日相比的 COVID-19 病例累计计数的比率比值 [RRR] 表示）与纬度、温度、湿度、学校停课、集会限制以及在 14 天前（2020 年 3 月 7 日至 13 日）的暴露期内的社会疏远措施之间的关联。
在单变量分析中，传染病的流行与纬度和温度无关，但与相对湿度呈弱负相关（每增加 10%，RRR 为 0.91，95%置信区间 [CI] 为 0.85-0.96）和绝对湿度（每增加 5g/m，RRR 为 0.92，95%CI 为 0.85-0.99）。大型集会限制（RRR 为 0.65，95%CI 为 0.53-0.79）、学校停课（RRR 为 0.63，95%CI 为 0.52-0.78）和社会隔离措施（RRR 为 0.62，95%CI 为 0.45-0.85）与限制有很强的关联。在多变量模型中，与实施的公共卫生干预措施数量之间存在很强的关联（ for 趋势=0.001），而与绝对湿度的关联不再显著。
COVID-19 的流行与纬度和温度无关，但可能与相对湿度或绝对湿度有关。相反，公共卫生干预措施与传染病的流行呈负相关。
