Post-graduate Program in Collective Health, University of Vale do Rio dos Sinos, UNISINOS, São Leopoldo, RS, Brazil.
TechnoUp, Jaraguá do Sul, SC, Brazil.
J Infect Dev Ctries. 2022 May 30;16(5):759-767. doi: 10.3855/jidc.15324.
Climate conditions may influence the transmission of COVID-19. Thus, the aim of this study was to evaluate the impact of temperature and relative humidity on COVID-19 cases and related deaths during the initial phase of the epidemic in Brazil.
An ecological study based on secondary data was conducted. Daily data on new COVID-19 cases, deaths, and climate indicators were collected from February 20 to April 18, 2020 (n = 59 days) for all state capital cities in Brazil and the Federal District (Brasília). The climate indicators included mean temperature, temperature amplitude, mean relative humidity, relative humidity amplitude, and percentage of days with mean relative humidity ≤ 65 %. Correlation and multiple linear regression analyses were performed for all cities and stratified by quintiles of the COVID-19 incidence rate.
The mean daily temperature was positively correlated with the number of days until the first COVID-19 case was reported. A lower mean relative humidity was correlated with a lower number of cases and deaths in Brazil, especially when the relative humidity was ≤ 65 %. Higher temperatures and humidity amplitudes were correlated with lower COVID-19 mortality. Additionally, after controlling for humidity, cumulative cases of COVID-19 were inversely associated with temperature in cities with mean temperatures less than 25.8 °C.
Variations in temperature and humidity across the Brazilian territory may have influenced the spread of the novel coronavirus during the initial phase of the epidemic.
气候条件可能会影响 COVID-19 的传播。因此，本研究旨在评估温度和相对湿度对巴西疫情初期 COVID-19 病例和相关死亡的影响。
本研究基于二手数据进行了一项生态学研究。从 2020 年 2 月 20 日至 4 月 18 日（共 59 天），收集了巴西所有州首府和联邦区（巴西利亚）的每日新增 COVID-19 病例、死亡人数和气候指标数据。气候指标包括平均温度、温度幅度、平均相对湿度、相对湿度幅度以及平均相对湿度≤65%的天数百分比。对所有城市以及按 COVID-19 发病率五分位数进行分层，进行了相关性和多元线性回归分析。
平均日温与首例 COVID-19 病例报告之间的天数呈正相关。相对湿度较低与巴西的病例和死亡人数较少相关，尤其是当相对湿度≤65%时。较高的温度和湿度幅度与 COVID-19 死亡率降低相关。此外，在控制湿度后，平均温度低于 25.8°C 的城市中，COVID-19 的累积病例与温度呈负相关。
巴西各地温度和湿度的变化可能会影响新型冠状病毒在疫情初期的传播。
