Contact patterns play a key role in the spread of respiratory infectious diseases in human populations. During the COVID-19 pandemic the regular contact patterns of the population has been disrupted due to social distancing both imposed by the authorities and individual choices. Here we present the results of a contact survey conducted in Chinese provinces outside Hubei in March 2020, right after lockdowns were lifted. We then leveraged the estimated mixing patterns to calibrate a model of SARS-CoV-2 transmission, which was used to estimate different metrics of COVID-19 burden by age. Study participants reported 2.3 contacts per day (IQR: 1.0-3.0) and the mean per-contact duration was 7.0 hours (IQR: 1.0-10.0). No significant differences were observed between provinces, the number of recorded contacts did not show a clear-cut trend by age, and most of the recorded contacts occurred with family members (about 78%). Our findings suggest that, despite the lockdown was no longer in place at the time of the survey, people were still heavily limiting their contacts as compared to the pre-pandemic situation. Moreover, the obtained modeling results highlight the importance of considering age-contact patterns to estimate COVID-19 burden.
翻译:在COVID-19大流行期间,由于当局和个人选择造成的社会偏差,居民的经常接触模式受到干扰。这里我们介绍2020年3月在湖北以外中国各省进行的接触调查的结果,在解除封锁后立即进行;然后我们利用估计混合模式来校准SARS-COV-2传播模式,该模式用于按年龄估计COVID-19负担的不同度量;研究参与者报告说,每天接触2.3个(IQR:1.0-3.0),平均接触时间为7.0小时(IQR:1.0-10.0)。此外,没有观察到各省之间出现重大差异,记录接触的数量没有显示按年龄分列的明确趋势,记录接触大多发生在家庭成员身上(约78%)。我们的调查结果显示,尽管在调查时,封闭时间已不复存在,但人们的接触仍然严重限制其接触时间,而平均接触时间为7.0小时(IQR:1.0-10/10)。此外,所获得的模型结果突出表明,考虑年龄与COVI估计模式的重要性。