Determinants of physical distancing during the covid-19 epidemic in Brazil: effects from mandatory rules, numbers of cases and duration of rules

Abstract During the covid-19 pandemic, physical distancing is being promoted to reduce the disease transmission and pressure on health systems. Yet, what determines physical distancing? Through a panel data analysis, this article identifies some of its determinants. Using a specifically built index that measures the strictness of physical distancing rules in the 27 Brazilian states, this paper isolates the effect of mandatory physical distancing rules from other potential determinants of physical distancing. The article concludes that physical distancing is influenced by at least three variables: the strictness of mandatory physical distancing rules, the number of confirmed cases of covid-19, and the duration of rules. Evidence also indicates that the effect of physical distancing measures is relatively stronger than that of the number of cases –physical distancing is determined proportionally more by mandatory policies than people’s awareness about the severity of the epidemic. These results have at least two policy implications. First, governments should adopt mandatory measures in order to increase physical distancing – rather than expect people to adopt them on their own. Second, the timing of adopting them is important, since people are unlikely to comply with them for long periods of time.

摘要 在新型冠状病毒肺炎（COVID-19）大流行期间，各国普遍推行社交距离（physical distancing）措施以降低病毒传播风险、缓解医疗卫生系统承压状况。然而，究竟哪些因素会影响社交距离的执行效果？本文通过面板数据分析，识别了社交距离执行的若干影响因素。研究构建了一项专门用于衡量巴西27个州社交距离管控严格程度的指数，借此将强制性社交距离规定的效应，与其他潜在影响因素分离开来。本文研究结论显示，社交距离的执行至少受三类变量影响：强制性社交距离规定的严格程度、新冠确诊病例数，以及管控措施的持续时长。研究证据同时表明，社交距离措施本身的效应较确诊病例数的影响更为显著——即社交距离的执行更多由强制性防疫政策所决定，而非民众对疫情严重性的认知。上述研究结论至少包含两项政策启示：其一，政府应通过推行强制性管控措施提升社交距离的执行水平，而非寄望于民众自发践行；其二，管控措施的推行时机至关重要，因为民众难以长期遵守此类防疫规定。