### Summary box #### What are the new findings? #### How might it impact on healthcare in the future? The transmission dynamics of SARS-CoV-2 are complex. They depend on factors that enhance or protect against fomite, large droplet and aerosol transmission, as well as local prevalence of disease. The public face challenges in understanding and making educated decisions about daily activities, prompting perspective pieces such as ‘We’ve been left to calculate our virus risk on our own. We’re terrible at it.’1 Mobile apps could play an important role in helping individuals understand infection risk from everyday activities. Current COVID-19 risk apps range from predictive models estimating the risk of critical illness, to symptom checkers and workplace guides. Here we present the development and implementation of MyCOVIDRisk app, intended to both inform Americans of the risk incurred when engaging in different activities and to guide on risk-reduction measures. Our objective was to create a tool that was freely accessible to the public, incorporated up-to-date information on local disease prevalence2 and helped people easily understand how to reduce risk without divulging personal information. The hypothesis was that if individuals could continue to engage in enjoyable low-risk activities, we could reduce community transmission while also minimising anxiety, isolation and so-called pandemic fatigue. ### Literature review The idea of MyCOVIDRisk was conceived in July 2020 …

中文翻译：

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MyCOVIDRisk 应用程序：开发和利用 COVID-19 风险评估和缓解应用程序

### 摘要框#### 有哪些新发现？#### 它对未来的医疗保健有何影响？SARS-CoV-2 的传播动力学很复杂。它们取决于增强或防止污染物、大飞沫和气溶胶传播以及当地疾病流行的因素。公众在理解日常活动并做出明智的决定方面面临着挑战，这引发了诸如“我们只能自己计算病毒风险”等观点文章。我们在这方面做得很糟糕。'1 移动应用程序可以在帮助个人了解日常活动中的感染风险方面发挥重要作用。当前的 COVID-19 风险应用程序范围从估计危重疾病风险的预测模型到症状检查器和工作场所指南。在这里，我们介绍了 MyCOVIDRisk 应用程序的开发和实施，旨在告知美国人在从事不同活动时所面临的风险，并指导降低风险的措施。我们的目标是创建一个可供公众免费使用的工具，纳入有关当地疾病流行情况的最新信息2，并帮助人们轻松了解如何在不泄露个人信息的情况下降低风险。假设是，如果个人能够继续从事愉快的低风险活动，我们就可以减少社区传播，同时最大限度地减少焦虑、孤立和所谓的大流行疲劳。### 文献综述 MyCOVIDRisk 的想法是在 2020 年 7 月构思的……