IN JUNE, as the coronavirus swept across the United States, Paloma Beamer spent hours each day helping her university plan for a September reopening. Beamer, an associate professor of public health at the University of Arizona, was helping to test a mobile app that would notify users if they crossed paths with confirmed COVID-19 patients. • A number of such “contact tracing” apps have recently had their trials by fire, and many of the developers readily admit that the technology has not yet proven that it can slow the spread of the virus. But that caveat has not stopped national governments and local communities from using the apps. • “Right now, in Arizona, we're in the full-blown pandemic phase,” Beamer said, speaking in June, well before the new-case count had peaked. “And even manual contact tracing is very limited here—we need whatever tool we can get right now to curb our epidemic.” • Traditionally, tracers would ask newly diagnosed patients to list the people they'd spent time with recently, then ask those people to provide contacts of their own. Such legwork has helped to control other infectious-disease outbreaks, such as syphilis in the United States and Ebola in West Africa. However, while these methods can extinguish the first spark or the last embers of an epidemic, they're no good in the wildfire stage, when the caseload expands exponentially.

中文翻译：

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联系人追踪应用程序的困境：这项关键技术能否既有效又私密？

6 月，随着冠状病毒席卷美国，帕洛玛·比默 (Paloma Beamer) 每天花数小时帮助她的大学计划 9 月重新开放。亚利桑那大学公共卫生学副教授 Beamer 正在帮助测试一款移动应用程序，该应用程序会在用户遇到确诊的 COVID-19 患者时通知用户。• 一些这样的“接触者追踪”应用程序最近在火上进行了试验，许多开发人员欣然承认，该技术尚未证明它可以减缓病毒的传播。但这一警告并没有阻止国家政府和当地社区使用这些应用程序。• “目前，在亚利桑那州，我们正处于大流行阶段，”比默在 6 月份发表讲话时说，远在新病例数达到顶峰之前。“即使是手动接触者追踪在这里也非常有限——我们需要任何我们现在可以得到的工具来遏制我们的流行病。” • 传统上，追踪者会要求新诊断的患者列出他们最近接触过的人，然后要求这些人提供他们自己的联系方式。这种跑腿工作有助于控制其他传染病的爆发，例如美国的梅毒和西非的埃博拉。然而，虽然这些方法可以扑灭流行病的第一个火花或最后的余烬，但它们在野火阶段却无济于事，因为当案件数量呈指数增长时。这种跑腿工作有助于控制其他传染病的爆发，例如美国的梅毒和西非的埃博拉。然而，虽然这些方法可以扑灭流行病的第一个火花或最后的余烬，但它们在野火阶段却无济于事，因为当案件数量呈指数增长时。这种跑腿工作有助于控制其他传染病的爆发，例如美国的梅毒和西非的埃博拉。然而，虽然这些方法可以扑灭流行病的第一个火花或最后的余烬，但它们在野火阶段却无济于事，因为当案件数量呈指数增长时。