This note studies the effect of the availability of a test for a virus on the public health of a population. It is shown by example that the existence of a freely available and moderately informative test for a virus may lower society's welfare in comparison to the case where no test exists or access to the test is restricted. In this setting, any test provided to any subset of agents who would find it optimal not to isolate absent the test improves welfare.

中文翻译：

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对病毒的不完美测试可能比根本没有测试更糟糕


本报告研究了病毒检测的可用性对人群公共卫生的影响。例子表明，与不存在检测或检测机会受到限制的情况相比，免费提供且信息量适中的病毒检测的存在可能会降低社会福利。在这种情况下，向任何认为最好不要在没有测试的情况下进行隔离的代理人子集提供的任何测试都会改善福利。