Leeson Peter T, Rouanet Louis
Department of Economics George Mason University Fairfax Virginia USA.
South Econ J. 2021 Apr;87(4):1107-1118. doi: 10.1002/soej.12497. Epub 2021 Feb 24.
Negative infectious disease externalities are less prevalent in the absence of government intervention and less costly to society than is often supposed. That is so for three reasons. (1) Unlike externality-creating behaviors in many classical externality contexts, such behaviors are often self-limiting in the context of infectious disease. (2) In market economies, behaviors that may create infectious disease externalities typically occur at sites that are owned privately and visited voluntarily. Owners have powerful incentives to regulate such behaviors at their sites, and visitors face residual infection risk contractually. (3) The social cost of infectious disease externalities is limited by the cheapest method of avoiding externalized infection risk. That cost is modest compared to the one usually imagined: the value of life (or health) lost to the disease if government does not intervene. We elaborate these arguments in the context of the COVID-19 pandemic.
在没有政府干预的情况下，负面传染病外部性的情况比通常认为的更为少见，且对社会造成的成本也更低。原因有三点。（1）与许多经典外部性情境中产生外部性的行为不同，传染病情境下的此类行为往往具有自我限制的特性。（2）在市场经济中，可能产生传染病外部性的行为通常发生在私人所有且人们自愿前往的场所。场所所有者有强大的动机在其场所规范此类行为，而访客通过合同承担剩余感染风险。（3）传染病外部性的社会成本受避免外部感染风险的最便宜方法限制。与通常设想的成本相比，即如果政府不干预，因疾病导致的生命（或健康）损失，这一成本较为适度。我们将在新冠疫情的背景下详细阐述这些观点。
