A relationship between infecting dose and risk of disease severity has not been demonstrated for COVID-19.
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We report three clusters of COVID-19 in Madrid, in which infected persons experienced different disease severity according to distinct sizes of viral inoculum.
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Smaller viral inoculi as a result of wide social distancing would contribute to the lower pathogenicity of recent SARS-CoV-2 infections.
Abstract
A relationship between the infecting dose and the risk of disease severity has not been demonstrated for SARS-CoV-2 infection. Here, we report three clusters of individuals that were potentially exposed to distinct inoculum in Madrid. Overall each group developed divergent clinical forms of COVID-19. Our data support that a greater viral inoculum at the time of SARS-CoV-2 exposure might determine a higher risk of severe COVID-19.