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. 2020 Aug:97:290-292.
doi: 10.1016/j.ijid.2020.06.035. Epub 2020 Jun 14.

Inoculum at the time of SARS-CoV-2 exposure and risk of disease severity

María Pilar Guallar  1 , Rosa Meiriño  2 , Carolina Donat-Vargas  3 , Octavio Corral  4 , Nicolás Jouvé  4 , Vicente Soriano  5
Affiliations

Inoculum at the time of SARS-CoV-2 exposure and risk of disease severity

María Pilar Guallar et al. Int J Infect Dis. 2020 Aug.

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.

Keywords: COVID-19; coronavirus; disease severity; epidemiology; inoculum; outbreak; transmission.

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Figures

Fig. 1
Fig. 1
The timeframe of SARS-CoV-2 infections and COVID-19 disease severity in persons belonging to groups with different viral exposure.
Fig. 2
Fig. 2
Major determinants of SARS-CoV-2 susceptibility to infection and risk for disease severity.
Fig. 3
Fig. 3
Herd immunity needed to halt the COVID-19 pandemic as a function of the average community transmission rate (R0).
See this image and copyright information in PMC

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