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Archives of Pathology & Laboratory Medicine

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COVID-19 (Disease) -- United States -- Health care


More than 6 million confirmed cases of COVID-19 (coronavirus disease 2019) have been identified worldwide and a number of case reports1-5 have indicated that COVID-19 has the potential to be transmitted prior to disease onset. Studies have also shown that infectious virus can be isolated from presymptomatic COVID-19 cases6 and although it is unknown what level of infectious virus is needed to confer efficient transmission potential, detection of infectious virus in the upper respiratory tract indicates that presymptomatic transmission of COVID-19 is plausible. Fear of asymptomatic and presymptomatic transmission of COVID-19 has led to considerable concern among public health policy makers, frontline healthcare workers and the public in general. In response, many city, state, and federal leaders have asked for increased testing via reverse transcriptase-polymerase chain reaction (RT-PCR) and serological assays in order to identify asymptomatic cases and potential spreaders. Individual case studies are important for bringing attention to this topic but they do not provide information regarding the overall proportion of transmission events that occur before or after symptom onset. A better understanding of COVID-19 transmission is needed to control this pandemic and although some recent studies have provided new insight, others have fueled increased concerns.


"Note: Due to the extremely time sensitive nature of the content of this article, it has not been copyedited or formatted per journal style. Changes or corrections may be made to this article when it appears in a future print issue of the Archives"



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