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abstractpubmed· Abstract 2020· item PMID:32453686
Secondary Transmission of Coronavirus Disease from Presymptomatic Persons, China. We explored the secondary attack rate in different types of contact with persons presymptomatic for coronavirus disease (COVID-19). Close contacts who lived with or had frequent contact with an index case-patient had a higher risk for COVID-19. Our findings provide population-based evidence for transmission from persons with presymptomatic COVID-19 infections.