Secondary Transmission of Coronavirus Disease from Presymptomatic Persons, China.Emerg Infect Dis. 2020 Aug; 26(8):1924-1926.EI
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.