sharon sanders
Editor-in-Chief & President
Temporal dynamics in viral shedding and transmissibility of COVID-19
Xi He1,3, Eric H. Y. Lau 2,3 ✉, Peng Wu2 , Xilong Deng1 , Jian Wang1 , Xinxin Hao2 , Yiu Chung Lau2 , Jessica Y. Wong2 , Yujuan Guan1 , Xinghua Tan1 , Xiaoneng Mo1 , Yanqing Chen1 , Baolin Liao1 , Weilie Chen1 , Fengyu Hu1 , Qing Zhang1 , Mingqiu Zhong1 , Yanrong Wu1 , Lingzhai Zhao1 , Fuchun Zhang1 , Benjamin J. Cowling 2,4, Fang Li1,4 and Gabriel M. Leung 2,4
We report temporal patterns of viral shedding in 94 patients with laboratory-confirmed COVID-19 and modeled COVID-19 infectiousness profiles from a separate sample of 77 infector–infectee transmission pairs. We observed the highest viral load in throat swabs at the time of symptom onset, and inferred that infectiousness peaked on or before symptom onset. We estimated that 44% (95% confidence interval, 25–69%) of secondary cases were infected during the index cases’ presymptomatic stage, in settings with substantial household clustering, active case finding and quarantine outside the home. Disease control measures should be adjusted to account for probable substantial presymptomatic transmission.
more..
https://www.nature.com/articles/s41591-020-0869-5.pdf
Xi He1,3, Eric H. Y. Lau 2,3 ✉, Peng Wu2 , Xilong Deng1 , Jian Wang1 , Xinxin Hao2 , Yiu Chung Lau2 , Jessica Y. Wong2 , Yujuan Guan1 , Xinghua Tan1 , Xiaoneng Mo1 , Yanqing Chen1 , Baolin Liao1 , Weilie Chen1 , Fengyu Hu1 , Qing Zhang1 , Mingqiu Zhong1 , Yanrong Wu1 , Lingzhai Zhao1 , Fuchun Zhang1 , Benjamin J. Cowling 2,4, Fang Li1,4 and Gabriel M. Leung 2,4
We report temporal patterns of viral shedding in 94 patients with laboratory-confirmed COVID-19 and modeled COVID-19 infectiousness profiles from a separate sample of 77 infector–infectee transmission pairs. We observed the highest viral load in throat swabs at the time of symptom onset, and inferred that infectiousness peaked on or before symptom onset. We estimated that 44% (95% confidence interval, 25–69%) of secondary cases were infected during the index cases’ presymptomatic stage, in settings with substantial household clustering, active case finding and quarantine outside the home. Disease control measures should be adjusted to account for probable substantial presymptomatic transmission.
more..
https://www.nature.com/articles/s41591-020-0869-5.pdf