id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-268074-9mact9br	Bi, Qifang	Epidemiology and transmission of COVID-19 in 391 cases and 1286 of their close contacts in Shenzhen, China: a retrospective cohort study	2020-04-27		.txt	text/plain	5307	238	51	We compared cases identified through symptomatic surveillance and contact tracing, and estimated the time from symptom onset to confirmation, isolation, and admission to hospital. We characterise differences in demographics and severity between cases identified through symptom-based surveillance and monitoring of close case contacts, and estimate the time to key events, such as confirmation, isolation, and recovery. Using data from contact tracing, we characterise SARS-CoV-2 transmission by estimating key values, such as the household secondary attack rate, serial interval, and observed reproductive number (R). This study is, to our knowledge, the first analysis of SARS-CoV-2 transmission and COVID-19 natural history based on a large primary dataset of cases and close contacts, for which the mode of surveillance (ie, symptom-based versus contact-based) was sufficiently documented and RT-PCR testing was nearly universal. Between Jan 14 and Feb 12, 2020, the Shenzhen CDC confirmed 391 cases of SARS-CoV-2 infection ( of 87) than were those detected through contact-based surveillance (tables 1, 2).	./cache/cord-268074-9mact9br.txt	./txt/cord-268074-9mact9br.txt