title: Viral shedding patterns of coronavirus in patients with probable severe acute respiratory syndrome.
abstract: Severe acute respiratory syndrome (SARS) is thought to be caused by a novel coronavirus, SARS-associated coronavirus. We studied viral shedding of SARS coronavirus to improve diagnosis and infection control. Reverse-transcriptase PCR was done on 2134 specimens of different types. 355 (45%) specimens of nasopharyngeal aspirates and 150 (28%) of faeces were positive for SARS coronavirus RNA. Positive rates peaked at 6-11 days after onset of illness for nasopharyngeal aspirates (87 of 149 [58%], to 37 of 62 [60%]), and 9-14 days for faeces (15 of 22 [68%], to 26 of 37 [70%]). Overall, peak viral loads were reached at 12-14 days of illness when patients were probably in hospital care, which would explain why hospital workers were prone to infection. Low rate of viral shedding in the first few days of illness meant that early isolation measures would probably be effective.
authors.affiliation: Government Virus Unit, Public Health Laboratory Centre, 382 Nam Cheong Street, Shek Kip Mei, Kowloon, Hong Kong, People's Republic of China.
authors.forename: Peter K C
authors.initials: PK
authors.lastname: Cheng
authors.forename: Derek A
authors.initials: DA
authors.lastname: Wong
authors.forename: Louis K L
authors.initials: LK
authors.lastname: Tong
authors.forename: Sin-Ming
authors.initials: SM
authors.lastname: Ip
authors.forename: Angus C T
authors.initials: AC
authors.lastname: Lo
authors.forename: Chi-Shan
authors.initials: CS
authors.lastname: Lau
authors.forename: Eugene Y H
authors.initials: EY
authors.lastname: Yeung
authors.forename: Wilina W L
authors.initials: WW
authors.lastname: Lim
mesh_terms: D000328:Adult; D000368:Aged; D017934:Coronavirus / Q000302:isolation & purification*; D005243:Feces / Q000821:virology; D005260:Female; D006801:Humans; D017758:Infectious Disease Transmission, Patient-to-Professional; D008297:Male; D008875:Middle Aged; D009305:Nasopharynx / Q000821:virology; D012367:RNA, Viral / Q000032:analysis; D012137:Respiratory System / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D045169:Severe Acute Respiratory Syndrome / Q000175:diagnosis / Q000635:transmission / Q000821:virology*; D019562:Viral Load; D017201:Virus Shedding
chemical_list: D012367:RNA, Viral