title: Duration of RT-PCR positivity in severe acute respiratory syndrome.
abstract: Severe acute respiratory syndrome (SARS) is a highly infectious respiratory infection with a high mortality. The duration of infectivity is unknown. The RT-PCR positivity for SARS-associated coronavirus (SARS-CoV) was followed in 45 virologically confirmed SARS patients. Serial RT-PCRs for SARS-CoV were performed in the nasopharyngeal aspirate, stool and urine of 45 SARS patients who survived until discharge. All patients had at least one site that was positive for SARS-CoV on presentation. Time to RT-PCR conversion was studied in all patients. There were 15 males (33.3%) and 30 females (66.7%), with a mean+/- SD age of 40.7+/-14.7 yrs. The median (range) time of RT-PCR conversion was 30 days (2-81). On discharge from the hospital, 18 (40%) remained RT-PCR positive in at least one site. For patients with positive RT-PCR on discharge, the median (range) time to RT-PCR conversion after discharge was 13 days (2-60). A significant proportion of severe acute respiratory syndrome patients remained RT-PCR positive for severe acute respiratory syndrome-associated coronavirus for a substantial duration after discharge. The clinical significance is unknown and this finding merits further study. It is prudent to advise patients to adhere to strict personal hygiene on discharge until RT-PCR becomes negative.
authors.affiliation: Division of Respiratory Medicine, Dept of Medicine and Geriatrics, United Christian Hospital, Hong Kong SAR, China. chucm@ha.org.hk
authors.forename: C M
authors.initials: CM
authors.lastname: Chu
authors.forename: W S
authors.initials: WS
authors.lastname: Leung
authors.forename: V C C
authors.initials: VC
authors.lastname: Cheng
authors.forename: K H
authors.initials: KH
authors.lastname: Chan
authors.forename: A W N
authors.initials: AW
authors.lastname: Lin
authors.forename: V L
authors.initials: VL
authors.lastname: Chan
authors.forename: J Y M
authors.initials: JY
authors.lastname: Lam
authors.forename: K S
authors.initials: KS
authors.lastname: Chan
authors.forename: K Y
authors.initials: KY
authors.lastname: Yuen
mesh_terms: D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D016001:Confidence Intervals; D004279:DNA, Viral / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011336:Probability; D011379:Prognosis; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018570:Risk Assessment; D045473:Severe acute respiratory syndrome-related coronavirus / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D045169:Severe Acute Respiratory Syndrome / Q000175:diagnosis* / Q000821:virology; D012720:Severity of Illness Index; D013997:Time Factors; D019562:Viral Load
chemical_list: D004279:DNA, Viral