title: Use of an improved quantitative polymerase chain reaction assay to determine differences in human rhinovirus viral loads in different populations.
abstract: Human rhinoviruses (HRV) frequently cause acute respiratory infections and chronic respiratory disease exacerbations. However, testing is not generally offered. We developed a modified HRV quantitative polymerase chain reaction (qPCR) assay to assess viral loads in the community and hospital patients. The assay had a lower limit of detection of 2 log(10) viral copies/mL and displayed linearity over 5 log(10) viral copies, with a lower limit of quantitation of 4 log(10) viral copies/mL. Mean viral loads (95% confidence interval) for hospitalized children, university students, and institutionalized elderly, were 7.08 log(10) viral copies/mL (6.7-7.5), 6.87 log(10) viral copies/mL (6.5-7.2), and 7.09 log(10) viral copies/mL (6.9-7.3), respectively (P = 0.67). Serial specimens of 14 university students showed a decrease of mean viral loads from 6.36 log(10) viral copies/mL on day 1 to 2.32 log(10) viral copies/mL 7 days past symptom onset (P < 0.001). Using an HRV qPCR, we showed that viral loads did not differ between the community and hospitalized populations and significantly decreased following symptoms onset in healthy individuals.
authors.affiliation: St. Joseph's Healthcare, Hamilton, ON, Canada.
authors.forename: Andrea
authors.initials: A
authors.lastname: Granados
authors.forename: Kathy
authors.initials: K
authors.lastname: Luinstra
authors.forename: Sylvia
authors.initials: S
authors.lastname: Chong
authors.forename: Emma
authors.initials: E
authors.lastname: Goodall
authors.forename: Lisa
authors.initials: L
authors.lastname: Banh
authors.forename: Samira
authors.initials: S
authors.lastname: Mubareka
authors.forename: Marek
authors.initials: M
authors.lastname: Smieja
authors.forename: James
authors.initials: J
authors.lastname: Mahony
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010850:Picornaviridae Infections / Q000821:virology*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D012229:Rhinovirus / Q000302:isolation & purification*; D019562:Viral Load / Q000379:methods*; D055815:Young Adult