title: Concurrent detection of other respiratory viruses in children shedding viable human respiratory syncytial virus.
abstract: Human respiratory syncytial virus (HRSV) is an important cause of respiratory disease. The majority of studies addressing the importance of virus co-infections to the HRSV-disease have been based on the detection of HRSV by RT-PCR, which may not distinguish current replication from prolonged shedding of remnant RNA from previous HRSV infections. To assess whether co-detections of other common respiratory viruses are associated with increased severity of HRSV illnesses from patients who were shedding viable-HRSV, nasopharyngeal aspirates from children younger than 5 years who sought medical care for respiratory infections in Ribeirão Preto (Brazil) were tested for HRSV by immunofluorescence, RT-PCR and virus isolation in cell culture. All samples with viable-HRSV were tested further by PCR for other respiratory viruses. HRSV-disease severity was assessed by a clinical score scale. A total of 266 samples from 247 children were collected and 111 (42%) were HRSV-positive. HRSV was isolated from 70 (63%), and 52 (74%) of them were positive for at least one additional virus. HRSV-positive diseases were more severe than HRSV-negative ones, but there was no difference in disease severity between patients with viable-HRSV and those HRSV-positives by RT-PCR. Co-detection of other viruses did not correlate with increased disease severity. HRSV isolation in cell culture does not seem to be superior to RT-PCR to distinguish infections associated with HRSV replication in studies of clinical impact of HRSV. A high rate of co-detection of other respiratory viruses was found in samples with viable-HRSV, but this was not associated with more severe HRSV infection.
authors.affiliation: Department of Cell and, Molecular Biology, University of Sao Paulo School of Medicine, Ribeirão Preto, SP, Brazil.
authors.forename: T B
authors.initials: TB
authors.lastname: Gagliardi
authors.forename: F E
authors.initials: FE
authors.lastname: Paula
authors.forename: M A
authors.initials: MA
authors.lastname: Iwamoto
authors.forename: J L
authors.initials: JL
authors.lastname: Proença-Modena
authors.forename: A E
authors.initials: AE
authors.lastname: Santos
authors.forename: A A
authors.initials: AA
authors.lastname: Camara
authors.forename: M C
authors.initials: MC
authors.lastname: Cervi
authors.forename: O A L
authors.initials: OA
authors.lastname: Cintra
authors.forename: E
authors.initials: E
authors.lastname: Arruda
mesh_terms: D001938:Brazil; D002675:Child, Preschool; D060085:Coinfection / Q000473:pathology / Q000821:virology*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009305:Nasopharynx / Q000821:virology; D012328:RNA Viruses / Q000302:isolation & purification*; D012141:Respiratory Tract Infections / Q000473:pathology / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012720:Severity of Illness Index; D014776:Virus Cultivation; D014777:Virus Diseases / Q000473:pathology / Q000821:virology*
keywords: HRSV infection; HRSV isolation; respiratory virus co-infection; severity of HRSV disease