Comparing nose-throat swabs and nasopharyngeal aspirates collected from children with symptoms for respiratory virus identification using real-time polymerase chain reaction.
OBJECTIVE
The objective of this study was to calculate sensitivity values for the detection of major respiratory viruses of childhood by using combined nose-throat swabs and nasopharyngeal aspirates.


METHODS
Children who had symptoms and presented to a pediatric teaching hospital and had a diagnostic respiratory specimen collected were enrolled, and paired nose-throat swab and nasopharyngeal aspirate specimens were collected. Parents were asked to collect the nose-throat swab specimen in the first instance but could defer to a health care worker if unwilling. Nose-throat swab collectors were asked to rate perceived quality of collection. All nasopharyngeal aspirates were collected by a health care worker by using a standard protocol. Real-time polymerase chain reaction for 8 respiratory viruses was performed in our hospital's diagnostic laboratory.


RESULTS
Paired nose-throat swab/nasopharyngeal aspirate specimens were collected during 303 illnesses, with at least 1 respiratory virus identified in 186 (61%). For the major pathogens of childhood, influenza A virus and respiratory syncytial virus, collection by using the nose-throat swab had a sensitivity of 91.9% and 93.1%, respectively. A health care worker collected 219 (72%) of the nose-throat swab specimens; concordance with the nasopharyngeal aspirate was not related to health care worker collection or perceived quality of collection.


CONCLUSIONS
Nose-throat swab specimens, in combination with sensitive molecular testing, are a less invasive diagnostic respiratory specimen with adequate sensitivity for use in the clinic and hospital outpatient settings and large-scale community studies through parent collection. For children who present to a hospital in which an avian or pandemic strain of influenza virus is reasonably part of the differential diagnosis, nasopharyngeal aspirates or a similar collection technique (eg, nasal washes) should continue to be used.
Lambert
Stephen B
SB
MBBS, Queensland Paediatric Infectious Diseases Laboratory, Royal Children's Hospital, Herston Queensland 4029, Australia. sblambert@uq.edu.au
Whiley
David M
DM
O'Neill
Nicholas T
NT
Andrews
Emily C
EC
Canavan
Fiona M
FM
Bletchly
Cheryl
C
Siebert
David J
DJ
Sloots
Theo P
TP
Nissen
Michael D
MD
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000032:analysis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D009980:Influenza A virus / Q000235:genetics*; D007251:Influenza, Human / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D008297:Male; D009305:Nasopharynx / Q000821:virology*; D009666:Nose / Q000821:virology*; D016133:Polymerase Chain Reaction / Q000379:methods; D011793:Queensland / Q000453:epidemiology; D015203:Reproducibility of Results; D018357:Respiratory Syncytial Virus Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D012136:Respiratory Syncytial Viruses / Q000235:genetics*; D012189:Retrospective Studies
D004279:DNA, Viral