title: Evaluation of swabbing methods for estimating the prevalence of bacterial carriage in the upper respiratory tract: a cross sectional study.
abstract: OBJECTIVE
  Bacterial carriage in the upper respiratory tract is usually asymptomatic but can lead to respiratory tract infection (RTI), meningitis and septicaemia. We aimed to provide a baseline measure of Streptococcus pneumoniae, Moraxella catarrhalis, Pseudomonas aeruginosa, Staphylococcus aureus, Haemophilus influenzae and Neisseria meningitidis carriage within the community. Self-swabbing and healthcare professional (HCP) swabbing were compared.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Individuals registered at 20 general practitioner practices within the Wessex Primary Care Research Network South West, UK.
  
  
  METHODS
  10,448 individuals were invited to participate; 5394 within a self-swabbing group and 5054 within a HCP swabbing group. Self-swabbing invitees included 2405 individuals aged 0-4 years and 3349 individuals aged ≥5 years. HCP swabbing invitees included 1908 individuals aged 0-4 years and 3146 individuals aged ≥5 years.
  
  
  RESULTS
  1574 (15.1%) individuals participated, 1260 (23.4%, 95% CI 22.3% to 24.5%) undertaking self-swabbing and 314 (6.2%, 95% CI 5.5% to 6.9%) undertaking HCP-led swabbing. Participation was lower in young children and more deprived practice locations. Swab positivity rates were 34.8% (95% CI 32.2% to 37.4%) for self-taken nose swabs (NS), 19% (95% CI 16.8% to 21.2%) for self-taken whole mouth swabs (WMS), 25.2% (95% CI 20.4% to 30%) for nasopharyngeal swabs (NPS) and 33.4% (95% CI 28.2% to 38.6%) for HCP-taken WMS. Carriage rates of S. aureus were highest in NS (21.3%). S. pneumoniae carriage was highest in NS (11%) and NPS (7.4%). M. catarrhalis carriage was highest in HCP-taken WMS (28.8%). H. influenzae and P. aeruginosa carriage were similar between swab types. N. meningitidis was not detected in any swab. Age and recent RTI affected carriage of S. pneumoniae and H. influenzae. Participant costs were lower for self-swabbing (£41.21) versus HCP swabbing (£69.66).
  
  
  CONCLUSIONS
  Higher participation and lower costs of self-swabbing as well as sensitivity of self-swabbing favour this method for use in large population-based respiratory carriage studies.
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: A L
authors.initials: AL
authors.lastname: Coughtrie
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: R N
authors.initials: RN
authors.lastname: Whittaker
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: N
authors.initials: N
authors.lastname: Begum
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: R
authors.initials: R
authors.lastname: Anderson
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: A
authors.initials: A
authors.lastname: Tuck
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.|Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton Foundation NHS Trust, Southampton, UK.|Southampton NIHR Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton, UK.
authors.forename: S N
authors.initials: SN
authors.lastname: Faust
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.|Southampton NIHR Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton, UK.
authors.forename: J M
authors.initials: JM
authors.lastname: Jefferies
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: H M
authors.initials: HM
authors.lastname: Yuen
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: P J
authors.initials: PJ
authors.lastname: Roderick
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.|NIHR Research Design Service South Central, University Hospital Southampton Foundation NHS Trust, Southampton, UK.
authors.forename: M A
authors.initials: MA
authors.lastname: Mullee
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: M V
authors.initials: MV
authors.lastname: Moore
authors.affiliation: Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.|Southampton NIHR Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton, UK.|Public Health England, Southampton, UK.
authors.forename: S C
authors.initials: SC
authors.lastname: Clarke
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000175:diagnosis / Q000453:epidemiology*; D002353:Carrier State / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006193:Haemophilus influenzae / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D001936:Moraxella catarrhalis / Q000302:isolation & purification; D009055:Mouth / Q000382:microbiology*; D009296:Nasal Cavity / Q000382:microbiology*; D009305:Nasopharynx / Q000382:microbiology*; D009345:Neisseria meningitidis / Q000302:isolation & purification; D010865:Pilot Projects; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D012648:Self Care; D013048:Specimen Handling / Q000379:methods*; D013211:Staphylococcus aureus / Q000302:isolation & purification; D013296:Streptococcus pneumoniae / Q000302:isolation & purification; D006113:United Kingdom; D055815:Young Adult
keywords: Epidemiology < INFECTIOUS DISEASES; MICROBIOLOGY; PRIMARY CARE; Respiratory infections < THORACIC MEDICINE