title: Prevalence of Bordetella pertussis and Bordetella parapertussis in infants presenting to the emergency department with bronchiolitis.
abstract: BACKGROUND
  The clinical presentation of Bordetella pertussis can overlap with that of respiratory syncytial virus (RSV), and coinfection does occur, but management differs.
  
  
  OBJECTIVE
  The prevalence of B. pertussis is < 2% among Emergency Department (ED) patients with bronchiolitis. Our secondary hypothesis was that the prevalence of Bordetella parapertussis is also < 2% among these patients.
  
  
  METHODS
  Nasal washings were obtained from children up to 18 months of age (inclusive) who presented to a county hospital ED with a clinical diagnosis of bronchiolitis. These washings were frozen to -70°C before testing for B. pertussis and B. parapertussis using species-specific real-time polymerase chain reaction (PCR) assays. The assays were optimized to target conserved regions within a complement gene and the CarB gene, respectively. A Bordetella spp. genus-specific real-time PCR assay was designed to detect the Bhur gene of B. pertussis, B. parapertussis, and B. bronchiseptica. RSV antigen detection was also performed.
  
  
  RESULTS
  There were 227 patients enrolled. After exclusions, 204 remained in the analysis. RSV antigen testing was positive in 109/186 (59%) of the patients in whom it was performed. All samples were tested for B. pertussis. B. parapertussis testing could not be completed on 23 samples. No cases (0/204; 95% confidence interval [CI] 0-1.8%) tested positive for B. pertussis or B. parapertussis (0/181; 95% CI 0-2%).
  
  
  CONCLUSIONS
  The prevalence of B. pertussis in children presenting to the ED with bronchiolitis was < 2%.
authors.affiliation: Department of Emergency Medicine, Kern Medical Center, Bakersfield, California 93305, USA.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Walsh
authors.forename: Lauren
authors.initials: L
authors.lastname: Kimmel
authors.forename: Melanie
authors.initials: M
authors.lastname: Feola
authors.forename: Ty
authors.initials: T
authors.lastname: Tran
authors.forename: Christina
authors.initials: C
authors.lastname: Lim
authors.forename: Lisa
authors.initials: L
authors.lastname: De Salvia
authors.forename: James
authors.initials: J
authors.lastname: Pusavat
authors.forename: Scott
authors.initials: S
authors.lastname: Michaelson
authors.forename: Tuan Anh
authors.initials: TA
authors.lastname: Nguyen
authors.forename: Kirt
authors.initials: K
authors.lastname: Emery
authors.forename: Eli
authors.initials: E
authors.lastname: Mordechai
authors.forename: Martin E
authors.initials: ME
authors.lastname: Adelson
mesh_terms: D001885:Bordetella Infections / Q000175:diagnosis / Q000453:epidemiology*; D042483:Bordetella parapertussis / Q000302:isolation & purification*; D001886:Bordetella pertussis / Q000302:isolation & purification*; D001988:Bronchiolitis / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D015331:Cohort Studies; D003937:Diagnosis, Differential; D004636:Emergency Service, Hospital; D005260:Female; D006784:Hospitals, Teaching; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D018357:Respiratory Syncytial Virus Infections / Q000175:diagnosis / Q000453:epidemiology*; D018570:Risk Assessment; D012720:Severity of Illness Index; D014917:Whooping Cough / Q000175:diagnosis / Q000453:epidemiology*