Occurrence of 3 Bordetella species during an outbreak of cough illness in Ohio: epidemiology, clinical features, laboratory findings and antimicrobial susceptibility.
BACKGROUND
An increase in laboratory diagnosis of pertussis was noted in central Ohio during 2010. Diagnosis was made using a polymerase chain reaction assay targeting the multicopy insertion sequence IS481, which is found in both Bordetella pertussis (Bp) and Bordetella holmesii (Bh). An increase in specimens testing positive for Bordetella parapertussis (Bpp) using insertion sequence IS1001 was also noted.


METHODS
Nasopharyngeal swab specimens submitted April 1, 2010, to March 31, 2011, were tested using a multiplex polymerase chain reaction assay for Bp/Bh (IS481) and Bpp followed by singleplex assays for Bp and Bh. A subgroup of specimens was also cultured for Bordetella species, and antimicrobial susceptibility testing was performed on recovered organisms. Demographic and clinical features were compared for patients with Bp, Bh and Bpp.


RESULTS
Of 520 IS481-positive specimens, 214 (41.1%) were positive for Bp, 79 (15.2%) were positive for Bh and 5 (1.0%) were positive for both Bp and Bh; 222 (42.7%) were negative for both targets. An additional 220 specimens were positive for Bpp. Among a sample of 155 IS481-positive specimens, 40, 15 and 0 were culture positive for Bp, Bh and Bpp, respectively. Among a sample of 55 BparaIS1001-positive (Bpp) specimens, 22, 0 and 0 were culture positive for Bpp, Bp and Bh, respectively. All Bordetella species were susceptible to macrolide antibiotics. Patients with Bh were older than patients with Bp, who were older than those positive for Bpp (mean ages: 12.0, 8.0 and 4.2 years, respectively; P < 0.001). One or more classic signs of pertussis (ie, paroxysmal cough, whoop, post-tussive emesis) were seen in 55.9% of 263 patients (59 Bp, 24 Bh, 80 Bpp and 100 negative for Bordetella species), but did not differ statistically among the groups (χ = 5.1, P = 0.17).


CONCLUSIONS
All 3 Bordetella species, Bp, Bh and Bpp, were detected during on outbreak of pertussis-like cough illness. There were noted differences in age and seasonality, but clinical features at the time of presentation did not allow clear differentiation of these infections. All Bordetella species recovered from culture and tested were susceptible in vitro to macrolide antibiotics. Additional study is necessary to further characterize epidemiologic and clinical characteristics of Bh-associated cough illness and to determine potential co-occurrence of Bordetella species with other bacterial and viral respiratory tract pathogens.
From the *Section of Infectious Diseases, Nationwide Children's Hospital; †College of Medicine, The Ohio State University; ‡Department of Laboratory Medicine, Nationwide Children's Hospital, Columbus, OH; and §Epidemic Intelligence Service, assigned to the Ohio Department of Health, Centers for Disease Control and Prevention, Atlanta, GA.
Kevin B
KB
Spicer
Doug
D
Salamon
Carol
C
Cummins
Amy
A
Leber
Loren E
LE
Rodgers
Mario J
MJ
Marcon
D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001884:Bordetella / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification*; D001885:Bordetella Infections / Q000453:epidemiology* / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D003371:Cough / Q000453:epidemiology* / Q000382:microbiology; D004251:DNA Transposable Elements; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007223:Infant; D018942:Macrolides / Q000494:pharmacology; D008297:Male; D008826:Microbial Sensitivity Tests; D060885:Multiplex Polymerase Chain Reaction; D009305:Nasopharynx / Q000382:microbiology; D009820:Ohio / Q000453:epidemiology; D055815:Young Adult
D000900:Anti-Bacterial Agents; D004251:DNA Transposable Elements; D018942:Macrolides