Epidemiology and Infection

Original Papers

Other Bacterial infections

High prevalence of nasal carriage of β-lactamase-negative ampicillin-resistant Haemophilus influenzae in healthy children in Korea

S. M. BAEa1, J. H. LEEa1, S. K. LEEa1, J. Y. YUa1, S. H. LEEa2 and Y. H. KANGa1 c1

a1 Division of Bacterial Respiratory Infections, Center for Infectious Diseases, National Institute of Health, Korea Centers for Disease Control and Prevention, Chungcheongbuk-do, Korea

a2 NeoDin Medical Institute, Seoul, Korea

SUMMARY

This study investigated the carriage of antimicrobial resistant Haemophilus influenzae in 582 healthy children attending kindergarten or elementary school at four intervals over a 9-month period in Seoul, Korea. Diverse colonization patterns and a lower level of long-term persistent carriage by H. influenzae status were evident in this study. Colonizing H. influenzae isolates showed a high rate of resistance to β-lactams including ampicillin (51·9%), cefaclor (52·1%), and amoxicillin/clavulanate (16·3%). Based on the ampicillin resistance mechanism, H. influenzae isolates were categorized as β-lactamase-negative, ampicillin-susceptible (BLNAS) (48·1%), β-lactamase-positive, ampicillin-resistant (BLPAR) (22·6%), β-lactamase-negative, ampicillin-resistant (BLNAR) (22·8%), and β-lactamase-positive, amoxicillin/clavulanate-resistant (BLPACR) strains (6·5%). This study provides the first evidence of a high prevalence (22·8%) of BLNAR strains of H. influenzae nasal carriage in healthy children attending kindergarten or the first 2 years of elementary school in Korea. The high carriage of these resistant strains in overcrowded urban settings may create reservoirs for development of H. influenzae-resistant strains.

(Received February 07 2012)

(Revised May 08 2012)

(Accepted May 08 2012)

(Online publication May 30 2012)

Key words

  • BLNAR strains;
  • Haemophilus influenzae ;
  • nasal carriage

Correspondence:

c1 Author for correspondence: Y. H. Kang, Director, Division of Bacterial Respiratory Infections, Center for Infectious Diseases, National Institute of Health, Korea Centers for Disease Control and Prevention, Osong Health Technology Administration Complex, 643, Yeonje-ri, Gangoe-myeon, Cheongwon-gun, Chungcheongbuk-do, 363-951, Korea. (Email: slowpc@hanmail.net)

Metrics