Longitudinal European surveillance study of antibiotic resistance of Haemophilus influenzae

J Antimicrob Chemother. 2006 Oct;58(4):873-7. doi: 10.1093/jac/dkl310. Epub 2006 Aug 4.


Objectives: We assessed the current resistance rates of Haemophilus influenzae against beta-lactams and other agents in Europe and compared the results with those of our previously performed surveillance study.

Methods: MICs of the antibiotics were determined using broth microdilution. The penicillin-binding domain of PBP3 of beta-lactamase (BL)-negative, amoxicillin-resistant (BLNAR) isolates was sequenced.

Results: The percentage of BL-positive and BLNAR strains ranged from 0% to 17.6% and 0% to 33.9%, respectively. Compared with 1997/98 and 2002/03, the overall percentage of strains non-susceptible to amoxicillin decreased from 19.8% and 23.3%, respectively, to 16.4% in 2004/05. The percentage of BL-producing strains decreased from 11.0% and 13.7%, respectively, to 7.6%, whereas the number of BLNAR strains remained stable (8.8% and 9.6%, respectively, versus 8.8% in 2004/05). Comparison of penicillin binding protein (PBP) 3B gene sequences between BLNAR and susceptible strains revealed novel amino acid mutations.

Conclusions: In spite of large inter-regional differences, the overall resistance of H. influenzae to amoxicillin in Europe seems to decline due to a decreasing number of BL-producing strains, whereas the overall percentage of BLNAR strains seems relatively constant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amoxicillin / pharmacology*
  • Anti-Bacterial Agents / pharmacology*
  • Europe
  • Haemophilus influenzae / drug effects*
  • Haemophilus influenzae / genetics
  • Haemophilus influenzae / isolation & purification
  • Humans
  • Microbial Sensitivity Tests
  • Penicillin-Binding Proteins / genetics*
  • Penicillin-Binding Proteins / metabolism
  • Polymerase Chain Reaction
  • Population Surveillance
  • Sequence Analysis, DNA
  • beta-Lactam Resistance*
  • beta-Lactamases / metabolism
  • beta-Lactams / pharmacology


  • Anti-Bacterial Agents
  • Penicillin-Binding Proteins
  • beta-Lactams
  • Amoxicillin
  • beta-Lactamases