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Fluoroquinolone and other antimicrobial resistance in invasive pneumococci, Hong Kong, 1995-2001

Pak-Leung Ho1, Tak-Lun Que, Susan S Chiu

  • 1Department of Microbiology, Queen Mary Hospital, The University of Hong Kong, Hong Kong Special Administrative Region, China. plho@hkucc.hku.hk

Emerging Infectious Diseases
|August 25, 2004
PubMed

Insights

Invasive pneumococci in Hong Kong showed rising levofloxacin resistance, particularly among penicillin-resistant strains. Most penicillin-nonsusceptible strains were covered by pneumococcal vaccines.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Public Health

Background:

  • Invasive pneumococcal disease remains a significant public health concern.
  • Antimicrobial resistance in Streptococcus pneumoniae is a growing challenge worldwide.
  • Understanding local resistance patterns is crucial for effective treatment and prevention strategies.

Purpose of the Study:

  • To determine the antimicrobial susceptibilities of invasive pneumococcal isolates in Hong Kong.
  • To investigate the serotypes of penicillin-nonsusceptible pneumococci and their relation to available vaccines.
  • To assess the prevalence and characteristics of levofloxacin resistance.

Main Methods:

  • Antimicrobial susceptibility testing of 265 invasive Streptococcus pneumoniae isolates against 11 agents.
  • Serotyping of isolates to determine vaccine coverage.
  • Analysis of resistance patterns, particularly for penicillin and levofloxacin.

Main Results:

  • Overall penicillin susceptibility was 62.6%, with 17.4% resistant.
  • Levofloxacin resistance was 3.8% overall, rising to 15.2% in penicillin-resistant isolates.
  • Levofloxacin-resistant isolates were clonally related, found in adults over 50, and showed reduced susceptibility to other antibiotics.
  • 90% of penicillin-nonsusceptible isolates in children under 5 belonged to serotypes covered by the 7-valent pneumococcal conjugate vaccine.

Conclusions:

  • A significant proportion of invasive pneumococci in Hong Kong were resistant or intermediately resistant to penicillin.
  • Emerging levofloxacin resistance, particularly in penicillin-resistant strains, warrants close monitoring.
  • Pneumococcal conjugate and polysaccharide vaccines cover a high percentage of penicillin-nonsusceptible serotypes, highlighting their importance in prevention.

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