title: High levels of multiple antibiotic resistance among 938 Haemophilus influenzae type b meningitis isolates from Cuba (1990-2002).
abstract: OBJECTIVE
  A national surveillance study to determine antimicrobial susceptibility in Haemophilus influenzae type b isolated from cerebrospinal fluid was carried out in Cuba from 1990 to 2002.
  
  
  METHODS
  Susceptibility to ampicillin, co-amoxiclav, cefotaxime, ceftriaxone, co-trimoxazole, tetracycline, chloramphenicol and rifampicin was tested by the microdilution method according to the NCCLS guidelines.
  
  
  RESULTS
  The 34 participating laboratories recovered 938 consecutive, non-identical isolates. All the isolates were retrieved from children aged <5 years. The mean number of isolates collected by year in the pre-vaccination era (1990-1998) was 93; after vaccination, 57 isolates were reported in 1999, 31 in 2000, four in 2001 and five in 2002. Resistance to ampicillin, co-trimoxazole, tetracycline and chloramphenicol was 46.3% (all beta-lactamase-positive), 51.3%, 33.2% and 44.0%, respectively. Ampicillin-resistant beta-lactamase-negative strains were not detected. All strains were susceptible to co-amoxiclav, cefotaxime, ceftriaxone and rifampicin. Ampicillin resistance was strongly associated with resistance to tetracycline, co-trimoxazole and chloramphenicol (P<0.001). Multidrug resistance was present in 43.8% of isolates. The most prevalent phenotype was resistance to ampicillin/chloramphenicol/tetracycline/co-trimoxazole, which was detected in 29.2% of strains overall. An increase in the prevalence of resistance to these antibiotics was observed from 1990 to 2000 in the range 40.7%-54.8% for ampicillin, 40.1%-51.6% for chloramphenicol, 45.4%-58.1% for co-trimoxazole and 23%-45.2% for tetracycline.
  
  
  CONCLUSIONS
  In Cuba, the widespread vaccination against Haemophilus influenzae type b prevented a large number of meningitis cases in children caused by strains resistant to multiple antibiotics.
authors.affiliation: Laboratorio Nacional de Referencia de Haemophilus, Instituto de Medicina Tropical, La Habana, Cuba.
authors.forename: Isis
authors.initials: I
authors.lastname: Tamargo
authors.forename: Kiomy
authors.initials: K
authors.lastname: Fuentes
authors.forename: Alina
authors.initials: A
authors.lastname: Llop
authors.forename: Jesús
authors.initials: J
authors.lastname: Oteo
authors.forename: José
authors.initials: J
authors.lastname: Campos
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D002675:Child, Preschool; D016001:Confidence Intervals; D003462:Cuba / Q000453:epidemiology; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects* / Q000502:physiology; D019741:Haemophilus influenzae type b / Q000187:drug effects* / Q000254:growth & development; D006801:Humans; D008583:Meningitis, Haemophilus / Q000188:drug therapy* / Q000453:epidemiology; D008826:Microbial Sensitivity Tests / Q000379:methods / Q000639:trends; D016017:Odds Ratio
chemical_list: D000900:Anti-Bacterial Agents