ABSTRACT
OBJECTIVE: To analyze the profile of antimicrobial susceptibility of meningococcal disease isolates collected throughout Brazil from 2006 to 2008 and forwarded to the National Reference Laboratory for Meningitis, Institute Adolfo Lutz - São Paulo. MATERIALS AND METHODS: The MIC to penicillin, ampicillin, chloramphenicol, ceftriaxone, ciprofloxacin and rifampicin was determined in a sample of 1096 (55% of the total isolates received) randomly chosen using the broth microdilution procedure. The breakpoints used were those recommended by the European Monitoring Group on Meningococci (EMGM). RESULTS: Decreased susceptibility to penicillin and ampicillin was detected in 13% and 12.9% respectively. All isolates were susceptible to chloramphenicol, ceftriaxone, and ciprofloxacin. Two strains (0.2%) showed high resistance to rifampicin and 0.5% of the isolates displayed intermediate resistance to rifampicin. CONCLUSIONS: The meningococcal strains isolated in Brazil during 2006-2008 were globally susceptible to all antibiotics currently used in treatment or chemoprophylaxis of meningococcal disease in Brazil.
Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial , Meningitis, Meningococcal/microbiology , Neisseria meningitidis/drug effects , Adolescent , Adult , Anti-Bacterial Agents/therapeutic use , Brazil/epidemiology , Child , Child, Preschool , Chloramphenicol/pharmacology , Ciprofloxacin/pharmacology , Female , Humans , Infant , Male , Meningitis, Meningococcal/drug therapy , Meningitis, Meningococcal/epidemiology , Meningitis, Meningococcal/prevention & control , Microbial Sensitivity Tests , Neisseria meningitidis/isolation & purification , Rifampin/pharmacology , Serotyping , Species Specificity , Young Adult , beta-Lactams/pharmacologyABSTRACT
Meningococcal disease is characterized by cyclic fluctuations in incidence, serogroup distribution, and antigenic profiles. In greater São Paulo, Brazil, there has been a constant increase in the incidence of serogroup C meningococcal disease since the late 1980s. To gain an understanding of changes in serogroup C meningococcal disease over three decades in greater São Paulo, Brazil, 1,059 invasive Neisseria meningitidis serogroup C isolates from 1976 and 2005 were analyzed. Three major clone complexes, sequence type (ST)-11, ST-8, and ST-103, were identified by multilocus sequence typing, and the isolates were characterized by serotyping and 16S rRNA typing. During the 30-year period, there were two major antigenic replacements: from 2a:P1.(5,2) to 2b:P1.3 and subsequently to 23:P1.14-6. All strains of clone ST-103 were characterized as serotype 23 and serosubtype P1.14-6. The origin of 23:P1.14-6 ST-103 complex strains is unknown, but efforts are needed to monitor its spread and define its virulence. The antigenic replacements we observed likely represent a mechanism to sustain meningococcal disease in the population as immunity to circulating strains accumulated.
