Haemophilus influenzae: Characterization of the isolates recovered from invasive diseases in Cuba from 2008-2011 [Haemophilus influenzae: Caracterización de aislamientos recuperados de enfermedades invasivas en Cuba durante el período 2008-2011]
Torano G.,Instituto Pedro Kouri LNRH IPK |
Menendez D.,Instituto Pedro Kouri LNRH IPK |
Llop A.,Instituto Pedro Kouri LNRH IPK |
Dickinson F.,Instituto Pedro Kouri LNRH IPK |
And 3 more authors.
VacciMonitor | Year: 2012
In order to characterize Haemophilus influenzae isolates responsible for invasive disease (ID) in Cuba during the post-vaccination period, we studied the total isolates recovered from 2008 to 2011 and submitted to the Institute «Pedro Kouri» from different provinces. Specie confirmation and serotype determination were performed by considering the factors V and X requirements and using the agglutination plate method, respectively. Biotypes were defined by testing indol, urea and ornithine. The minimum inhibitory concentration (MIC) was assessed by ellipsometer test for ampicillin, ceftriaxone, chloramphenicol and rifampicin. Twenty three isolates were identified as H. influenzae; of them, 21 were serotyped and two non-typable (HNT). Near ninety percent of the serotyped isolates were classified as serotype b and only 2 as serotype a. Nine isolates of H. influenzae b belonged to biotype I while serotype a and HNT isolates corresponded to biotype II. In one strain it was demonstrated production of ß -lactamase enzyme as well as resistance to ampicillin (MIC=8 μg/mL) and chloramphenicol (MIC=12 μg/mL). It was evident that despite the decline in the incidence of Hib ID, this serotype is still the most common in Cuba, and highlights the need for ongoing monitoring to detect vaccine failures. The antimicrobial susceptibility observed during this period might be considered as an additional benefit of vaccination.