Streptococcus pneumoniae in Medical Districts of Burkina Faso: Serotype Distribution and Antibiotic Susceptibility during 2010 to 2012

Abstract

Introduction: Streptococcus pneumoniae is a highly virulent pathogen. Despite the recent introduction of vaccines in the program of prevention in Burkina Faso, treatment by antibiotics has remained in use. The aim of this study was to determine the serotypes implied in invasive pneumococcal infections and their resistance to antibiotics used for routine treatment in Burkina Faso. Methods: From March 2010 to December 2012, a total of 6,102 cerebrospinal fluid (CSF) and pleural fluid (PF) specimens were collected in Burkina Faso. The specimens were analyzed by latex agglutination assay, culture, and real time polymerase chain reaction (rt-PCR) for species identification. Serotyping was performed by rt-PCR and minimum inhibitory concentrations were determined by the E-test. Results: Among 562 S. pneumoniae strains identified from 6,102 specimens, 440 isolates were serotyped by rt-PCR. Serotypes 1 and 5 were the most common (50%); however, 70 (15.9%) strains were not detected by rt-PCR methodology. Among patients of less than 20 years of age, serotype 1 was the most frequent strain identified (9.3% to 13.2%). Ampicillin and ceftriaxone were the most active antibiotics in vitro against the strains identified. The rate of S. pneumoniae strains susceptible to chloramphenicol was 83%. Serotypes 1 (7/49) and 5 (5/7) were non-susceptible to chloramphenicol. Conclusion: Serotypes 1 and 5 were the common serotypes identified. Conjugate vaccines introduced in Burkina Faso should take in account these valences, to decrease the incidence of pneumococcal infections efficiently.