Paola Andrea Palacios
Instituto Nacional de Salud, Colombia
Title: Molecular characterization of non-vaccine serotypes 11A, 15 B/C and 23A of Streptococcus pneumoniae recovered from invasive diseases in Colombia
Biography
Biography: Paola Andrea Palacios
Abstract
Introduction. A total of 192 invasive Streptococcus pneumoniae isolates, from serotypes 11A, 15B/C and 23A (Not included in the conjugated vaccines), were collected in Colombia between 1994 and 2014, as part of the Network surveillance system for the causative agents of pneumonia and meningitis (SIREVA II). Objective. To determine the molecular typing of invasive S. pneumoniae isolates, from serotypes 11A, 15B/C and 23A, in Colombia from 1994 to 2014. Materials and methods. The molecular characterization of the isolates was carried out through pulse field gel electrophoresis (PFGE) and Multilocus Sequence Typing (MLST). Results. Serotype 11A showed one clonal group represented by ST62. Serotype 15B/C was composed of three groups associated with Netherlands15B-37 ST199 (28.75%), ST8495 (18.75.5%), and SLV (Single-Locus Variant) of ST193 (21.25%). Isolates from serotype 23A were gathered in three clonal groups, with 70.21% closely related to ST42, 17.02% to Colombia23F ST338, and 6.38% to Netherlands15B-37 ST199. Conclusion. Clones Colombia23F ST338 and Netherlands15B ST199 covered more serotypes than previously found by other authors, including the serotype 23A. These analyses reveal the importance of capsular switching for spreading successful clones between non-vaccine serotypes that cause invasive pneumococcal disease.