Publications by authors named "Lena Petrova Setchanova"
Haemophilus influenzae is one of the main bacteria responsible for otitis media (OM) among children worldwide. We aimed to estimate the distribution of encapsulated and non-capsulated variants (NTHi), biotypes, antibiotic susceptibility, and molecular epidemiology of H. influenzae isolates recovered from pediatric OM cases in Bulgaria.
View Article and Find Full Text PDFThe study aimed to evaluate the presence of pili in non-invasive pediatric pneumococcal isolates and to elucidate possible links with genetic lineages, serotypes, and antimicrobial resistance. We examined 147 Streptococcus pneumoniae isolates from children with respiratory tract infections and acute otitis media. Serotyping was performed by latex agglutination and capsule swelling reaction.
View Article and Find Full Text PDFStreptococcus pneumoniae is still a leading bacterial pathogen of acute otitis media (AOM), despite the availability of pneumococcal conjugate vaccines (PCVs). We conducted a study on the population structure, antibiotic nonsusceptibility, serotype distribution, and presence of pilus in middle ear fluids ‒ S. pneumoniae isolates recovered from PCV10-vaccinated children with suppurative АОМ in Bulgaria.
View Article and Find Full Text PDFGlobal Landscape Review of Serotype-Specific Invasive Pneumococcal Disease Surveillance among Countries Using PCV10/13: The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) Project.
Microorganisms
April 2021
Article Synopsis
- The PSERENADE project focuses on global surveillance of invasive pneumococcal disease (IPD) to assess the impact of pneumococcal conjugate vaccines (PCV10/13).
- Among 138 countries using PCV10/13 as of 2018, 109 had IPD surveillance systems, with data collected from 76, enabling a comprehensive analysis of 240,639 post-vaccine IPD cases.
- The dataset will aid in understanding the effectiveness of the vaccines across different demographics and vaccination schedules, influencing future immunization policies globally and nationally.
Article Synopsis
- The introduction of pneumococcal conjugate vaccines (PCVs) has significantly decreased the cases of pneumococcal meningitis, especially in countries that have used PCV10/13 for several years.
- A project called PSERENADE analyzed the types of pneumococcal strains still causing meningitis and found that certain serotypes, such as 19A and 6C, are still prevalent, particularly in older age groups.
- Current research on higher-valency PCVs could potentially address the remaining cases of pneumococcal meningitis, but further investigation is needed to understand their effectiveness in regions like the African meningitis belt.
Serogroup 6 remains common in the pneumococcal-conjugated vaccine era in Bulgaria; therefore, we investigated its clonal and serotype dynamics. The antibiotic susceptibilities were assessed by broth microdilution. Strains identified as serogroup 6 with latex agglutination method were subjected to serotype-specific PCRs.
View Article and Find Full Text PDFA pneumococcal conjugate vaccine (PCV10) was introduced in Bulgarian national immunization program since April 2010. Clonal composition based on pulsed-field gel electrophoresis and multilocus sequence typing genotyping of 52 serotype 19A Streptococcus pneumoniae isolates was analyzed. These were invasive and respiratory isolates collected between 1992 and 2013 from both children (78.
View Article and Find Full Text PDFObjective: To determine the serotypes, antimicrobial susceptibility, and beta-lactam resistance mechanisms of Haemophilus influenzae strains isolated from invasive and respiratory tract infections (RTIs) prior to the introduction of Haemophilus influenzae type b (Hib) vaccination in Bulgaria.
Methods: A total of 259 isolates were serotyped by polymerase chain reaction. Susceptibility to antibiotics and beta-lactamase production were determined, and DNA sequencing of the ftsI gene was performed for ampicillin non-susceptible strains.