Banca de DEFESA: AISLA MÉRCIA LÁZARO DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : AISLA MÉRCIA LÁZARO DE OLIVEIRA
DATE: 17/12/2021
TIME: 09:00
LOCAL: Sistema RNP
TITLE:

MOLECULAR CHARACTERIZATION OF INVASIVE ISOLATES OF Streptococcus pneumoniae IDENTIFIED IN THE POST-VACCINE PERIOD

KEY WORDS:

Streptococcus pneumoniae, serotypes, invasive pneumococcal disease, vaccine

PAGES: 70
BIG AREA: Ciências Biológicas
AREA: Microbiologia
SUBÁREA: Microbiologia Aplicada
SPECIALTY: Microbiologia Médica
SUMMARY:

Streptococcus pneumoniae or pneumococcus, a gram-positive bacterium with 97 serotypes described, is one of the main causes of invasive infections that affect mainly children and the elderly, even though it is preventable by vaccines with good efficacy. In Brazil, the PCV10 conjugate vaccine that includes serotypes 1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F, and 23F is available in the national vaccination plan, which contributed to a reduction of more than 90% of cases of invasive infections caused by pneumococci. This study aimed to characterize the phenotypic and genotypic profiles of S. pneumoniae isolates from cases of invasive disease from 2010 to 2019 in
Salvador, Brazil. The isolates were obtained through the microbiological culture of different clinical specimens. The serotype was determined by multiplex PCR, the antimicrobial susceptibility profile was determined by disk diffusion method, and the clonal profile was obtained by PFGE and MLST. During the study period, we identify 226 cases of pneumococcal infection. Isolates were obtained from CSF (46.5%), blood (38.9%), CSF and blood (10.6%), pleural fluid (3.0%), tracheal aspirate (0.4%), and bronchoalveolar lavage (0.4%). When comparing the years 2010 and 2019, there was a reduction of 90.2% of cases of invasive pneumococcal disease (p=0.02). Most cases were due to non-vaccine serotypes, 67.3% (152/226), and the remaining were affected by vaccine serotypes, 32.7% (74/226). The most frequent serotypes were 14 (9.3%), 3 (8.8%), 23F (7.5%), 12F (6.2%) 19A (4.9%), 4 (4.4%), and 8 (4.4%). Male patients were more frequent (58.8%). The median age was 36 years [9-54, interquartile range 25-75%). Children aged 0-2 years (p<0.001) and 3-4 years (p=0.03) were more affected by pneumococcal infection by vaccine serotypes (14, 18C, 23F, and 6B), while adults aged 25-59 years were more affected by non-vaccine serotypes (12F, 19A, 3, and 8) (p=0.048). The antimicrobial susceptibility test showed that, of the included isolates, 23.9% (54/226) were not susceptible to penicillin, 22.1% (50/226) were not susceptible to sulfamethoxazole/trimethoprim, and 19.5% (44/226) were not susceptible to tetracycline. The vaccine serotypes 14, 19F, 23F, 18C were more resistant to penicillin (p>0.001) and to sulfamethoxazole/trimethoprim (p>0.001), while the non-vaccine serotypes 15C, 31, 19A were more resistant to erythromycin (p=0.02). Multidrug resistance was observed in 6.2% (14/226) of the isolates, and of these, 42.9% (6/14) were serotype 19A. Regarding the molecular analysis, three main clonal groups were observed, formed by ST66 (Serotype 14), ST218 (Serotype 12F), and ST193 (Serotype 18C). These findings reinforce the importance of continuous surveillance in cases of invasive disease caused by S. pneumoniae so that new epidemiological data are provided and help in evaluating the impact of the PCV10 vaccine in Brazil.

BANKING MEMBERS:
Presidente - 1187203 - JOICE NEVES REIS PEDREIRA
Interna - 3187360 - MARCIA CRISTINA AQUINO TEIXEIRA
Externo à Instituição - CÍCERO ARMÍDIO GOMES DIAS - UFCSPA