Capsular genotype distribution of Group B Streptococcus colonization among at-risk pregnant women in Sao Paulo, Brazil

Author(s)

Kfouri, Renato de Avila ^[1] ; Campos Pignatari, Antonio Carlos ^[2] ; Ura Kusano, Elisa Junko ^[1] ; Rocchetti, Talita Trevizani ^[2] ; Fonseca, Clara Lopes ^[2] ; Weckx, Lily Yin ^[3]

Affiliation

^[1] Hosp & Maternidade Santa Joana, Sao Paulo, SP - Brazil

^[2] Univ Fed Sao Paulo, Dept Med, Sao Paulo, SP - Brazil

^[3] Univ Fed Sao Paulo, Dept Pediat, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Brazilian Journal of Infectious Diseases; v. 25, n. 3 MAY-JUN 2021.
• Web of Science Citations: 0

Abstract

Background: Vaccines in development against Group B Streptococcus (GBS) should contain the most prevalent capsular genotypes screened in the target population. In low- and middle-income countries epidemiological data on GBS carriage among pregnant women, a prerequisite condition for GBS neonatal sepsis, is needed to inform vaccine strategies. Objective: To investigate the prevalence of different GBS capsular genotypes that colonizes at-risk pregnant women in a private maternity hospital in Sao Paulo, Brazil. Methods: GBS strains isolated in routine maternity procedures from at-risk pregnant women from 2014 to 2018 were confirmed by mass spectrometry (MALDI-TOF) with subsequent DNA extraction for identification of capsular genotype through polymerase chain reaction (PCR). Demographic and gestational data were analyzed. Results: A total of 820 Todd-Hewitt broths positive for GBS were selected for streptococcal growth. Recovery and confirmation of GBS by MALDI-TOF were possible in 352. Strains were processed for determination of capsular genotype by PCR. From the total of 352 GBS isolates, 125 strains (35.5%) were genotyped as Ia; 23 (6.5%) as Ib; 41 (11.6%) as II; 36 (10.2%) as III; 4 (1.1%) as IV; 120 (34.1%) as V and 1 strain (0.3%) as VIII. Two isolates (0.7%) were not genotyped by used methodology. No statistically significant correlation between gestational risk factors, demographic data and distribution of capsular genotypes were found. Conclusions: GBS capsular genotypes Ia, Ib, II, III, and V were the most prevalent isolates colonizing at risk pregnant women in the present study. The inclusion of capsular genotypes Ia and V in the composition of future vaccines would cover 69.6% of capsular genotypes in the studied population. No statistically significant differences were observed between capsular genotype and gestational and demographic data and risk factors. (C) 2021 Sociedade Brasileira de Infectologia. Published by Elsevier Espana, S.L.U. (AU)

• FAPESP's process: 16/04708-6 - Group B serotypes prevalence at time of delivery in high-risk pregnant women in a private maternity in São Paulo
• Grantee: Lily Yin Weckx
• Support type: Regular Research Grants