Background Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. This study was carried out to identify antibiotic resistance and virulence genes associated with GBS isolated from pregnant women. Methods A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13–35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods and molecular identification testing. Antibiotic susceptibility testing was done using the modified Kirby-Bauer method and E-test strips. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0. Results Nine distinct virulence gene profiles were identified and hly-scpB-bca-rib 37.2% (16/43) was common. The virulence genes identified were namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by 72.1% (31/43) cefazolin, 69.8% (30/43) penicillin G, 58.1% (25/43) ampicillin, 55.8% (24/43) clindamycin, 46.5% (20/43) ceftriaxone, 34.9% (15/43) chloramphenicol, and 30.2% (13/43) for both erythromycin and vancomycin using disk diffusion. Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43). Conclusion The study showed high prevalence of hly, scpB, bca and rib virulence genes in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. Multi-drug resistance coupled with the recovery of resistant isolates to antimicrobial agents such as penicillins indicates the importance of GBS surveillance and susceptibility tests. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

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Background : Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. GBS virulence factors are important in vaccine development, whilst antibiotic resistance genes are necessary in understanding the resistance mechanisms used by pathogens. This study was carried out to identify virulence genes and antibiotic resistance genes associated with GBS isolated from pregnant women. Methods: A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods including molecular tests. Antibiotic susceptibility testing using 3 antibiotics was done using the modified Kirby-Bauer method. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0 and the Spearman rank correlation test used to determine correlation among genes. Results: Nine distinct virulence gene profiles were identified. The profiles hly-scpB-bca-rib 37.2% (16/43) and hly-scpB-bca 18.6% (8/43) were common. The following virulence gene frequencies were obtained namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by clindamycin 55.8% (24/43) and erythromycin 30.2% (13/43). Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43). Conclusion: The study showed high prevalence of multiple virulence genes hly, scpB, bca and rib in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was found to be predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

Background: Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. This study was carried out to identify antibiotic resistance and virulence genes associated with GBS isolated from pregnant women. Methods: A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods and molecular identification testing. Antibiotic susceptibility testing was done using the modified Kirby-Bauer method. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0 and the Spearman rank correlation test used to determine correlation among genes. Results: Nine distinct virulence gene profiles were identified. The profiles hly-scpB-bca-rib 37.2% (16/43) and hly-scpB-bca 18.6% (8/43) were common. The virulence genes identified were namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by penicillin G, 69.8% (30/43), ampicillin 58.1% (25/43), clindamycin 55.8% (24/43) and erythromycin 30.2% (13/43). Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43). Conclusion: The study showed a high prevalence of hly, scpB, bca and rib virulence genes in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was found to be predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. The recovery of resistant isolates to antimicrobial agents such as penicillins indicates the importance of GBS surveillance and susceptibility tests. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

Background: Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. This study was carried out to identify antibiotic resistance and virulence genes associated with GBS isolated from pregnant women.Methods: A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods and molecular identification testing. Antibiotic susceptibility testing was done using the modified Kirby-Bauer method and E-test strips. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0.Results: Nine distinct virulence gene profiles were identified and hly-scpB-bca-rib 37.2% (16/43) was common. The virulence genes identified were namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by 72.1% (31/43) cefazolin, 69.8% (30/43) penicillin G, 58.1% (25/43) ampicillin, 55.8% (24/43) clindamycin, 46.5% (20/43) ceftriaxone, 34.9% (15/43) chloramphenicol, and 30.2% (13/43) for both erythromycin and vancomycin using disk diffusion. Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43).Conclusion: The study showed high prevalence of hly, scpB, bca and rib virulence genes in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. Multi-drug resistance coupled with the recovery of resistant isolates to antimicrobial agents such as penicillins indicates the importance of GBS surveillance and susceptibility tests. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

Background: Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. This study was carried out to identify antibiotic resistance and virulence genes associated with GBS isolated from pregnant women.Methods: A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods and molecular identification testing. Antibiotic susceptibility testing was done using the modified Kirby-Bauer method and E-test strips. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0.Results: Nine distinct virulence gene profiles were identified and hly-scpB-bca-rib 37.2% (16/43) was common. The virulence genes identified were namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by 72.1% (31/43) cefazolin, 69.8% (30/43) penicillin G, 58.1% (25/43) ampicillin, 55.8% (24/43) clindamycin, 46.5% (20/43) ceftriaxone, 34.9% (15/43) chloramphenicol, and 30.2% (13/43) for both erythromycin and vancomycin using disk diffusion. Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43).Conclusion: The study showed high prevalence of hly, scpB, bca and rib virulence genes in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. Multi-drug resistance coupled with the recovery of resistant isolates to antimicrobial agents such as penicillins indicates the importance of GBS surveillance and susceptibility tests. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

Background: Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. This study was carried out to identify antibiotic resistance and virulence genes associated with GBS isolated from pregnant women.Methods: A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods and molecular identification testing. Antibiotic susceptibility testing was done using the modified Kirby-Bauer method and E-test strips. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0.Results: Nine distinct virulence gene profiles were identified and hly-scpB-bca-rib 37.2% (16/43) was common. The virulence genes identified were namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by 72.1% (31/43) cefazolin, 69.8% (30/43) penicillin G, 58.1% (25/43) ampicillin, 55.8% (24/43) clindamycin, 46.5% (20/43) ceftriaxone, 34.9% (15/43) chloramphenicol, and 30.2% (13/43) for both erythromycin and vancomycin using disk diffusion. Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43).Conclusion: The study showed high prevalence of hly, scpB, bca and rib virulence genes in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. Multi-drug resistance coupled with the recovery of resistant isolates to antimicrobial agents such as penicillins indicates the importance of GBS surveillance and susceptibility tests. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

Background: Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. This study was carried out to identify antibiotic resistance and virulence genes associated with GBS isolated from pregnant women.Methods: A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods and molecular identification testing. Antibiotic susceptibility testing was done using the modified Kirby-Bauer method and E-test strips. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0.Results: Nine distinct virulence gene profiles were identified and hly-scpB-bca-rib 37.2% (16/43) was common. The virulence genes identified were namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by 72.1% (31/43) cefazolin, 69.8% (30/43) penicillin G, 58.1% (25/43) ampicillin, 55.8% (24/43) clindamycin, 46.5% (20/43) ceftriaxone, 34.9% (15/43) chloramphenicol, and 30.2% (13/43) for both erythromycin and vancomycin using disk diffusion. Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43).Conclusion: The study showed high prevalence of hly, scpB, bca and rib virulence genes in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. Multi-drug resistance coupled with the recovery of resistant isolates to antimicrobial agents such as penicillins indicates the importance of GBS surveillance and susceptibility tests. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.