Post-Vaccination Streptococcus pneumoniae Carriage and Virulence Gene Distribution among Children Less Than Five Years of Age, Cape Coast, Ghana

In 2012, Ghana introduced PCV13 into its childhood immunization program. To monitor the pneumococcus after PCV13 vaccination, we analyzed serotypes, antibiotic resistance, and virulence genes of pneumococcal carriage isolates among children under five years of age. We obtained nasopharyngeal swabs from 513 children from kindergartens and immunization centers in Cape Coast, Ghana. Pneumococcal serotypes were determined by multiplex-PCR and Quellung reaction. Antibiotic resistance and virulence genes prevalence were determined by disc diffusion and PCR respectively. Overall, carriage prevalence was 29.4% and PCV13 coverage was 38.4%. Over 60% of the isolates were non-PCV13 serotypes and serotype 23B was the most prevalent. One isolate showed full resistance to penicillin, while 35% showed intermediate resistance. Resistance to erythromycin and clindamycin remained low, while susceptibility to ceftriaxone, levofloxacin and vancomycin remained high. Penicillin resistance was associated with PCV13 serotypes. Forty-three (28.5%) strains were multidrug-resistant. Virulence genes pavB, pcpA, psrP, pilus-1, and pilus-2 were detected in 100%, 87%, 62.9%, 11.9%, and 6.6% of the strains, respectively. The pilus islets were associated with PCV13 and multidrug-resistant serotypes. PCV13 vaccination had impacted on pneumococcal carriage with a significant increase in non-PCV13 serotypes and lower penicillin resistance. Including PcpA and PsrP in pneumococcal protein-based vaccines could be beneficial to Ghanaian children.

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Characterisation of multidrug resistant Escherichia coli isolated from two commercial lettuce and spinach supply chains

Journal of Food Protection ◽

10.4315/jfp-21-125 ◽

2021 ◽

Author(s):

Muneiwa T. Ratshilingano ◽

Erika Margarete du Plessis ◽

Stacey Duvenage ◽

Lise Korsten

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Irrigation Water ◽

Virulence Genes ◽

Disease Outbreaks ◽

Virulence Gene ◽

Multidrug Resistant ◽

Water Sources ◽

Point Of Sale ◽

E Coli

ABSTRACT Leafy green vegetables have increasingly been reported as a reservoir of multidrug-resistant pathogenic Enterobacteriaceae; with Shiga toxin- producing Escherichia coli frequently implicated in disease outbreaks worldwide. This study aimed to determine the presence and characteristics of antibiotic resistance, diarrheagenic virulence genes and phylogenetic groupings of E. coli isolates (n=51) from commercially produced lettuce and spinach from the farm, through processing and at the point of sale. Multidrug resistance was observed in 33 of the 51 E. coli isolates (64.7%); with 35.7% (n=10/28) being generic and 100% (n=23/23) Extended Spectrum β-lactamase/AmpC- producing. Resistance of E. coli isolates was observed against neomycin (100%; n=51/51), ampicillin (70.6%; n=36/51), amoxycilin (68.6%; n=35/51), tetracycline (45%; n=23/51), trimethoprim/ sulfamethoxazole (43%; n=22/51), chloramphenicol (25.5%; n=13/51), augmentin (11.8%; n=6/51) and gentamicin (7.8%; n=4/51); with 100% (n=51/51) susceptibility to imipenem. Virulence gene eae was detected in two E. coli isolates from irrigation water sources only, while none of the other virulence genes tested for were detected. Most of the E. coli strains belonged to phylogenetic group B2 (25.5%; n=13), B1 (19.6%; n=10) and A (17.6%; n=9); with D (5.9%; n=3) less distributed. Although diarrheagenic E. coli were not detected, antibiotic resistance in E. coli prevalent in the supply chain was evident. Additionally, a clear link between E. coli isolates from irrigation water sources and leafy green vegetables through DNA fingerprinting was established which indicates the potential transfer of E. coli from irrigation water to minimally processed leafy green vegetables.

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Nasal Carriage in Vietnamese Children of Streptococcus pneumoniae Resistant to Multiple Antimicrobial Agents

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.3.484-488.2000 ◽

2000 ◽

Vol 44 (3) ◽

pp. 484-488 ◽

Cited By ~ 21

Author(s):

Christopher M. Parry ◽

To Song Diep ◽

John Wain ◽

Nguyen Thi Tuyet Hoa ◽

Mary Gainsborough ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Antimicrobial Agents ◽

Nasal Carriage ◽

Multidrug Resistant ◽

Penicillin Resistance ◽

Rural Children ◽

Asian Countries ◽

Pneumococcal Carriage ◽

Resistance To Penicillin ◽

A Prospective Study

ABSTRACT Resistance to antimicrobial agents in Streptococcus pneumoniae is increasing rapidly in many Asian countries. There is little recent information concerning resistance levels in Vietnam. A prospective study of pneumococcal carriage in 911 urban and rural Vietnamese children, of whom 44% were nasal carriers, was performed. Carriage was more common in children <5 years old than in those ≥5 years old (192 of 389 [49.4%] versus 212 of 522 [40.6%]; P, 0.01). A total of 136 of 399 isolates (34%) had intermediate susceptibility to penicillin (MIC, 0.1 to 1 mg/liter), and 76 of 399 isolates (19%) showed resistance (MIC, >1.0 mg/liter). A total of 54 of 399 isolates (13%) had intermediate susceptibility to ceftriaxone, and 3 of 399 isolates (1%) were resistant. Penicillin resistance was 21.7 (95% confidence interval, 7.0 to 67.6) times more common in urban than in rural children (35 versus 2%; P, <0.001). More than 40% of isolates from urban children were also resistant to erythromycin, trimethoprim-sulfamethoxazole, chloramphenicol, and tetracycline. Penicillin resistance was independently associated with an urban location when the age of the child was controlled for. Multidrug resistance (resistance to three or more antimicrobial agent groups) was present in 32% of isolates overall but in 39% of isolates with intermediate susceptibility to penicillin and 86% of isolates with penicillin resistance. The predominant serotypes of the S. pneumoniae isolates were 19, 23, 14, 6, and 18. Almost half of the penicillin-resistant isolates serotyped were serotype 23, and these isolates were often multidrug resistant. This study suggests that resistance to penicillin and other antimicrobial agents is common in carriage isolates of S. pneumoniae from children in Vietnam.

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Molecular characteristics and virulence gene profiles of Staphylococcus aureus isolates in Hainan, China

BMC Infectious Diseases ◽

10.1186/s12879-019-4547-5 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 8

Author(s):

Xuehan Li ◽

Tao Huang ◽

Kai Xu ◽

Chenglin Li ◽

Yirong Li

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Resistance Genes ◽

Virulence Genes ◽

Mainland China ◽

Geographical Location ◽

Antibiotic Resistance Genes ◽

Virulence Gene ◽

Molecular Characteristics ◽

Staphylococcal Protein A

Abstract Background There have been no reports regarding the molecular characteristics, virulence features, and antibiotic resistance profiles of Staphylococcus aureus (S. aureus) from Hainan, the southernmost province of China. Methods Two hundred twenty-seven S. aureus isolates, consisting of 76 methicillin-resistant S. aureus (MRSA) and 151 methicillin-susceptible S. aureus (MSSA), were collected in 2013–2014 and 2018–2019 in Hainan, and investigated for their molecular characteristics, virulence genes, antibiotic resistance profiles and main antibiotic resistance genes. Results Forty sequence types (STs) including three new STs (ST5489, ST5492 and ST5493), and 79 Staphylococcal protein A (spa) types were identified based on multilocus sequence typing (MLST) and spa typing, respectively. ST398 (14.1%, 32/227) was found to be the most prevalent, and the prevalence of ST398-MSSA increased significantly from 2013 to 2014 (5.5%, 5/91) to 2018–2019 (18.4%, 25/136). Seventy-six MRSA isolates were subject to staphylococcus chromosomal cassette mec (SCCmec) typing. SCCmec-IVa was the predominant SCCmec type, and specifically, ST45-SCCmec IVa, an infrequent type in mainland China, was predominant in S. aureus from Hainan. The antibiotic resistance profiles and antibiotic resistance genes of S. aureus show distinctive features in Hainan. The resistant rates of the MRSA isolates to a variety of antibiotics were significantly higher than those of the MSSA isolates. The predominant erythromycin and tetracycline resistance genes were ermC (90.1%, 100/111) and tetK (91.8%, 78/85), respectively. Eleven virulence genes, including the Panton-Valentine leukocidin (pvl) and eta, were determined, and the frequency of eta and pvl were found to be 57.3 and 47.6%. Such high prevalence has never been seen in mainland China before. Conclusion S. aureus isolates in Hainan have unique molecular characteristics, virulence gene and antibiotic resistance profiles, and main antibiotic resistance genes which may be associated with the special geographical location of Hainan and local trends in antibiotic use.

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Association among biofilm formation, virulence gene expression, and antibiotic resistance in Proteus mirabilis isolates from diarrhetic animals in northeast China

10.21203/rs.2.16502/v2 ◽

2020 ◽

Author(s):

Yadong Sun ◽

Shanshan Wen ◽

Lili Zhao ◽

Qiqi Xia ◽

Yue Pan ◽

...

Keyword(s):

Gene Expression ◽

Antibiotic Resistance ◽

Biofilm Formation ◽

Northeast China ◽

Virulence Gene ◽

Drug Susceptibility ◽

Multidrug Resistant ◽

Virulence Gene Expression ◽

Biofilm Production ◽

High Level

Abstract Background The aim of this study was to investigate the association among biofilm formation, virulence gene expression, and antibiotic resistance in P. mirabilis isolates collected from diarrhetic animals (n = 176) in northeast China between September 2014 and October 2016. Results Approximately 92.05% of the isolates were biofilm producers, whereas 7.95% of the isolates were non-producers. The prevalence of virulence genes in biofilm producers was significantly higher than that in non-producers. Biofilm production was significantly associated with the expression of ureC , zapA , rsmA , hmpA , mrpA , atfA , and pmfA ( P < 0.05). Drug susceptibility tests revealed that approximately 76.7% of the isolates were multidrug-resistant (MDR) and extensively drug-resistant (XDR). Biofilm production was significantly associated with resistance to doxycycline, tetracycline, sulfamethoxazole, kanamycin, and cephalothin ( P < 0.05). Although the pathogenicity of the biofilm producers was stronger than that of the non-producers, the biofilm-forming ability of the isolates was not significantly associated with morbidity and mortality in mice ( P > 0.05). Conclusion Our findings suggested that a high level of multidrug resistance in diarrhetic animals infected with P. mirabilis in northeast China.The results of this study indicated that the positive rates of the genes expressed by biofilm-producing P. mirabilis isolates were significantly higher than those expressed by non-producing isolates.

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Prevalence of Virulence Genes and Drug Resistance Profiles of Pseudomonas aeruginosa Isolated From Clinical Specimens

Jundishapur Journal of Microbiology ◽

10.5812/jjm.118452 ◽

2021 ◽

Vol 14 (8) ◽

Author(s):

Seyed Ali Bazghandi ◽

Mohsen Arzanlou ◽

Hadi Peeridogaheh ◽

Hamid Vaez ◽

Amirhossein Sahebkar ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Drug Resistance ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Virulence Gene ◽

Clinical Isolates ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Clinical Specimens ◽

Resistance Rates

Background: Drug resistance and virulence genes are two key factors for the colonization of Pseudomonas aeruginosa in settings with high antibiotic pressure, such as hospitals, and the development of hospital-acquired infections. Objectives: The objective of this study was to investigate the prevalence of drug resistance and virulence gene profiles in clinical isolates of P. aeruginosa in Ardabil, Iran. Methods: A total of 84 P. aeruginosa isolates were collected from clinical specimens of Ardabil hospitals and confirmed using laboratory standard tests. The disk diffusion method was used for antibiotic susceptibility testing and polymerase chain reaction (PCR) for the identification of P. aeruginosa virulence genes. Results: The highest and the lowest antibiotic resistance rates of P. aeruginosa strains were against ticarcillin-clavulanate (94%) and doripenem (33.3%), respectively. In addition, the frequency of multidrug-resistant (MDR) P. aeruginosa was 55.9%. The prevalence of virulence factor genes was as follows: algD 84.5%, lasB 86.9%, plcH 86.9%, plcN 86.9%, exoU 56%, exoS 51.2%, toxA 81%, nan1 13.1%, and pilB 33.3%. A significant association was observed between resistance to some antibiotics and the prevalence of virulence genes in P. aeruginosa. Conclusions: Our results revealed a high prevalence of antibiotic resistance, especially MDR, and virulence-associated genes in clinical isolates of P. aeruginosa in Ardabil hospitals. Owing to the low resistance rates against doripenem, gentamicin, and tobramycin, these antibiotics are recommended for the treatment of infections caused by highly resistant and virulent P. aeruginosa strains.

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Occurrence of virulent multidrug-resistantEnterococcus faecalisandEnterococcus faeciumin the pigs, farmers and farm environments in Malaysia

PeerJ ◽

10.7717/peerj.5353 ◽

2018 ◽

Vol 6 ◽

pp. e5353 ◽

Cited By ~ 6

Author(s):

Shiang Chiet Tan ◽

Chun Wie Chong ◽

Cindy Shuan Ju Teh ◽

Peck Toung Ooi ◽

Kwai Lin Thong

Keyword(s):

Polymerase Chain Reaction ◽

Antibiotic Resistance ◽

Environmental Factors ◽

Environmental Samples ◽

Virulence Genes ◽

Multidrug Resistant ◽

Peninsular Malaysia ◽

Chain Reaction ◽

Swine Farms ◽

Polymerase Chain

BackgroundEnterococcus faecalisandEnterococcus faeciumare ubiquitous opportunistic pathogens found in the guts of humans and farmed animals. This study aimed to determine the occurrence, antimicrobial resistance, virulence, biofilm-forming ability and genotypes ofE. faecalisandE. faeciumfrom swine farms. Correlations between the genotypes, virulotypes, antibiotic resistance, and the environmental factors such as locality of farms and farm hygiene practice were explored.MethodsE. faecalisandE. faeciumstrains were isolated from the oral, rectal and fecal samples of 140 pigs; nasal, urine and fecal samples of 34 farmers working in the farms and 42 environmental samples collected from seven swine farms located in Peninsular Malaysia. Antibiotic susceptibility test was performed using the disk diffusion method, and the antibiotic resistance and virulence genes were detected by Polymerase Chain Reaction. Repetitive Extragenic Palindromic-Polymerase Chain Reaction and Pulsed-Field Gel Electrophoresis were performed to determine the clonality of the strains. Crosstab/Chi-square test and DistLM statistical analyses methods were used to determine the correlations between the genotypes, virulence factors, antibiotic resistance, and the environmental factors.ResultsA total of 211E. faecalisand 42E. faeciumwere recovered from 140 pigs, 34 farmers and 42 environmental samples collected from seven swine farms in Peninsular Malaysia. Ninety-eight percent of the strains were multidrug-resistant (resistant to chloramphenicol, tetracycline, ciprofloxacin and erythromycin). Fifty-two percent of the strains formed biofilms. Virulence genesefa, asaI, gelE,esp,cylandacegenes were detected. Virulence genesefaandasaI were most prevalent inE. faecalis(90%) andE. faecium(43%), respectively. Cluster analyses based on REP-PCR and PFGE showed the strains were genetically diverse. Overall, the strains isolated from pigs and farmers were distinct, except for three highly similar strains found in pigs and farmers. The strains were regional- and host-specific.DiscussionThis study revealed alarming high frequencies of multidrug-resistant enterococci in pigs and swine farmers. The presence of resistance and virulence genes and the ability to form biofilm further enhance the persistence and pathogenicity of the strains. Although the overall clonality of the strains were regionals and host-specific, strains with high similarity were found in different hosts. This study reiterates a need of a more stringent regulation to ensure the proper use of antibiotics in swine husbandry to reduce the wide spread of multidrug-resistant strains.

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Antibiotic Resistance and Virulence Gene Characteristics of Methicillin-Resistant Staphylococcus aureus (MRSA) Isolated from Healthy Edible Marine Fish

International Journal of Microbiology ◽

10.1155/2020/9803903 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Justine Fri ◽

Henry A. Njom ◽

Collins N. Ateba ◽

Roland N. Ndip

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Marine Fish ◽

Control Strategies ◽

Virulence Gene ◽

Multidrug Resistant ◽

Methicillin Resistant ◽

Vancomycin Mics ◽

Resistant Strains ◽

Mrsa Strains

Thirty-three (33) isolates of methicillin-resistant Staphylococcus aureus (MRSA) from healthy edible marine fish harvested from two aquaculture settings and the Kariega estuary, South Africa, were characterised in this study. The phenotypic antimicrobial susceptibility profiles to 13 antibiotics were determined, and their antibiotic resistance determinants were assessed. A multiplex PCR was used to determine the epidemiological groups based on the type of SCCmec carriage followed by the detection of staphylococcal enterotoxin-encoding genes sea-sed and the Panton Valentine leucocidin gene (pvl). A high antibiotic resistance percentage (67–81%) was observed for Erythromycin, Ampicillin, Rifampicin, and Clindamycin, while maximum susceptibility to Chloramphenicol (100%), Imipenem (100%), and Ciprofloxacin (94%) was recorded. Nineteen (58%) of the MRSA strains had Vancomycin MICs of ≤2 μg/mL, 4 (12%) with MICs ranging from 4–8 μg/mL, and 10 (30%) with values ≥16 μg/mL. Overall, 27 (82%) isolates were multidrug-resistant (MDR) with Erythromycin-Ampicillin-Rifampicin-Clindamycin (E-AMP-RIP-CD) found to be the dominant antibiotic-resistance phenotype observed in 4 isolates. Resistance genes such as tetM, tetA, ermB, blaZ, and femA were detected in two or more resistant strains. A total of 19 (58%) MRSA strains possessed SCCmec types I, II, or III elements, characteristic of healthcare-associated MRSA (HA-MRSA), while 10 (30%) isolates displayed SCCmec type IVc, characteristic of community-associated MRSA (CA-MRSA). Six (18%) of the multidrug-resistant strains of MRSA were enterotoxigenic, harbouring the see, sea, or sec genes. A prevalence of 18% (6/33) was also recorded for the luk-PVL gene. The findings of this study showed that marine fish contained MDR-MRSA strains that harbour SCCmec types, characteristic of either HA-MRSA or CA-MRSA, but with a low prevalence of enterotoxin and pvl genes. Thus, there is a need for continuous monitoring and implementation of better control strategies within the food chain to minimise contamination of fish with MDR-MRSA and the ultimate spread of the bug.

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Detection of Virulence Genes in Multidrug Resistant Enterococci Isolated from Feedlots Dairy and Beef Cattle: Implications for Human Health and Food Safety

BioMed Research International ◽

10.1155/2019/5921840 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 5

Author(s):

Frank Eric Tatsing Foka ◽

Collins Njie Ateba

Keyword(s):

Public Health ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Efflux Pump ◽

Health Sector ◽

Multidrug Resistant ◽

North West ◽

The North ◽

Vancomycin Resistant ◽

The Impact

The misuse/abuse of antibiotics in intensive animal rearing and communities led to the emergence of resistant isolates such as vancomycin-resistant enterococci (VREs) worldwide. This has become a major source of concern for the public health sector. The aim of this study was to report the antibiotic resistance profiles and to highlight the presence of virulence genes in VREs isolated from feedlots cattle of the North-West Province of South Africa. 384 faecal samples, 24 drinking troughs water, and 24 soil samples were collected aseptically from 6 registered feedlots. Biochemical and molecular methods were used to identify and categorise the enterococci isolates. Their antibiotic resistance profiles were assessed and genotypic methods were used to determine their antibiotic resistance and their virulence profiles. 527 presumptive isolates were recovered, out of which 289 isolates were confirmed asEnterococcussp. Specifically,E. faecalis(9%),E. faecium(10%),E. durans(69%),E. gallinarum(6%),E. casseliflavus(2%),E. mundtii(2%), andE. avium(2%) were screened after molecular assays.VanA(62%),vanB(17%), andvanC(21%) resistance genes were detected in 176Enterococcussp., respectively. Moreover,tetK(26),tetL(57),msrA/B(111), andmefA(9) efflux pump genes were detected in 138 VRE isolates.Multiple antibiotic resistances were confirmed in all the VRE isolates of this study; the most common antibiotic resistance phenotype wasTETR-AMPR-AMXR-VANR-PENR-LINR-ERYR.CylA,hyl,esp,gelE, andasa1virulence genes were detected in 86 VREs with the exception of vancomycin-resistantE. mundtiiisolates that did not display any virulence factor. Most VRE isolates had more than one virulence genes but the most encountered virulence profile wasgelE-hyl. Potentially pathogenic multidrug resistant VREs were detected in this study; this highlights the impact of extensive usage of antimicrobials in intensive animal rearing and its implications on public health cannot be undermined.

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Molecular detection of biofilm, virulence and antimicrobial resistance associated genes of Salmonella serovars isolated from pig and chicken of Mizoram, India

Indian Journal of Animal Research ◽

10.18805/ijar.b-3817 ◽

2019 ◽

Author(s):

S. Chakraborty ◽

P. Roychoudhury ◽

I. Samanta ◽

P. K. Subudhi ◽

Lalhruaipuii Lalhruaipuii ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Virulence Genes ◽

Antimicrobial Agents ◽

Virulence Gene ◽

Microtiter Plate ◽

Multidrug Resistant ◽

Salmonella Spp ◽

Microtiter Plate Assay ◽

Antimicrobial Sensitivity ◽

Salmonella Infections

Salmonella has emerged as one of the most important food-borne pathogens for humans as well as animals and the ability of biofilm formation by these bacteria has further aided their survival in unfavorable environment. Characterization of these biofilm producing bacteria isolated from pigs and chicken may lead to formulation of strategies for prevention and control of Salmonella infections. Therefore, the present study was conducted to isolate Salmonella from pigs and poultry of Mizoram, determine their biofilm producing ability by phenotypic and genotypic methods along with their virulence and antimicrobial resistance properties. A total of 15 Salmonella spp. (pig=9, poultry=6) was isolated from 100 faecal samples from pigs and 50 cloacal swabs from poultry and biofilm producing ability of the isolates was determined by microtiter plate assay. A total of 10 (66.67%) isolates were found to be biofilm producer. All the biofilm producing bacterial isolates were investigated for antimicrobial sensitivity and distribution of selected biofilm associated genes (csgA, csgD and adrA), virulence genes (invA, stn and sefA) and antimicrobial resistance (AMR) genes (blaTEM, blaSHV and blaCTX-M). The most prevalent resistance was found against ceftazidime (80%), ceftriaxone (80%), cefixime (70%), cefotaxime (70%), gentamicin (70%), cotrimoxazole (60%) and ampicillin (60%). A total of 7 (70%) isolates were resistant to at least three different classes of antimicrobial agents and considered as multidrug resistant. All the isolates were positive for adrA (100%) but negative for csgA and csgD genes. The most frequent virulence gene was invA (100%) and stn (100%). Among the AMR genes, blaTEM (60%) was found to be the major AMR determinants. Moreover, a total of 7 Salmonella isolates were positive for at least one of t biofilm associated genes, virulence genes and AMR genes.

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Analysis of virulence factors and antibiotic resistance genes in Group B Streptococcus from clinical samples

10.21203/rs.2.21004/v1 ◽

2020 ◽

Author(s):

Raymond Mudzana ◽

Rooyen T Mavenyengwa ◽

Muchaneta Gudza-Mugabe

Keyword(s):

Antibiotic Resistance ◽

Pregnant Women ◽

Virulence Factors ◽

Resistance Genes ◽

Virulence Genes ◽

Group B Streptococcus ◽

Antibiotic Resistance Genes ◽

Virulence Gene ◽

Clinical Samples ◽

Group B

Abstract Background: Streptococcus agalacticae is one of the most important causative agents of serious infections among neonates. Group B Streptococcus (GBS) virulence factors are important in the development of vaccines, whilst antibiotic resistance genes are necessary in understanding the resistance mechanisms used by these pathogens. This study was carried out to identify the virulence genes and antibiotic resistance genes associated with GBS isolated from pregnant women.Methods: A total of 43 GBS isolates were obtained from vaginal samples that were collected from all HIV positive and HIV negative women who were 13-35 weeks pregnant attending Antenatal Care at both 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 in the isolates. Data was fed into SPSS 24.0 and the Spearman rank correlation test used to determine any 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 among GBS isolates. 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). Antibiotic resistance genes 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 amplification yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded a low 9.3% (4/43).Conclusion: The study showed a 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.

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