Genotypic Characterization of Clinical Isolates of Staphylococcus aureus from Pakistan

In this study, we compared pulsed-field gel electrophoretic (PFGE), multilocus sequence typing (MLST), Staphylococcal cassette chromosome mec (SCCmec), spa typing, and virulence gene profiles of 19 Panton–Valentine leucocidin (PVL)-positive, multidrug-, and methicillin-resistant clinical Staphylococcus aureus (MRSA) isolates obtained from a hospital intensive care unit in Pakistan. The isolates exhibited 10 pulsotypes, contained eight adhesin genes (bbp, clfA, clfB, cna, fnbA, fnbB, map-eap, and spa), 10 toxin genes (hla, hlb, hld, hlg, pvl, sed, see, seg, seh, and tst), and two other virulence genes (cfb, v8) that were commonly present in all isolates. The spa-typing indicated seven known spa types (t030, t064, t138, t314, t987, t1509, and t5414) and three novel spa types. MLST analysis indicated eight ST types (ST8, ST15, ST30, ST239, ST291, ST503, ST772, and ST1413). All isolates belonged to the agr group 1. Most of the isolates possessed SCCmec type III, but some isolates had it in combination with types SCCmec IV and V. The presence of multidrug-resistant MRSA isolates in Pakistan indicates poor hygienic conditions, overuse of antibiotics, and a lack of rational antibiotic therapy that have led to the evolution and development of hypervirulent MRSA clones. The study warrants development of a robust epidemiological screening program and adoption of effective measures to stop their spread in hospitals and the community.

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

10.21203/rs.2.10997/v1 ◽

2019 ◽

Author(s):

Xuehan Li ◽

Kai Xu ◽

Chenglin Li ◽

Tao Huang ◽

Yirong Li

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Sccmec Type ◽

Mainland China ◽

Virulence Gene ◽

Molecular Characteristics ◽

Spa Typing ◽

Gene Profiles ◽

High Prevalence

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: 227 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, and antibiotic resistance profiles. Results: Thirty-four sequence types (STs) and 79 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 moreover, the prevalence of ST398-MSSA increased significantly from 2013-2014 (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. Eleven virulence genes, including the Panton-Valentine leukocidin (pvl) and eta, were determined, and the positive rates of eta and pvl were found to be 57.3% and 47.6%. Such high prevalence has never been seen in mainland China before.

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Nasopharyngeal carriage, spa types and antibiotic susceptibility profiles of Staphylococcus aureus from healthy children less than 5 years in Eastern Uganda

10.21203/rs.2.10945/v4 ◽

2019 ◽

Author(s):

David Kateete ◽

Benon B Asiimwe ◽

Raymond Mayanja ◽

Brian Mujuni ◽

Freddie Bwanga ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Low Income ◽

Antibiotic Susceptibility ◽

Multidrug Resistant ◽

Healthy Children ◽

Beta Lactam ◽

Spa Typing ◽

Carriage Rate ◽

Eastern Uganda ◽

Spa Types

Abstract Background: Staphylococcus aureus carriage is a known risk factor for staphylococcal disease. However, the carriage rates vary by country, demographic group and profession. This study aimed to determine the S. aureus carriage rate in children in Eastern Uganda, and identify S. aureus lineages that cause infection in Uganda. Methods: Nasopharyngeal samples from 742 healthy children less than 5 years residing in the Iganga/Mayuge Health & Demographic Surveillance Site in Eastern Uganda were processed for isolation of S. aureus. Antibiotic susceptibility testing based on minimum inhibitory concentrations (MICs) was determined by the BD PhoenixTM system. Genotyping was performed by spa typing. Results: The processed samples yielded 144 S. aureus isolates (one per child) therefore, the S. aureus carriage rate in children was 19.4% (144/742). Thirty one percent (45/144) of the isolates were methicillin resistant (MRSA) yielding a carriage rate of 6.1% (45/742). All isolates were susceptible to rifampicin, vancomycin and linezolid. Moreover, all MRSA were susceptible to vancomycin, linezolid and clindamycin. Compared to methicillin susceptible S. aureus (MSSA) isolates (68.8%, 99/144), MRSA isolates were more resistant to non-beta-lactam antimicrobials –trimethoprim/sulfamethoxazole 73.3% (33/45) vs. 27.3% (27/99) [P<0.0001]; erythromycin 75.6% (34/45) vs. 24.2% (24/99) [P<0.0001]; chloramphenicol 60% (27/45) vs. 19.2% (19/99) [P<0.0001]; gentamicin 55.6% (25/45) vs. 25.3% (25/99) [P=0.0004]; and ciprofloxacin 35.6% (16/45) vs. 2% (2/99) [P<0.0001]. Furthermore, 42 MRSA (93.3%) were multidrug resistant (MDR) and one exhibited high-level resistance to mupirocin. Overall, 61 MSSA (61.6%) were MDR, including three mupirocin and clindamycin resistant isolates. Seven spa types were detected in MRSA, of which t037 & t064 were predominant and associated with SCCmec types I & IV, respectively. Fourteen spa types were detected in MSSA, of which t645 & t4353 were predominant. Conclusions: S. aureus carriage rate in healthy children in Eastern Uganda is high and comparable to rates for hospitalized patients in Kampala. The detection of mupirocin resistance is worrying as it could rapidly increase if mupirocin is administered in a low-income setting. S. aureus strains of spa types t064, t037 (MRSA) and t645, t4353 (MSSA) are prevalent and could be responsible for majority of staphylococcal infections in Uganda.

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Genotypic Characteristics and Correlation of Epidemiology of Staphylococcus aureus in Healthy Pigs, Diseased Pigs, and Environment

Antibiotics ◽

10.3390/antibiotics9120839 ◽

2020 ◽

Vol 9 (12) ◽

pp. 839

Author(s):

Yuanyuan Zhou ◽

Xinhui Li ◽

He Yan

Keyword(s):

Staphylococcus Aureus ◽

Large Scale ◽

Susceptibility Testing ◽

Multidrug Resistant ◽

Spa Typing ◽

Antimicrobial Resistance Gene ◽

Resistance To Penicillin ◽

Genotypic Characteristics ◽

Sequence Types ◽

Spa Types

China is one of the largest producers of pigs and pork in the world. However, large-scale studies on pig-associated Staphylococcus aureus in relation to healthy pigs, diseased pigs and environment are scarce. The objective of the present study was to characterize and compare S. aureus isolates from healthy pigs, diseased pigs and environment through antimicrobial susceptibility testing, multiple locus sequence typing, spa typing, and antimicrobial resistance gene screening. Results showed all isolates were susceptible to linezolid and vancomycin. However, 66.7% (104/156) isolates were multidrug-resistant by displaying resistance to three or more antibiotics and high rates of resistance to penicillin, tetracycline, clindamycin, and clarithromycin were observed. Of the 20 multilocus sequence types (STs) identified among the isolates, ST9, ST188, and ST7 were most commonly isolated from healthy pigs and environment, while ST1 was most commonly isolated from diseased pigs. In total, 17 spa types were represented among the isolates, while t4792 was most commonly isolated from diseased pigs and t899, t189 were most commonly isolated from healthy pigs and environment. In conclusion, the genotypic and epidemiology characteristics observed among the isolates suggest pigs and pork could be important players in S. aureus dissemination.

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Antibiotic Resistance, spa Typing and Clonal Analysis of Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates from Blood of Patients Hospitalized in the Czech Republic

Antibiotics ◽

10.3390/antibiotics10040395 ◽

2021 ◽

Vol 10 (4) ◽

pp. 395

Author(s):

Katarina Pomorska ◽

Vladislav Jakubu ◽

Lucia Malisova ◽

Marta Fridrichova ◽

Martin Musilek ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Czech Republic ◽

Methicillin Resistant Staphylococcus Aureus ◽

Bloodstream Infections ◽

Spa Typing ◽

The Czech Republic ◽

Methicillin Resistant ◽

Mrsa Strains ◽

Spa Types ◽

Repeat Pattern

Staphylococcus aureus is one of the major causes of bloodstream infections. The aim of our study was to characterize methicillin-resistant Staphylococcus aureus (MRSA) isolates from blood of patients hospitalized in the Czech Republic between 2016 and 2018. All MRSA strains were tested for antibiotic susceptibility, analyzed by spa typing and clustered using a Based Upon Repeat Pattern (BURP) algorithm. The representative isolates of the four most common spa types and representative isolates of all spa clonal complexes were further typed by multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing. The majority of MRSA strains were resistant to ciprofloxacin (94%), erythromycin (95.5%) and clindamycin (95.6%). Among the 618 strains analyzed, 52 different spa types were detected. BURP analysis divided them into six different clusters. The most common spa types were t003, t586, t014 and t002, all belonging to the CC5 (clonal complex). CC5 was the most abundant MLST CC of our study, comprising of 91.7% (n = 565) of spa-typeable isolates. Other CCs present in our study were CC398, CC22, CC8, CC45 and CC97. To our knowledge, this is the biggest nationwide study aimed at typing MRSA blood isolates from the Czech Republic.

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The First Report of a Methicillin-Resistant Staphylococcus aureus Isolate Harboring Type IV SCCmec in Thailand

Pathogens ◽

10.3390/pathogens10040430 ◽

2021 ◽

Vol 10 (4) ◽

pp. 430

Author(s):

Wichai Santimaleeworagun ◽

Praewdow Preechachuawong ◽

Wandee Samret ◽

Tossawan Jitwasinkul

Keyword(s):

Staphylococcus Aureus ◽

Resistance Genes ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Sccmec Type ◽

Clinical Strain ◽

Spa Typing ◽

Methicillin Resistant ◽

Type Iv ◽

Antimicrobial Resistance Genes

Methicillin-resistant Staphylococcus aureus (MRSA) is mostly found in Thailand in the hospital as a nosocomial pathogen. This study aimed to report the genetic characterization of a clinical community-acquired MRSA (CA-MRSA) isolate collected from hospitalized patients in Thailand. Among 26 MRSA isolates, S. aureus no. S17 preliminarily displayed the presence of a staphylococcal cassette chromosome mec (SCCmec) type IV pattern. The bacterial genomic DNA was subjected to whole-genome sequencing. Panton–Valentine leukocidin (PVL) production, virulence toxins, and antibiotic resistance genes were identified, and multi-locus sequence typing (MLST) and spa typing were performed. The strain was matched by sequence to MLST type 2885 and spa type t13880. This strain carried type IV SCCmec with no PVL production. Five acquired antimicrobial resistance genes, namely blaZ, mecA, Inu(A), tet(K), and dfrG conferring resistance to β-lactams, lincosamides, tetracycline, and trimethoprim, were identified. The detected toxins were exfoliative toxin A, gamma-hemolysin, leukocidin D, and leukocidin E. Moreover, there were differences in seven regions in CR-MRSA no. S17 compared to CA-MRSA type 300. In summary, we have reported the ST2885-SCCmec IV CA-MRSA clinical strain in Thailand for the first time, highlighting the problem of methicillin resistance in community settings and the consideration in choosing appropriate antibiotic therapy.

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Lack of correlation of virulence gene profiles of Staphylococcus aureus bacteremia isolates with mortality

Microbial Pathogenesis ◽

10.1016/j.micpath.2019.103543 ◽

2019 ◽

Vol 133 ◽

pp. 103543 ◽

Cited By ~ 2

Author(s):

Kyung-Hwa Park ◽

Kerryl E. Greenwood-Quaintance ◽

Scott A. Cunningham ◽

Govindarajan Rajagopalan ◽

Nicholas Chia ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Virulence Gene ◽

Staphylococcus Aureus Bacteremia ◽

Gene Profiles

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Staphylococcus aureus Infections in Malaysia: A Review of Antimicrobial Resistance and Characteristics of the Clinical Isolates, 1990–2017

Antibiotics ◽

10.3390/antibiotics8030128 ◽

2019 ◽

Vol 8 (3) ◽

pp. 128 ◽

Cited By ~ 3

Author(s):

Ainal Mardziah Che Hamzah ◽

Chew Chieng Yeo ◽

Suat Moi Puah ◽

Kek Heng Chua ◽

Ching Hoong Chew

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Resistance ◽

Sccmec Type ◽

Epidemiological Data ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Type Iv ◽

Resistant Strains ◽

Vancomycin Resistant ◽

Comprehensive Surveillance

Staphylococcus aureus is an important nosocomial pathogen and its multidrug resistant strains, particularly methicillin-resistant S. aureus (MRSA), poses a serious threat to public health due to its limited therapeutic options. The increasing MRSA resistance towards vancomycin, which is the current drug of last resort, gives a great challenge to the treatment and management of MRSA infections. While vancomycin resistance among Malaysian MRSA isolates has yet to be documented, a case of vancomycin resistant S. aureus has been reported in our neighboring country, Indonesia. In this review, we present the antimicrobial resistance profiles of S. aureus clinical isolates in Malaysia with data obtained from the Malaysian National Surveillance on Antimicrobial Resistance (NSAR) reports as well as various peer-reviewed published records spanning a period of nearly three decades (1990–2017). We also review the clonal types and characteristics of Malaysian S. aureus isolates, where hospital-associated (HA) MRSA isolates tend to carry staphylococcal cassette chromosome mec (SCCmec) type III and were of sequence type (ST)239, whereas community-associated (CA) isolates are mostly SCCmec type IV/V and ST30. More comprehensive surveillance data that include molecular epidemiological data would enable further in-depth understanding of Malaysian S. aureus isolates.

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Presence of Immune Evasion Cluster and Molecular Typing of Methicillin-Susceptible Staphylococcus aureus Isolated from Food Handlers

Journal of Food Protection ◽

10.4315/0362-028x.jfp-15-401 ◽

2016 ◽

Vol 79 (4) ◽

pp. 682-686 ◽

Cited By ~ 2

Author(s):

LÍVIA G. BAPTISTÃO ◽

NATHALIA C. C. SILVA ◽

ERIKA C. R. BONSAGLIA ◽

BRUNA F. ROSSI ◽

IVANA G. CASTILHO ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Immune Evasion ◽

Close Contact ◽

Meca Gene ◽

Low Frequency ◽

Food Handlers ◽

Spa Typing ◽

Typing Method ◽

Spa Types ◽

Immune Evasion Cluster

ABSTRACT The hands and noses of food handlers colonized by Staphylococcus aureus are an important source of food contamination in restaurants and food processing. Several virulence factors can be carried by mobile elements in strains of S. aureus, including the immune evasion cluster (IEC). This gene cluster improves the capacity of S. aureus to evade the human immune response. Many studies have reported the transmission of strains between animals and humans, such as farm workers that have close contact with livestock. However, there are few studies on the transmission between food and food handlers. The aim of this study was to detect the IEC and the mecA gene in strains isolated from food handlers and to type these strains using the spa typing method. Thirty-five strains of S. aureus isolated from the noses and hands of food handlers in three different kitchens were analyzed for the presence of the mecA gene and IEC and by spa typing. All strains were negative for the mecA gene, and the presence of IEC was observed in 10 (28.6%) strains. Fifteen different spa types were observed, with the most frequent being t127 (42.85%) and t002 (11.42%). Strains from the two most prevalent spa types and a novel spa type were typed by multilocus sequence typing. spa types t127, t002, and t13335 were determined to be multilocus sequence types (ST) ST-30, ST-5, and ST-45, respectively. The food handlers may have been contaminated by these strains of S. aureus through food, which is suggested by the low frequency of IEC and by ST that are observed more commonly in animals.

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Molecular Characterization of Plasmid-Mediated Non-O157 Verotoxigenic Escherichia coli Isolated from Infants and Children with Diarrhea

Baghdad Science Journal ◽

10.21123/bsj.2020.17.3.0710 ◽

2020 ◽

Vol 17 (3) ◽

pp. 0710

Author(s):

Md Fazlul Karim Khan ◽

Shah Samiur Rashid

Keyword(s):

Escherichia Coli ◽

Virulence Gene ◽

Multidrug Resistant ◽

Plasmid Curing ◽

Health Issues ◽

E Coli ◽

Disk Diffusion Assay ◽

Microbiological Techniques ◽

Polymerase Chain

A significant increase in the incidence of non-O157 verotoxigenic Escherichia coli (VTEC) infections have become a serious health issues, and this situation is worsening due to the dissemination of plasmid mediated multidrug-resistant microorganisms worldwide. This study aims to investigate the presence of plasmid-mediated verotoxin gene in non-O157 E. coli. Standard microbiological techniques identified a total of 137 E. coli isolates. The plasmid was detected by Perfectprep Plasmid Mini preparation kit. These isolates were subjected to disk diffusion assay, and plasmid curing with ethidium bromide treatment. The plasmid containing isolates were subjected to a polymerase chain reaction (PCR) for investigating the presence of plasmid mediated verotoxin gene (VT1 and VT2) in non-O157 E. coli. Among the 137 E. coli isolates, 49 isolates were non-O157 E. coli while 29 (59.1%) isolates were verotoxin producing non-O157 serotypes and 26 non-O157 VTEC isolates possessed plasmids. Certain isolates harboured single sized plasmid while others had multiple plasmids with different size varied from 1.8kb to 7.6kb. A plasmid containing all (100%) the isolates was multidrug-resistant. Eight isolates changed their susceptibility patterns while three isolates were found to lose plasmid after post plasmid curing treatment and the rest of the isolates (15) remained constant. Different PCR sets characterized 3 plasmid-mediated verotoxins producing non-O157 E. coli. This current study demonstrated the occurrence of plasmid mediated verotoxin gene in non-O157 E. coli. To the best of our knowledge, this is the first report in the global literature on plasmid-mediated verotoxin gene in non-O157 E. coli. Timely diagnosis and surveillance of VTEC infections should prioritize to stop or slow down the virulence gene for dissemination by plasmid-mediated gene transfer amongst the same bacteria or other species.

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Comparison of Methicillin-Resistant Staphylococcus aureus Isolates from Cellulitis and from Osteomyelitis in a Taiwan Hospital, 2016–2018

Journal of Clinical Medicine ◽

10.3390/jcm8060816 ◽

2019 ◽

Vol 8 (6) ◽

pp. 816 ◽

Cited By ~ 1

Author(s):

Kuo-Ti Peng ◽

Tsung-Yu Huang ◽

Yao-Chang Chiang ◽

Yu-Yi Hsu ◽

Fang-Yi Chuang ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Methicillin Resistant Staphylococcus Aureus ◽

Joint Infection ◽

Sccmec Type ◽

Multidrug Resistant ◽

Chang Gung Memorial Hospital ◽

Methicillin Resistant ◽

Mrsa Strains ◽

Resistance Rates

Methicillin-resistant Staphylococcus aureus (MRSA) causes superficial infections such as cellulitis or invasive infections such as osteomyelitis; however, differences in MRSA isolates from cellulitis (CL-MRSA) and from osteomyelitis (OM-MRSA) at the same local area remain largely unknown. A total of 221 MRSA isolates including 106 CL-MRSA strains and 115 OM-MRSA strains were collected at Chang-Gung Memorial Hospital in Taiwan between 2016 and 2018, and their genotypic and phenotypic characteristics were compared. We found that OM-MRSA isolates significantly exhibited higher rates of resistance to multiple antibiotics than CL-MRSA isolates. Genotypically, OM-MRSA isolates had higher proportions of the SCCmec type III, the sequence type ST239, and the spa type t037 than CL-MRSA isolates. Besides the multidrug-resistant lineage ST239-t037-SCCmecIII more prevalent in OM-MRSA, higher antibiotic resistance rates were also observed in several other prevalent lineages in OM-MRSA as compared to the same lineages in CL-MRSA. Furthermore, when prosthetic joint infection (PJI) associated and non-PJI-associated MRSA strains in osteomyelitis were compared, no significant differences were observed in antibiotic resistance rates between the two groups, albeit more diverse genotypes were found in non-PJI-associated MRSA. Our findings therefore suggest that deep infections may allow MRSA to evade antibiotic attack and facilitate the convergent evolution and selection of multidrug-resistant lineages.

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