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- ItemEvolution and Global Transmission of a Multidrug-Resistant, Community-Associated Methicillin-Resistant Staphylococcus aureus Lineage from the Indian Subcontinent(Washington D.C. : American Society for Microbiology, 2019) Steinig, Eike J.; Duchene, Sebastian; Robinson, D. Ashley; Monecke, Stefan; Yokoyama, Maho; Laabei, Maisem; Slickers, Peter; Andersson, Patiyan; Williamson, Deborah; Kearns, Angela; Goering, Richard V.; Dickson, Elizabeth; Ehricht, Ralf; Ip, Margaret; O'Sullivan, Matthew V.N.; Coombs, Geoffrey; Petersen, Andreas; Brennan, Gráinne I.; Shore, Anna C.; Coleman, David C.; Pantosti, Annalisa; de Lencastre, Herminia; Westh, Henrik; Kobayashi, Nobumichi; Heffernan, Helen; Strommenger, Birgit; Layer, Franziska; Weber, Stefan; Aamot, Hege Vangstein; Skakni, Leila; Peacock, Sharon J.; Sarovich, Derek; Harris, Simon; Parkhill, Julian; Massey, Ruth C.; Holden, Mathew T.G.; Bentley, Stephen; Tong, Stephen Y.C.The evolution and global transmission of antimicrobial resistance have been well documented for Gram-negative bacteria and health care-associated epidemic pathogens, often emerging from regions with heavy antimicrobial use. However, the degree to which similar processes occur with Gram-positive bacteria in the community setting is less well understood. In this study, we traced the recent origins and global spread of a multidrug-resistant, community-associated Staphylococcus aureus lineage from the Indian subcontinent, the Bengal Bay clone (ST772). We generated whole-genome sequence data of 340 isolates from 14 countries, including the first isolates from Bangladesh and India, to reconstruct the evolutionary history and genomic epidemiology of the lineage. Our data show that the clone emerged on the Indian subcontinent in the early 1960s and disseminated rapidly in the 1990s. Short-term outbreaks in community and health care settings occurred following intercontinental transmission, typically associated with travel and family contacts on the subcontinent, but ongoing endemic transmission was uncommon. Acquisition of a multidrug resistance integrated plasmid was instrumental in the emergence of a single dominant and globally disseminated clade in the early 1990s. Phenotypic data on biofilm, growth, and toxicity point to antimicrobial resistance as the driving force in the evolution of ST772. The Bengal Bay clone therefore combines the multidrug resistance of traditional health care-associated clones with the epidemiological transmission of community-associated methicillin-resistant S. aureus (MRSA). Our study demonstrates the importance of whole-genome sequencing for tracking the evolution of emerging and resistant pathogens. It provides a critical framework for ongoing surveillance of the clone on the Indian subcontinent and elsewhere.
- ItemCharacterisation of a novel composite SCCmec-SCCfus element in an emerging Staphylococcus aureus strain from the Arabian Gulf region(San Francisco : Public Library of Science, 2019) Senok, Abiola; Slickers, Peter; Hotzel, Helmut; Boswihi, Samar; Braun, Sascha D.; Gawlik, Darius; Müller, Elke; Nabi, Anju; Nassar, Rania; Nitschke, Hedda; Reißig, Annett; Ruppelt-Lorz, Antje; Mafofo, Joseph; Somili, Ali M.; Udo, Edet; Ehricht, Ralf; Monecke, StefanFusidic acid is a steroid antibiotic known since the 1960s. It is frequently used in topical preparations, i.e., ointments, for the treatment of skin and soft tissue infections caused by Staphylococcus aureus. There is an increasing number of methicillin-resistant S. aureus (MRSA) strains that harbour plasmid-borne fusB/far1 or fusC that is localised on SCC elements. In this study we examined a series of related CC30-MRSA isolates from the Arabian Gulf countries that presented with SCCmec elements and fusC, including a variant that—to the best of our knowledge—has not yet formally been described. It consisted of a class B mec complex and ccrA/B-4 genes. The fusidic acid resistance gene fusC was present, but contrary to the previously sequenced element of HDE288, it was not accompanied by tirS. This element was identified in CC30 MRSA from Kuwait, Saudi Arabia and the United Arab Emirates that usually also harbour the Panton-Valentin leukocidin (PVL) genes. It was also identified in CC8 and ST834 isolates. In addition, further CC30 MRSA strains with other SCCmec VI elements harbouring fusC were found to circulate in the Arabian Gulf region. It can be assumed that MRSA strains with SCCmec elements that include fusC have a selective advantage in both hospital and community settings warranting a review of the use of topical antibiotics and indicating the necessity of reducing over-the-counter sale of antibiotics, including fusidic acid, without prescription.Fusidic acid is a steroid antibiotic known since the 1960s. It is frequently used in topical preparations, i.e., ointments, for the treatment of skin and soft tissue infections caused by Staphylococcus aureus. There is an increasing number of methicillin-resistant S. aureus (MRSA) strains that harbour plasmid-borne fusB/far1 or fusC that is localised on SCC elements. In this study we examined a series of related CC30-MRSA isolates from the Arabian Gulf countries that presented with SCCmec elements and fusC, including a variant that—to the best of our knowledge—has not yet formally been described. It consisted of a class B mec complex and ccrA/B-4 genes. The fusidic acid resistance gene fusC was present, but contrary to the previously sequenced element of HDE288, it was not accompanied by tirS. This element was identified in CC30 MRSA from Kuwait, Saudi Arabia and the United Arab Emirates that usually also harbour the Panton-Valentin leukocidin (PVL) genes. It was also identified in CC8 and ST834 isolates. In addition, further CC30 MRSA strains with other SCCmec VI elements harbouring fusC were found to circulate in the Arabian Gulf region. It can be assumed that MRSA strains with SCCmec elements that include fusC have a selective advantage in both hospital and community settings warranting a review of the use of topical antibiotics and indicating the necessity of reducing over-the-counter sale of antibiotics, including fusidic acid, without prescription.
- ItemShared MRSA Strains among Nepalese Rhesus macaques (Macaca mulatta), their Environment and Hospitalized Patients(Lausanne : Frontiers Media, 2019) Roberts, Marilyn C.; Joshi, Prabhu Raj; Monecke, Stefan; Ehricht, Ralf; Müller, Elke; Gawlik, Darius; Paudel, Saroj; Acharya, Mahesh; Bhattarai, Sankalpa; Pokharel, Sujana; Tuladhar, Reshma; Chalise, Mukesh K.; Kyes, Randall C.This study looked at 227 saliva samples from Rhesus macaques (Macaca mulatta) and 218 samples from the surrounding environments. From these samples, MRSA isolates were collected from Rhesus saliva samples (n = 13) and environmental samples (n = 19) near temple areas in Kathmandu, Nepal. For comparison, selected MRSA isolates (n = 5) were obtained from patients with wound infections from a Kathmandu hospital. All isolates were characterized using Abbott StaphyType® DNA microarrays. Eighteen isolates (62%) from monkeys (n = 4; 31%) and environmental samples (n = 14; 74%), were CC22-MRSA-IV. Most (n = 16) of them carried both, the PVL locus and toxic shock toxin gene (tst1), an unusual combination which is the same as in previously characterized strain from Nepalese macaques and pigs. The five human isolates also belonged to that strain type. Eight monkey MRSA isolates were CC361-MRSA-IV. One MRSA from a monkey and one from an environmental sample, were CC88-MRSA-V. Other environmental MRSA included one each, CC121-MRSA-VT, and CC772 -MRSA-V. Two were CC779-MRSA-VT, potentially a novel clone. All MRSA carried the blaZ gene. The aacA–aphD, dfrA, and erm (C) genes were very common in isolates from all sources. One macaque MRSA carried the resistance genes aphA3 and sat, neither previously identified in primate MRSA isolates. This current study suggests that humans could be a potential source of the MRSA in the macaques/environment and transmission may be linked to humans feeding the primates and/or living in close proximity to each other.This study looked at 227 saliva samples from Rhesus macaques (Macaca mulatta) and 218 samples from the surrounding environments. From these samples, MRSA isolates were collected from Rhesus saliva samples (n = 13) and environmental samples (n = 19) near temple areas in Kathmandu, Nepal. For comparison, selected MRSA isolates (n = 5) were obtained from patients with wound infections from a Kathmandu hospital. All isolates were characterized using Abbott StaphyType® DNA microarrays. Eighteen isolates (62%) from monkeys (n = 4; 31%) and environmental samples (n = 14; 74%), were CC22-MRSA-IV. Most (n = 16) of them carried both, the PVL locus and toxic shock toxin gene (tst1), an unusual combination which is the same as in previously characterized strain from Nepalese macaques and pigs. The five human isolates also belonged to that strain type. Eight monkey MRSA isolates were CC361-MRSA-IV. One MRSA from a monkey and one from an environmental sample, were CC88-MRSA-V. Other environmental MRSA included one each, CC121-MRSA-VT, and CC772 -MRSA-V. Two were CC779-MRSA-VT, potentially a novel clone. All MRSA carried the blaZ gene. The aacA–aphD, dfrA, and erm (C) genes were very common in isolates from all sources. One macaque MRSA carried the resistance genes aphA3 and sat, neither previously identified in primate MRSA isolates. This current study suggests that humans could be a potential source of the MRSA in the macaques/environment and transmission may be linked to humans feeding the primates and/or living in close proximity to each other.
- ItemEmergence of novel methicillin resistant Staphylococcus aureus strains in a tertiary care facility in Tiyadh, Saudi Arabia(Macclesfield, UK : Dove Medical Press, 2019) Senok, Abiola; Somili, Ali M.; Nassar, Rania; Garaween, Ghada; Kim Sing, Garwin; Müller, Elke; Reißig, Annett; Gawlik, Darius; Ehricht, Ralf; Monecke, StefanPurpose: There is a need for continuous surveillance of methicillin-resistant Staphylococcus aureus (MRSA) to identify emergence of new strains. We hypothesize that MRSA strains are evolving with ongoing acquisition of SCCmec elements. This study was carried out to evaluate the evolution of MRSA at a tertiary care facility in Saudi Arabia. Methods: MRSA isolates associated with invasive clinical infection, which were identified in 2017 at the microbiology laboratory, King Khalid University Hospital (KKUH) in Riyadh, Saudi Arabia, were studied. The molecular characterization of isolates was carried out using StaphyType DNA microarray (Alere Technologies GmbH/Abbott, Jena, Germany). Results: The 125 MRSA isolates studied belonged to 18 clonal complexes (CC) which were distributed into 32 strain assignments. The predominant CC were CC5 (n=30), CC6 (n=17), CC80 (n=13), CC22 (n=12), CC361 (n=12). The findings demonstrated the first identification of CC152, CC361 and CC1153 MRSA as well as ST5-MRSA-[I+fus], “Geraldine Clone”, CC6-MRSA-IV (PVL+) and CC88-MRSA-V (PVL+), WA MRSA-117 in Saudi Arabia. Four novel variants were identified: CC5-MRSA-[VI+fus+tirS], CC22-MRSA-[V/VT+fus](PVL+), CC152-MRSA-[V+fus](PVL+) and CC361-MRSA-[VT+fus]. Fifty-four isolates (n/N=54/125; 43.2%) including the novel strains carried the Q6GD50 SCCfusC gene while the Panton-Valentine leukocidin genes were present in 30.4% (n/N=38/125). Conclusion: The findings demonstrate an expanding MRSA repertoire in our setting including emergence of previously unreported clonal complexes and novel strains. The high carriage of fusC gene suggests a role for fusidic acid misuse in driving the evolution of the MRSA genome and underscores the need for increased monitoring of antibiotic use.Purpose: There is a need for continuous surveillance of methicillin-resistant Staphylococcus aureus (MRSA) to identify emergence of new strains. We hypothesize that MRSA strains are evolving with ongoing acquisition of SCCmec elements. This study was carried out to evaluate the evolution of MRSA at a tertiary care facility in Saudi Arabia. Methods: MRSA isolates associated with invasive clinical infection, which were identified in 2017 at the microbiology laboratory, King Khalid University Hospital (KKUH) in Riyadh, Saudi Arabia, were studied. The molecular characterization of isolates was carried out using StaphyType DNA microarray (Alere Technologies GmbH/Abbott, Jena, Germany). Results: The 125 MRSA isolates studied belonged to 18 clonal complexes (CC) which were distributed into 32 strain assignments. The predominant CC were CC5 (n=30), CC6 (n=17), CC80 (n=13), CC22 (n=12), CC361 (n=12). The findings demonstrated the first identification of CC152, CC361 and CC1153 MRSA as well as ST5-MRSA-[I+fus], “Geraldine Clone”, CC6-MRSA-IV (PVL+) and CC88-MRSA-V (PVL+), WA MRSA-117 in Saudi Arabia. Four novel variants were identified: CC5-MRSA-[VI+fus+tirS], CC22-MRSA-[V/VT+fus](PVL+), CC152-MRSA-[V+fus](PVL+) and CC361-MRSA-[VT+fus]. Fifty-four isolates (n/N=54/125; 43.2%) including the novel strains carried the Q6GD50 SCCfusC gene while the Panton-Valentine leukocidin genes were present in 30.4% (n/N=38/125). Conclusion: The findings demonstrate an expanding MRSA repertoire in our setting including emergence of previously unreported clonal complexes and novel strains. The high carriage of fusC gene suggests a role for fusidic acid misuse in driving the evolution of the MRSA genome and underscores the need for increased monitoring of antibiotic use.
- ItemMolecular Analysis of Two Different MRSA Clones ST188 and ST3268 From Primates (Macaca spp.) in a United States Primate Center(Lausanne : Frontiers Media, 2018) Roberts, Marilyn C.; Feßler, Andrea T.; Monecke, Stefan; Ehricht, Ralf; No, David; Schwarz, StefanMethicillin-resistant Staphylococcus aureus (MRSA) were identified in macaques, their environmental facility, and nasal cultures of personnel from the Washington National Primate Research Center [WaNPRC] and included MRSA ST188 SCCmec IV and MRSA ST3268 SCCmec V. The aim of the current study was to determine the carriage of virulence genes, antibiotic resistance genes, and other characteristics of the primate MRSA isolates to determine if there were any obvious differences that would account for differences in transmission within the WaNPRC facility. In total, 1,199 samples from primates were tested for the presence of MRSA resulting in 158 MRSA-positive samples. Fifteen ST188 isolates (all from Macaca nemestrina) and nine ST3268 (four from Macaca mulatta, two from Macaca fascicularis, three from M. nemestrina), were selected for further characterization. All but one of the 15 ST188 isolates had spa type t189 and the remaining one had spa type t3887. These isolates were resistant to β-lactams [blaZ, mecA], macrolides/lincosamides [erm(B)], aminoglycosides [aacA-aphD], and fluoroquinolones. Five isolates were additionally resistant to tetracyclines [tet(K)] and had elevated MICs for benzalkonium chloride [qacC]. In comparison, the nine ST3268 isolates had the related spa types t15469 (n = 5) and t13638 (n = 4). All nine ST3268 isolates were resistant to β-lactams [blaZ, mecA], and tetracyclines [tet(K)]. Some isolates were additionally resistant to aminoglycosides [aacA-aphD], fluoroquinolones and/or showed elevated MICs for benzalkonium chloride [qacC]. In contrast to the ST188 isolates, the ST3268 isolates had the enterotoxin gene cluster egc [seg, sei, selm, seln, selo, selu] and enterotoxin genes sec and sel. The two clones have differences regarding their spa types, virulence and antibiotic resistance genes as well as ST and SCCmec types. However, the data presented does not provide insight into why ST188 spreads easily while ST3268 did not spread within the WaNPRC in-house primates.Methicillin-resistant Staphylococcus aureus (MRSA) were identified in macaques, their environmental facility, and nasal cultures of personnel from the Washington National Primate Research Center [WaNPRC] and included MRSA ST188 SCCmec IV and MRSA ST3268 SCCmec V. The aim of the current study was to determine the carriage of virulence genes, antibiotic resistance genes, and other characteristics of the primate MRSA isolates to determine if there were any obvious differences that would account for differences in transmission within the WaNPRC facility. In total, 1,199 samples from primates were tested for the presence of MRSA resulting in 158 MRSA-positive samples. Fifteen ST188 isolates (all from Macaca nemestrina) and nine ST3268 (four from Macaca mulatta, two from Macaca fascicularis, three from M. nemestrina), were selected for further characterization. All but one of the 15 ST188 isolates had spa type t189 and the remaining one had spa type t3887. These isolates were resistant to β-lactams [blaZ, mecA], macrolides/lincosamides [erm(B)], aminoglycosides [aacA-aphD], and fluoroquinolones. Five isolates were additionally resistant to tetracyclines [tet(K)] and had elevated MICs for benzalkonium chloride [qacC]. In comparison, the nine ST3268 isolates had the related spa types t15469 (n = 5) and t13638 (n = 4). All nine ST3268 isolates were resistant to β-lactams [blaZ, mecA], and tetracyclines [tet(K)]. Some isolates were additionally resistant to aminoglycosides [aacA-aphD], fluoroquinolones and/or showed elevated MICs for benzalkonium chloride [qacC]. In contrast to the ST188 isolates, the ST3268 isolates had the enterotoxin gene cluster egc [seg, sei, selm, seln, selo, selu] and enterotoxin genes sec and sel. The two clones have differences regarding their spa types, virulence and antibiotic resistance genes as well as ST and SCCmec types. However, the data presented does not provide insight into why ST188 spreads easily while ST3268 did not spread within the WaNPRC in-house primates.
- ItemClinical S. aureus Isolates Vary in Their Virulence to Promote Adaptation to the Host(Basel : MDPI, 2019) Tuchscherr, Lorena; Pöllath, Christine; Siegmund, Anke; Deinhardt-Emmer, Stefanie; Hoerr, Verena; Svensson, Carl-Magnus; Figge, Marc Thilo; Monecke, Stefan; Löffler, BettinaStaphylococcus aureus colonizes epithelial surfaces, but it can also cause severe infections. The aim of this work was to investigate whether bacterial virulence correlates with defined types of tissue infections. For this, we collected 10–12 clinical S. aureus strains each from nasal colonization, and from patients with endoprosthesis infection, hematogenous osteomyelitis, and sepsis. All strains were characterized by genotypic analysis, and by the expression of virulence factors. The host–pathogen interaction was studied through several functional assays in osteoblast cultures. Additionally, selected strains were tested in a murine sepsis/osteomyelitis model. We did not find characteristic bacterial features for the defined infection types; rather, a wide range in all strain collections regarding cytotoxicity and invasiveness was observed. Interestingly, all strains were able to persist and to form small colony variants (SCVs). However, the low-cytotoxicity strains survived in higher numbers, and were less efficiently cleared by the host than the highly cytotoxic strains. In summary, our results indicate that not only destructive, but also low-cytotoxicity strains are able to induce infections. The low-cytotoxicity strains can successfully survive, and are less efficiently cleared from the host than the highly cytotoxic strains, which represent a source for chronic infections. The understanding of this interplay/evolution between the host and the pathogen during infection, with specific attention towards low-cytotoxicity isolates, will help to optimize treatment strategies for invasive and therapy-refractory infection courses.
- ItemAnti-Staphylococcal Humoral Immune Response in patients with chronic rhinosinusitis(Amsterdam : European Rhinologic Society, 2019) Thunberg, Ulrica; Hugosson, Svante; Fredlund, Hans; Cao, Yang; Ehricht, Ralf; Monecke, Stefan; Mueller, Elke; Engelmann, Susanne; Söderquist, BoBackground: Staphylococcus aureus (S. aureus) can behave both as a harmless commensal and as a pathogen. Its significance in the pathogenesis of chronic rhinosinusitis (CRS) is not yet fully understood. This study aimed to determine serum antibody responses to specific staphylococcal antigens in patients with CRS and healthy controls, and to investigate the correlation between specific antibody response and severity of symptoms. Methodology: Serum samples from 39 patients with CRS and 56 healthy controls were analysed using a protein microarray to investigate the antibody response to S. aureus specific antigens, with a focus on immunoglobulin G (IgG) directed toward staphylococcal components accessible to the immune system. Holm-Bonferroni corrections were applied in all analyses. Information about growth of S. aureus in nares and maxillary sinus was taken from a previous study based on the same individuals. Clinical symptoms were assessed using a scoring system. Results: IgG antibody levels toward staphylococcal TSST-1 and LukF-PV were significantly higher in the CRS patient group compared to healthy controls, and levels of anti-TSST-1 antibodies were significantly higher in the CRS patient group with S. aureus in maxillary sinus than in controls. There were no correlations between the severity of symptoms and levels of serum anti-staphylococcal IgG antibody levels for LukF-PV and TSST-1. Conclusions: TSST-1 and LukF-PV could be interesting markers for future studies of the pathogenesis of CRS.