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Sequence-type 5 (ST5) of methicillin-resistant Staphylococcus aureus (MRSA), harboring the staphylococcal chromosomal cassette mec type IV (SCCmecIV), was first detected in Portugal. It emerged as a significant cause of healthcare-associated (HA) infection in pediatric units and was hence named the pediatric clone. Another ST5 lineage, which carries SCCmecII, also prevailed in the USA and Japan for multiple years. More recently, another MRSA lineage, ST105-SCCmecII, part of the evolution of clonal complex 5 (CC5) MRSA, has emerged as the cause of hospital-acquired bloodstream infection outbreaks in countries including Portugal, the USA, and Brazil. This article reviews studies on the epidemiology and evolution of these newly emerging pathogens. To this end, a search of PUBMED from inception to 2024 was performed to find articles reporting the occurrence of ST105 MRSA in epidemiologic studies. A second search was performed to find studies on MRSA, CC5, ST5, and SCCmecII. A search of PUBMED from 1999 to 2024 was also performed to identify studies on the genomics and evolution of ST5, CC5, and ST105 MRSA. Further studies were identified by analyzing the references of the previously selected articles from PUBMED. Most articles on ST105 MRSA were included in this review. Only articles written in English were included. Furthermore, only studies that used a reliable genotyping method (e.g., whole genome sequencing, or MLST) to classify the CC5 lineages were selected. The quality and selection of articles were based on the consensus assessment of the three authors in independent evaluations. In conclusion, ST105-SCCmecII is an emerging MRSA in several countries, being the second/third most important CC5 lineage, with a relatively high frequency in bloodstream infections. Of concern is the increased mortality from BSI in patients older than 15 years and the higher prevalence of ST105-SCCmecII in the blood of patients older than 60 years reported in some studies.
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Human listeriosis is an infectious disease caused by Listeria monocytogenes. The invasive form of this disease leads to a high rate of hospitalizations and fatality. The main mode of transmission is through contaminated ready-to-eat foods such as dairy, vegetables and meat products. The knowledge of the diversity and population dynamics of isolates collected from human and food sources is essential for the detection of clusters and the identification of common sites of infection. The aim of this study was the molecular characterization of L. monocytogenes isolates in Argentina. We sequenced a total of 63 isolates, 35 from human and 28 from food sources, collected between 2018 and 2023. Our genomic study divided the isolates into two lineages, four serogroups, 17 sequence types and 15 clonal complexes (CCs). The hypervirulent clone CC1 (lineage I; serogroup IVb) predominated in human and food samples. The phylogenomic analysis showed a high and possible epidemiological relationship between isolates from human and/or food sources, suggesting the presence of transmission chains in our country. These findings highlight the need to strengthen genomic surveillance of L. monocytogenes in Argentina. The identification of geographic distribution and characteristics of predominant and emerging clones from human and food sources might help to focus action plans and public health policies better directed at the control and prevention of listeriosis.
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Microbiología de Alimentos , Listeria monocytogenes , Listeriosis , Humanos , Argentina/epidemiología , Listeria monocytogenes/genética , Listeria monocytogenes/aislamiento & purificación , Listeria monocytogenes/clasificación , Listeriosis/microbiología , Listeriosis/epidemiología , FilogeniaRESUMEN
Genotyping of Staphylococcus aureus isolated from mastitis has become a fundamental tool to understand its complex epidemiology and to evaluate spillover events. The aim of this study was to describe the frequency of genotypes of the S. aureus strains isolated from intramammary infections by spa typing technique, and to evaluate the association between genotypes and the ability to form biofilm under in vitro conditions. Sixty-six strains of S. aureus recovered from bovines intramammary infections on 56 dairy herds located in 14 municipalities of the department of Antioquia were characterized. The majority of strains (65/66) were isolated from milk samples collected from dairy cows with subclinical intramammary infections. Nineteen different spa types were found in this study, t521 (19.70%), t267 (15.15%), and t605 (12.12%) being the most frequent. The strains from the t605 spa type showed the highest biofilm production. The high frequency of spa types with zoonotic potential found in this study, identified cattle as an important reservoir of theses clones for people in close proximity, such as milkers and consumers of unpasteurized dairy products.
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Enfermedades de los Bovinos , Mastitis Bovina , Infecciones Estafilocócicas , Femenino , Bovinos , Animales , Staphylococcus aureus/genética , Leche , Mastitis Bovina/epidemiología , Variación Genética , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/veterinariaRESUMEN
Fecal contamination in natural water sources is a common problem in low-income countries. Several health risks are associated with unprotected water sources, such as gastrointestinal infections caused by parasites, viruses, and bacteria. Moreover, antibiotic-resistant bacteria in water sources have become an increasing problem worldwide. This study aimed to evaluate the bacterial pathogens present in water within a rural context in Ecuador, along with the efficiency of black ceramic water filters (BCWFs) as a sustainable household water treatment. We monitored five natural water sources that were used for human consumption in the highlands of Ecuador and analyzed the total coliforms and E. coli before and after BCWF installation. The results indicated a variable bacterial contamination (29-300 colony-forming units/100mL) in all unfiltered samples, and they were considered as high risk for human consumption, but after filtration, no bacteria were present. Moreover, extended-spectrum beta-lactamase-producing E. coli with blaTEM, blaCTX-M9, and blaCTX-M1 genes, and two E. coli classified in the clonal complex ST10 (ST98) were detected in two of the locations sampled; these strains can severely impact public health. The clonal complex ST10, found in the E. coli isolates, possesses the potential to spread bacteria-resistant genes to humans and animals. The results of the use of BCWFs, however, argue for the filters' potential impact within those contexts, as the BCWFs completely removed even antibiotic-resistant contaminants from the water.
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Agua Potable , Infecciones por Escherichia coli , Escherichia coli , Filtración , Animales , Cerámica , Agua Potable/microbiología , Farmacorresistencia Bacteriana , Ecuador , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/prevención & control , Filtración/métodos , Humanos , beta-Lactamasas/genéticaRESUMEN
Polymyxin resistance is an emerging health issue aggravated by mcr dissemination among Enterobacterales recovered from various sources. Commensal Escherichia coli plays a key role in the spread of antimicrobial resistance in community settings and is likely to spread silently. It may transfer resistance genes to pathogenic bacteria in the gastrointestinal tract and the environment, and may cause difficult-to-treat infections, especially in immunocompromised patients. Unraveling actors disseminating resistance to last-resort antimicrobials might support the future development of control measures. Here we report the occurrence of a commensal ST683/CC155 colistin-resistant mcr-1.1-harboring E. coli (JP24) obtained from touristic coastal water. JP24's genome was sequenced and comparatively analyzed with other genomes from ST683/CC155 isolated worldwide and with mcr-carrying isolates recovered from various sources in Brazil. Besides mcr-1, JP24 carried blaCTX-M-8, tet(A), tet(34), dfrA12, sul2, sul3, aph(3')-Ia, aph(3')-IIa, aadA1, aadA2, cmlA1, Inu(G), mef(B) and mdf(a). mcr-1 and blaCTX-M-8 were transferable by IncX4 and IncI1/Iγ plasmids, respectively. Tree-based phylogeny of the ST683/CC155 isolates core genome revealed two larger clades. E. coli JP24 was grouped into a subclade together with an isolate from Thailand (ERR4221036), both carrying mcr-1. The core genome-based tree of the isolates carrying mcr-1 from Brazil revealed proximity with E. coli ECEST9 recovered from a mangrove also located in Northeastern Brazil. Accessory genome-based tree clustered most environmental isolates apart from the clinical ones and remained JP24 closer to ECEST9. High sequence conservation was observed between mcr-1-harboring plasmids detected in different species and reservoirs in Brazil and other countries. In addition to recreational coastal waters being potential sources for community exposure to antimicrobial-resistant bacteria, our findings reinforce a more prominent role of horizontal gene transfer, other than clonal expansion, in mcr dissemination in the community.
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Farmacorresistencia Bacteriana , Proteínas de Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Genoma Bacteriano , Brasil , Colistina/farmacología , Escherichia coli/genética , Genómica , Pruebas de Sensibilidad Microbiana , Filogenia , Agua de Mar/microbiologíaRESUMEN
Emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains in healthcare settings has changed the hospital epidemiology of MRSA in the last few years. Despite a global increase in MRSA frequency, infections caused by methicillin-susceptible S. aureus (MSSA) have persisted in healthcare settings and the community. Staphylococcus aureus isolates were collected between 2009 and 2017 at the Children's Hospital of a Caribbean city in South America. Methicillin-resistant isolates were subjected to SCCmec typing. Representative isolates were analyzed by multilocus sequence typing (MLST) and spa typing. Antibiotic susceptibility was assessed by agar dilution method. D-zone test was performed in erythromycin-resistant isolates to determine macrolide/lincosamide/streptogramin resistance. Spa typing revealed 10 different spa types. The main epidemic clones circulating during the study period were: ST8-MRSA-IVc, ST923-MRSA-IVa and ST8-MRSA-IVa. The study found high frequencies of PVL genes and resistance to erythromycin and clindamycin in the isolates. This study provides the first description of the population structure of MRSA and MSSA causing infections attended in the participating Children's Hospital. ST8-MRSA-IVc, ST923-MRSA-IVa and ST8-MRSA-IVa were the most prevalent in the isolate population.
This study was aimed to determine the distribution of sequence types, SCCmec types and antibiotic resistance profiles of MRSA and MSSA isolates recovered from pediatric patients with clinical infections attended in the Children's Hospital of a Caribbean city in South America in a period spanning 8 years. We found high frequencies of PVL genes and resistance to erythromycin and clindamycin in the isolates. The fact that MRSA and MSSA isolates in this study were frequently resistant to erythromycin and clindamycin is an indication of the selective pressure imposed by the extensive use of these two antibiotics in the treatment of skin and soft tissue infections in the geographical area of this study. This is the first study reporting the clonal distribution of Staphylococcus aureus causing infections in the pediatric population of Cartagena, a tropical city in the Caribbean coast of Colombia.
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Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Antibacterianos/farmacología , Niño , Colombia/epidemiología , Hospitales , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/genéticaRESUMEN
PURPOSE: Staphylococcus aureus is one of the main causative agents of hospital-acquired (HA) infections. In Mexico, information about the characteristics of clinical S. aureus isolates is limited. Our aim was to characterize S. aureus strains obtained from blood cultures of paediatric patients treated in a tertiary care hospital. MATERIALS AND METHODS: We analysed 249 S. aureus isolates over the period from 2006 to 2019, and their resistance profiles were determined. The isolates were classified into methicillin-resistant S. aureus (MRSA) or methicillin-sensitive S. aureus (MSSA). Staphylococcal cassettes chromosome mec (SCCmec) were detected. Virulence genes (cna, clfA, clfB, eta, etb, fnbA, fnbB, hla, pvl, sec, and tsst) were amplified, and their clonal relationships were established by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and clonal complex (CC) typing. We reviewed one hundred medical files to collect clinical information. RESULTS: Thirty-eight percent of the isolates were MRSA and showed an expanded profile of resistance to other non-beta-lactam antibiotics, while MSSA strains presented a reduced resistance profile. SCCmec-II was the most frequent element (86.3%). Eight virulence factors were detected in MSSA and six in MRSA. The pvl gene was detected in four MRSA-SCCmec-IV isolates (P≤0.0001). MRSA isolates were distributed among 14 clones and were classified into 15 sequence types (ST); the most frequent was ST1011 (17%). The most common CC in MRSA was CC5 (69%, P≤0.0001), and in MSSA, it was CC30 (30%, P≤0.0001). Eighty-seven percent of MRSA isolates were HA-MRSA, and 13% were community-acquired MRSA (CA-MRSA). Of 21 HA-MRSA isolates, 17 had SCCmec-II, while two CA-MRSA isolates had SCCmec-IV. Of MSSA isolates, 77% were derived from HA infections and 23% from CA infections. CONCLUSION: MSSA isolates had more virulence factors. MRSA isolates were resistant to more non-beta-lactam antibiotics, and those with SCCmec-IV expressed a greater variety of virulence factors. Most S. aureus isolates belonged to CC5.
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The global dissemination of multidrug-resistant Escherichia coli lineages belonging to high- risk clones poses a significant public health threat. Herein we report the identification and genomic profiling of two multidrug-resistant E. coli strains [BL-II-03(2) and BL-II-11(3)] belonging to the O15:H1-D-ST393 (clonal complex 31) worldwide spread clone, isolated from fecal samples of indigenous peoples belonging to two different ethnic groups of remote communities of Brazilian Amazon. Genomic analysis revealed genes and mutations conferring resistance to ß-lactams [blaTEM-1], aminoglycosides [aadA5, aph(3â³)-Ib, aph(6)-Id], tetracyclines [tetB], sulfamethoxazole/trimethoprim [sul1, sul2, dfrA17], and fluoroquinolones [gyrA (D87N, S83L), parC (S80I, S57T), parE (L416F)]; and presence of IncQ1, IncFIA, and IncFIB(pB171) plasmids. On the other hand, phylogenomics of globally reported E. coli ST393 assigned E. coli strains BL-II-03(2) and BL-II-11(3) to a cluster comprising human isolates from Australia, Canada, China, Sweden, and United States of America. These results might provide valuable information for understanding dissemination of intercontinental multidrug-resistant clones in remote communities with low levels of antibiotic exposure.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli/aislamiento & purificación , Fluoroquinolonas/farmacología , Escherichia coli/clasificación , Escherichia coli/genética , Heces/microbiología , Humanos , Indígenas Sudamericanos , Población RuralRESUMEN
Atopic dermatitis (AD) is a chronic inflammatory skin disease and colonization by Staphylococcus aureus may affect up to 100% of these patients. Virulent and resistant isolates can worsen AD patient clinical condition and jeopardize the treatment. We aimed to detect virulence genes and to evaluate the biofilm production of S. aureus isolates from infected skin lesions of children with AD. Methicillin resistance was detected by phenotypic and molecular tests and the virulence genes were detected by PCR. Biofilm formation was assessed by bacterial growing on microtiter plates and later stained with safranin. Genotyping was performed by Pulsed-Field Gel Electrophoresis and Multilocus Sequence Typing. Among 106 AD patients, 55 (51.8%) had developed S. aureus cutaneous infections and 23 (41.6%) were methicillin-resistant (MRSA). All 55 isolates carried the fnbA, hla, icaA, sasG, and seu genes, and more than 70% presented cna, eap, ebpS, hlg, and pvl genes. Clonal complex (CC) 30 was the main lineage found (34.5%), especially among MRSA isolates (52.2%). The egc cluster and the bbp gene were significantly the most frequent in MRSA isolates and in USA1100/ST30/CC30 lineage. Most of the isolates (74.5%) were non-biofilm producers and many of them only started to produce it in the presence of fibrinogen. There was no significant association between S. aureus isolates features and the AD severity. This study demonstrated a high frequency of CC30 MRSA isolates presenting several virulence genes in infected skin lesions of AD children in Brazil, that may influence the severity of the disease and the treatments required.
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Dermatitis Atópica/microbiología , Staphylococcus aureus Resistente a Meticilina/genética , Piel/microbiología , Factores de Virulencia/genética , Adolescente , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , Biopelículas/crecimiento & desarrollo , Brasil , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Resistencia a la Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Piel/patología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/clasificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificaciónRESUMEN
BACKGROUND: Staphylococcus aureus is a leading cause of broad-spectrum infections both in the community and within healthcare settings. Methicillin-resistant Staphylococcus aureus (MRSA) has become a global public health issue. The aim of this study was to examine the clinical and molecular characteristics of Staphylococcus aureus isolates and to define the population structure and distribution of major MRSA clones isolated in a tertiary-care hospital in Mexico. RESULTS: From April 2017 to April 2018, 191 Staphylococcus aureus isolates were collected. The frequency of MRSA was 26.7%; these strains exhibited resistance to clindamycin (84.3%), erythromycin (86.2%), levofloxacin (80.3%), and ciprofloxacin (86.3%). The majority of MRSA strains harbored the SCCmec type II (76.4%) and t895 (56.8%) and t9364 (11.7%) were the most common spa types in both hospital-associated MRSA and community-associated MRSA isolates. ST5-MRSA-II-t895 (New York /Japan clone) and ST1011-MRSA-II-t9364 (New York /Japan-Mexican Variant clone) were the most frequently identified clones. Furthermore, different lineages of Clonal Complexes 5 (85.4%) and 8 (8.3%) were predominantly identified in this study. CONCLUSION: Our study provides valuable information about the epidemiology of MRSA in a city of the central region of Mexico, and this is the first report on the association between t895 and t9364 spa types and ST5 and ST1011 lineages, respectively. These findings support the importance of permanent surveillance of MRSA aimed to detect the evolutionary changes of the endemic clones and the emergence of new strains.
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Antibacterianos/farmacología , Infecciones Comunitarias Adquiridas/microbiología , Infección Hospitalaria/microbiología , Staphylococcus aureus Resistente a Meticilina/clasificación , Tipificación Molecular/métodos , Infecciones Estafilocócicas/epidemiología , Adolescente , Adulto , Niño , Preescolar , Infecciones Comunitarias Adquiridas/epidemiología , Infección Hospitalaria/epidemiología , Farmacorresistencia Bacteriana Múltiple , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , México/epidemiología , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Filogenia , Prevalencia , Centros de Atención Terciaria , Adulto JovenRESUMEN
BACKGROUND: Ureaplasma diversum is a pathogen found in the genital tract of cattle and associated with genital disorders such as infertility, placentitis, abortion, birth of weak calves, low sperm motility, seminal vesiculitis and epididymitis. There are few studies evaluating the genetic diversity of U. diversum strains and their influence on the immune response in cattle. Therefore, to better understand genetic relationships of the pathogenicity of U. diversum, a multilocus sequence typing (MLST) scheme was performed to characterize the ATCC 49782 strain and another 40 isolates recovered from different Brazilian states. RESULTS: Primers were designed for housekeeping genes ftsH, polC, rpL22, rpoB, valS and ureA and for virulence genes, phospholipase D (pld), triacylglycerol lipase (tgl), hemolysin (hlyA), MIB-MIP system (mib,mip), MBA (mba), VsA (VsA) and ribose transporter (tABC). PCRs were performed and the targeted gene products were purified and sequenced. Sequence types (STs), and clonal complexes (CCs) were assigned and the phylogenetic relationship was also evaluated. Thus, a total of 19 STs and 4 CCs were studied. Following the molecular analysis, six isolates of U. diversum were selected, inoculated into bovine monocyte/macrophage culture and evaluated for gene expression of the cytokines TNF-α, IL-1, IL-6, IL-10 and IL-17. Differences were detected in the induction of cytokines, especially between isolates 198 and BA78, promoted inflammatory and anti-inflammatory profiles, respectively, and they also differed in virulence factors. CONCLUSION: It was observed that intra-species variability between isolates of U. diversum can induce variations of virulent determinants and, consequently, modulate the expression of the triggered immune response.
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Infecciones por Ureaplasma/veterinaria , Ureaplasma/genética , Ureaplasma/inmunología , Animales , Brasil , Bovinos , Enfermedades de los Bovinos/microbiología , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Femenino , Masculino , Tipificación de Secuencias Multilocus/veterinaria , Filogenia , Ureaplasma/clasificación , Ureaplasma/patogenicidad , Infecciones por Ureaplasma/inmunología , Virulencia/genéticaRESUMEN
Aeromonas dhakensis is an emergent human pathogen with medical importance. This study was aimed to determine the sequence types (STs), genetic diversity, and phylogenetic relationships of different clinical sources of 47 A. dhakensis from Malaysia using multilocus sequence typing (MLST), goeBURST, and phylogenetic analyses. The analysis of a concatenated six-gene tree with a nucleotide length of 2994 bp based on six housekeeping genes (gyrB, groL, gltA, metG, ppsA, and recA) and independent analyses of single gene fragments was performed. MLST was able to group 47 A. dhakensis from our collection into 36 STs in which 34 STs are novel STs. The most abundant ST521 consisted of five strains from peritoneal fluid and two strains from stools. Comparison of 62 global A. dhakensis was carried out via goeBURST; 94.4% (34/36) of the identified STs are novel and unique in Malaysia. Two STs (111 and 541) were grouped into clonal complexes among our strains and 32 STs occurred as singletons. Single-gene phylogenetic trees showed varying topologies; groL and rpoD grouped all A. dhakensis into a tight-cluster with bootstrap values of 100% and 99%, respectively. A poor phylogenetic resolution encountered in single-gene analyses was buffered by the multilocus phylogenetic tree that offered high discriminatory power (bootstrap value = 100%) in resolving all A. dhakensis from A. hydrophila and delineating the relationship among other taxa. Genetic diversity analysis showed groL as the most conserved gene and ppsA as the most variable gene. This study revealed novel STs and high genetic diversity among clinical A. dhakensis from Malaysia.
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Aeromonas/genética , Infecciones por Bacterias Gramnegativas/microbiología , Aeromonas/clasificación , Aeromonas/aislamiento & purificación , ADN Bacteriano/genética , Genes Bacterianos/genética , Genes Esenciales/genética , Variación Genética , Infecciones por Bacterias Gramnegativas/epidemiología , Humanos , Malasia/epidemiología , Filogenia , Análisis de Secuencia de ADNRESUMEN
This study aimed to characterize the main mechanisms of acquired antimicrobial resistance of 103 multidrug-resistant Acinetobacter baumannii isolated from bloodstream from 2006 to 2016 from a hospital in Londrina, Brazil. All 103 isolates were identified as A. baumannii by amplification of the blaOXA-51-like and rpoB genes. Mortality was observed in the majority (81.6%) of the patients. High non-susceptibility rates (100.0-10.7%) were obtained for the evaluated antimicrobials, including colistin, polymyxin B, and tigecycline, and most isolates were classified as extensively drug-resistant (78.6%). Carbapenemase production was observed in 92.2% of the isolates. All carbapenem-resistant isolates showed a carbapenem-hydrolyzing class D ß-lactamase being either blaOXA-23-like (97.9%) or blaOXA-143-like (2.1%). None of the isolates had the genes blaOXA-24-like, blaOXA-58-like, blaOXA-48, blaKPC, blaNDM, blaSPM-1, blaSIM-1, blaVIM, blaIMP, blaGIM, blaGES, mcr-1, qnrA, qnrB, qnrC, qnrS, and qnrVc. As a genetic context of the blaOXA-23-like gene, Tn2006 was predominated (86.0%), and Tn2008 was less frequent (12.9%). Isolates harboring the blaOXA-143-like gene showed the blaOXA-253-like variant. A polyclonal profile was observed among the A. baumannii isolates. The presence of the international clonal complexes CC113/79, CC109/1, CC110/25, and CC103/15 was detected, with prevalence of CC113/79 (38.8%). This study provides essential information to understand the antimicrobial resistance patterns of A. baumannii and can be used to strengthen infection control measures in our hospital. Also, the study reinforces the urgent need to develop stewardship programs to avoid the spread and potential outbreaks by this pathogen.
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Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Proteínas Bacterianas/genética , beta-Lactamasas/genética , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/genética , Acinetobacter baumannii/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Carbapenémicos/farmacología , Niño , Preescolar , Farmacorresistencia Bacteriana Múltiple , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Centros de Atención Terciaria , Adulto JovenRESUMEN
Bovine tuberculosis is a disease that is widely distributed around the world. Its causative agent, Mycobacterium bovis, has characteristics of a microorganism with clonal multiplication in populations with no evidence of genetic exchange between strains, and, consequently, a group of strains can be identified as descending from a common ancestor. The aim of this study was to investigate the clonal complexes of M. bovis isolated from samples of lesions suggestive of bovine tuberculosis collected from slaughterhouses in various states of Brazil between 2006 and 2012. Ninety samples were analyzed, and it was found that 14.4% belonged to the clonal complex European1 and 81.1% to the clonal complex European2, while 4.65% were not identified as any of the four known complexes.
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Mycobacterium bovis/clasificación , Mycobacterium bovis/genética , Tuberculosis Bovina/epidemiología , Animales , Brasil/epidemiología , Bovinos , Evolución Clonal/genética , Mycobacterium bovis/aislamiento & purificación , Tuberculosis Bovina/microbiologíaRESUMEN
Although Acinetobacter baumannii has become one of the most important nosocomial pathogens worldwide, very little is known about the genetic identity of isolates from less developed countries in Latin America. To alleviate this, we sequenced the genomes of 16 A. baumannii isolates from Honduras. Whole-genome sequencing was conducted on 16 isolates from five Honduran Hospitals. With the sequences of these Honduran isolates and other 42 publically available genomes, a maximum likelihood phylogeny was constructed to establish the relationship between the Honduran isolates and those belonging to the International Clones (ICs). In addition, sequence type (ST) assignation was conducted by the PubMLST, and antibiotic resistance genes were identified using ResFinder. The Honduran isolates are highly diverse and contain new allele combinations under the Bartual multilocus sequence typing scheme. The most common STs were STB447/STP10 and STB758/STP156. Furthermore, none of these isolates belongs to clonal complexes related to the ICs. Antibiotic susceptibility profiles of these isolates showed that they are multidrug resistant (MDR) or extensively drug resistant (XDR). In addition, the Honduran isolates had genes involved in resistance to seven antibiotic families. For instance, several blaOXA alleles were found, including blaOXA-23 and a gene encoding the metallo-beta-lactamase NDM-1. Notably, nine of the Honduran isolates have antibiotic resistance genes to three or more antibiotic families. In summary, in this study, we unveiled an untapped source of genetic diversity of MDR and XDR isolates; notably, these isolates did not belong to the well-known ICs.
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Infecciones por Acinetobacter/epidemiología , Acinetobacter baumannii/genética , Farmacorresistencia Bacteriana Múltiple/genética , Genes Bacterianos , Genoma Bacteriano , beta-Lactamasas/genética , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/clasificación , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/aislamiento & purificación , Antibacterianos/farmacología , Células Clonales , Monitoreo Epidemiológico , Expresión Génica , Variación Genética , Honduras/epidemiología , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Filogenia , Plásmidos/química , Plásmidos/metabolismo , Centros de Atención Terciaria , Secuenciación Completa del Genoma , beta-Lactamasas/metabolismoRESUMEN
This study examined the antimicrobial susceptibility patterns and clonal complex (CC) characteristics of serogroup 6 Streptococcus pneumoniae isolates collected from children in Beijing, China, between 1997 and 2016. Serotypes were determined using the Quellung reaction, and the antimicrobial susceptibility profiles of the isolates were determined using the disc-diffusion method or by E-test. Sequence types (STs) were assigned based on multilocus sequence typing. A total of 250 isolates were examined, with 55.2%, 30.0%, 12.8%, and 2.0% of isolates identified as serotypes 6A, 6B, 6C, and 6D, respectively. All of the isolates were susceptible to levofloxacin and vancomycin, and the non-suceptibitility rate to penicillin was 41.6%. Eighty-two distinct STs, assigned to 13 CCs and 28 singletons, were identified. CC982 was the most prevalent CC amongst serotype 6A isolates (34%), followed by CC9789 and CC3173. Amongst serotype 6B isolates, CC90 and CC4542 were the most common, accounting for 25.3% and 14.7% of isolates respectively. Over the study period, the prevalence of CC982, CC4542, and CC4536 isolates showing susceptibility to penicillin and cefuroxime decreased, and the proportion of CC3173, CC9789, CC855, and CC902 isolates showing non-susceptibility to these two antibiotics increased.(AU)
RESUMEN
ABSTRACT This study examined the antimicrobial susceptibility patterns and clonal complex (CC) characteristics of serogroup 6 Streptococcus pneumoniae isolates collected from children in Beijing, China, between 1997 and 2016. Serotypes were determined using the Quellung reaction, and the antimicrobial susceptibility profiles of the isolates were determined using the disc-diffusion method or by E-test. Sequence types (STs) were assigned based on multilocus sequence typing. A total of 250 isolates were examined, with 55.2%, 30.0%, 12.8%, and 2.0% of isolates identified as serotypes 6A, 6B, 6C, and 6D, respectively. All of the isolates were susceptible to levofloxacin and vancomycin, and the non-suceptibitility rate to penicillin was 41.6%. Eighty-two distinct STs, assigned to 13 CCs and 28 singletons, were identified. CC982 was the most prevalent CC amongst serotype 6A isolates (34%), followed by CC9789 and CC3173. Amongst serotype 6B isolates, CC90 and CC4542 were the most common, accounting for 25.3% and 14.7% of isolates respectively. Over the study period, the prevalence of CC982, CC4542, and CC4536 isolates showing susceptibility to penicillin and cefuroxime decreased, and the proportion of CC3173, CC9789, CC855, and CC902 isolates showing non-susceptibility to these two antibiotics increased.
Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/aislamiento & purificación , Streptococcus pneumoniae/efectos de los fármacos , Antibacterianos/farmacología , Penicilinas , Filogenia , Infecciones Neumocócicas/epidemiología , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/genética , Pruebas de Sensibilidad Microbiana , China , Tipificación de Secuencias Multilocus , Beijing/epidemiologíaRESUMEN
Pseudomonas aeruginosa is one of the most important pathogens worldwide. Population genetics studies have shown that the P. aeruginosa population has an epidemic structure with highly conserved clonal complexes. Nonetheless, epidemiological studies of P. aeruginosa have been historically absent or infrequent in developing countries, in which different medical treatments, conditions and infrastructure may have an impact in population dynamics and evolutionary outcomes, including antibiotic resistance profiles. In this study we contribute to fill this gap by analyzing 158 P. aeruginosa isolates from the most extensive nosocomial collection in Mexico City. We investigated the population genetic structure through a MLST approach together with a classical microbiology antibiotic resistance profiling, one of the associated concerns in the evolution of this pathogen. On the one hand, our results are in accordance with previous studies on the epidemic structure of P. aeruginosa, as well as the existence of three main phylogroups, that are not related to environmental parameters. On the other hand, antibiotic resistance profiles indicate higher prevalence in our sample of multi drug resistant (75.15%), extremely drug resistant (17.72%) and pan-drug resistant (9.49%) than resistance reported in developed countries. It is important to reflect on the causes that make less developed countries hotspots of antibiotic resistance, considering the multifactorial aspects of the socio-political context of such countries that include, but are not restricted to, public policy implementation and enforcement regarding access to antibiotics, as well as health care personnel education and other obstacles related to poverty and unequal access to health services and information.
Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Tipificación de Secuencias Multilocus , Infecciones por Pseudomonas/epidemiología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Variación Genética , Genotipo , Humanos , México/epidemiología , Epidemiología Molecular , Filogenia , Pseudomonas aeruginosa/clasificaciónRESUMEN
This study examined the antimicrobial susceptibility patterns and clonal complex (CC) characteristics of serogroup 6 Streptococcus pneumoniae isolates collected from children in Beijing, China, between 1997 and 2016. Serotypes were determined using the Quellung reaction, and the antimicrobial susceptibility profiles of the isolates were determined using the disc-diffusion method or by E-test. Sequence types (STs) were assigned based on multilocus sequence typing. A total of 250 isolates were examined, with 55.2%, 30.0%, 12.8%, and 2.0% of isolates identified as serotypes 6A, 6B, 6C, and 6D, respectively. All of the isolates were susceptible to levofloxacin and vancomycin, and the non-suceptibitility rate to penicillin was 41.6%. Eighty-two distinct STs, assigned to 13 CCs and 28 singletons, were identified. CC982 was the most prevalent CC amongst serotype 6A isolates (34%), followed by CC9789 and CC3173. Amongst serotype 6B isolates, CC90 and CC4542 were the most common, accounting for 25.3% and 14.7% of isolates respectively. Over the study period, the prevalence of CC982, CC4542, and CC4536 isolates showing susceptibility to penicillin and cefuroxime decreased, and the proportion of CC3173, CC9789, CC855, and CC902 isolates showing non-susceptibility to these two antibiotics increased.
Asunto(s)
Antibacterianos/farmacología , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificación , Beijing/epidemiología , Niño , Preescolar , China , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Penicilinas , Filogenia , Infecciones Neumocócicas/epidemiología , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/genéticaRESUMEN
ABSTRACT To characterize methicillin-resistant Staphylococcus aureus isolates from an intensive care unit of a tertiary-care teaching hospital, between 2005 and 2010. A total of 45 isolates were recovered from patients admitted to the intensive care unit in the study period. Resistance rates higher than 80% were found for clindamycin (100%), erythromycin (100%), levofloxacin (100%), azithromycin (97.7%), rifampin (88.8%), and gentamycin (86.6%). The SCCmec typing revealed that the isolates harbored the types III (66.7%), II (17.8%), IV (4.4%), and I (2.2%). Four (8.9%) isolates carried non-typeable cassettes. Most (66.7%) of the isolates were related to the Brazilian endemic clone from CC8/SCCmec III, which was prevalent (89.3%) between 2005 and 2007, while the USA100/CC5/SCCmec II lineage emerged in 2007 and was more frequent in the last few years. The study showed high rates of antimicrobial resistance among methicillin-resistant S. aureus isolates and the replacement of Brazilian clone, a well-established hospital lineage, by the USA100 in the late 2000s, at the intensive care unit under study.