Serotype O11 Research Articles

Microbial landscape in acute purulent-catarrhal postpartum endometritis in cows

A special place among environmental factors affecting the body of animals is occupied by microorganisms— pathogens of infectious diseases. In this regard, the problem of circulation of associations of conditionally pathogenic microorganisms capable of causing a fairly wide range of pathologies in cattle in cattle is acute. The article provides a study of the microbial background of the vaginal-luminous contents selected in the acute purulent-catarrhal postpartum endomethry in cows. It was shown that 58 strains of opportunistic microorganisms of 13 species, classified into 6 genera, were isolated from 20 cows suffering from acute purulent catarrhal endometritis. The most frequently isolated cultures were St. aureus, E. coli (serotypes O4, O9 and O83), Str. pyogenes, Str. agalactiae, P. aeruginosa, Str. uberis and Str. faecalis. Moreover, the development of acute purulent-catarrhal endometritis in cows was more often caused by grampositive bacteria. Of the 58 isolated strains of microorganisms, 22 (37.9%) cultures caused the death of white mice when administered intraperitoneally. At the same time, gram-positive cocci were more likely to have pathogenic properties, namely representatives of the genera Streptococcus spp. (11 — 50.0%) and Staphylococcus spp. (6 — 27.3%) isolates, respectively. It was found that endometritis more often causes associations of opportunistic microorganisms, which included three joints in 14 (50.0%) cases, less often four joints in 7 (25.0%) cases. The isolated microorganisms were sensitive to only three antibacterial drugs: cefkin, cefepime and marbofloxacin.

Antimicrobial resistance survey and whole-genome analysis of nosocomial P. Aeruginosa isolated from eastern Province of China in 2016–2021

BackgroundPseudomonas aeruginosa is a major Gram-negative pathogen that can exacerbate lung infections in the patients with cystic fibrosis, which can ultimately lead to death.MethodsFrom 2016 to 2021, 103 strains of P. aeruginosa were isolated from hospitals and 20 antibiotics were used for antimicrobial susceptibility determination. Using next-generation genome sequencing technology, these strains were sequenced and analyzed in terms of serotypes, ST types, and resistance genes for epidemiological investigation.ResultsThe age distribution of patients ranged from 10 days to 94 years with a median age of 69 years old. The strains were mainly isolated from sputum (72 strains, 69.9%) and blood (14 strains, 13.6%). The size of these genomes ranged from 6.2 Mb to 7.4 Mb, with a mean value of 6.5 Mb. In addition to eight antibiotics that show inherent resistance to P. aeruginosa, the sensitivity rates for colistin, amikacin, gentamicin, ceftazidime, piperacillin, piperacillin-tazobactam, ciprofloxacin, meropenem, aztreonam, imipenem, cefepime and levofloxacin were 100%, 95.15%, 86.41%, 72.82%, 71.84%, 69.90%, 55.34%, 52.43%, 50.49%, 50.49%, 49.51% and 47.57% respectively, and the carriage rate of MDR strains was 30.69% (31/101). Whole-genome analysis showed that a total of 50 ST types were identified, with ST244 (5/103) and ST1076 (4/103) having a more pronounced distribution advantage. Serotype predictions showed that O6 accounted for 29.13% (30/103), O11 for 23.30% (24/103), O2 for 18.45% (19/103), and O1 for 11.65% (12/103) of the highest proportions. Notably, we found a significantly higher proportion of ExoU in P. aeruginosa strains of serotype O11 than in other cytotoxic exoenzyme positive strains. In addition to this, a total of 47 crpP genes that mediate resistance to fluoroquinolones antibiotics were found distributed on 43 P. aeruginosa strains, and 10 new variants of CrpP were identified, named 1.33, 1.34, 1.35, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41 and 7.1.ConclusionsWe investigated the antibiotic susceptibility of clinical isolates of P. aeruginosa and genomically enriched the diversity of P. aeruginosa for its prophylactic and therapeutic value.

Outbreak of Pseudomonas aeruginosa High-Risk Clone ST309 Serotype O11 Featuring blaPER-1 and qnrVC6.

Pseudomonas aeruginosa is a leading cause of hospital-acquired infections worldwide. Biofilm production, antibiotic resistance, and a wide range of virulence factors contribute to their persistence in nosocomial environments. We describe an outbreak caused by a multidrug-resistant P. aeruginosa strain in an ICU. Antibiotic susceptibility was determined and blaPER-1 and qnrVC were amplified via PCR. Clonality was determined using PFGE and biofilm formation was studied with a static model. A combination of antibiotics was assessed on both planktonic cells and biofilms. WGS was performed on five isolates. All isolates were clonally related, resistant to ceftazidime, cefepime, amikacin, and ceftolozane-tazobactam, and harbored blaPER-1; 11/19 possessed qnrVC. Meropenem and ciprofloxacin reduced the biofilm biomass; however, the response to antibiotic combinations with rifampicin was different between planktonic cells and biofilms. WGS revealed that the isolates belonged to ST309 and serotype O11. blaPER-1 and qnrVC6 were associated with a tandem of ISCR1 as part of a complex class one integron, with aac(6')-Il and ltrA as gene cassettes. The structure was associated upstream and downstream with Tn4662 and flanked by direct repeats, suggesting its horizontal mobilization capability as a composite transposon. ST309 is considered an emerging high-risk clone that should be monitored in the Americas.

Unveiling a high-risk epidemic clone (ST 357) of ‘Difficult to Treat Extensively Drug-Resistant’ (DT-XDR) Pseudomonas aeruginosa from a burn patient in Bangladesh: A resilient beast revealing coexistence of four classes of beta lactamases

Pseudomonas aeruginosa (P. aeruginosa) stands out as a key culprit in the colonization of burn wounds, instigating grave infections of heightened severity. In this study, we have performed comparative whole genome analysis of a difficult to treat extensively drug resistant P. aeruginosa isolated from a burn patient in order to elucidate genomic diversity, molecular patterns, mechanisms and genes responsible for conferring antimicrobial resistance and virulence. P. aeruginosa SHNIBPS206 was isolated from an infected burn wound of a critically injured burn patient. Whole genome sequencing was carried out and annotated with Prokka. Sequence type, serotype, antimicrobial resistance genes and mechanisms, virulence genes, metal resistance genes and CRISPR/Cas systems were investigated. Later, pangenome analysis was carried out to find out genomic diversity. P. aeruginosa SHNIBPS206 (MLST 357, Serotype O11) was resistant to 14 antibiotics including carbapenems and harboured all four classes of beta lactamase producing genes: Class A (blaPME-1, blaVEB-9), Class B (blaNDM-1), Class C (blaPDC-11) and Class D (blaOXA-846). Mutational analysis of Porin D gave valuable insights. Several efflux pump, virulence and metal resistance genes were also detected. Pangenome analysis revealed high genomic diversity among different strains of P. aeruginosa. To our knowledge, this is the first report of an extensively drug resistant ST 357 P. aeruginosa from Bangladesh, which is an epidemic high-risk P. aeruginosa clone. Further research and in-depth comprehensive studies are required to investigate the prevalence of such high-risk clone of P. aeruginosa in Bangladesh.

Antibiotic resistance of Escherichia coli serotype O8 and O9 isolated from cattle in the Mekong Delta, Vietnam

This study was conducted to clarify the antimicrobial susceptibility and antibiotic resistance genes of Escherichia coli O8 and O9 isolated from 244 cattle feces collected from December 2021 to March 2022 in the Mekong Delta, Vietnam. E. coli was isolated from the feces following the method of TCVN 7686:2007 (ISO16654:2001), and serotypes O8 and O9 were identified by the PCR method. E. coli O8 and O9 were identified at a relatively high rate, with 15.98% and 8.20%, respectively. The disc diffusion method was applied to determine the antimicrobial susceptibility of those E. coli strains against thirteen antibiotics following the guidelines of the Clinical and Laboratory Standard Institute. Those E. coli O8 and O9 strains showed high susceptibility to amikacin (98.31%), doxycycline (96.61%), ofloxacin (94.92%), and levofloxacin (93.22%). However, those isolates exhibited resistance against ampicillin (47.46%), streptomycin (44.07%), and tetracycline (42.37%). Of those 59 E. coli strains, 35 strains (59.32%) were multiple resistant against two to twelve antibiotics with 25 resistant patterns. The pattern of Am+Ac+Co+Sm+Te+Cl was the most common type (6.78%). The prevalence of six antibiotic-resistance genes was determined by using PCR. Gene tetA was the most prevalent gene (66.10%), while cat1 was the least one (5.08%). Forty-five E. coli O8 and O9 strains (76.27%) harbored from two to four antibiotic resistance genes, and the pattern of strA+tetA+sulII was detected at the highest rate (23.73%). Therefore, the prevalence and antibiotic resistance of E. coli O8 and O9 should be controlled to protect cattle and human health.

A bittersweet fate: detection of serotype switching in Pseudomonas aeruginosa.

High-risk clone types in Pseudomonas aeruginosa are problematic global multidrug-resistant clones. However, apart from their ability to resist antimicrobial treatment, not much is known about what sets these clones apart from the multitude of other clones. In high-risk clone ST111, it has previously been shown that replacement of the native serotype biosynthetic gene cluster (O4) by a different gene cluster (O12) by horizontal gene transfer and recombination may have contributed to the global success of this clone. However, the extent to which isolates undergo this type of serotype switching has not been adequately explored in P. aeruginosa. In the present study, a bioinformatics tool has been developed and utilized to provide a first estimate of serotype switching in groups of multidrug resistant (MDR) clinical isolates. The tool detects serotype switching by analysis of core-genome phylogeny and in silico serotype. Analysis of a national survey of MDR isolates found a prevalence of 3.9 % of serotype-switched isolates in high-risk clone types ST111, ST244 and ST253. A global survey of MDR isolates was additionally analysed, and it was found that 2.3 % of isolates had undergone a serotype switch. To further understand this process, we determined the exact boundaries of the horizontally transferred serotype O12 island. We found that the size of the serotype island correlates with the clone type of the receiving isolate and additionally we found intra-clone type variations in size and boundaries. This suggests multiple serotype switch events. Moreover, we found that the housekeeping gene gyrA is co-transferred with the O12 serotype island, which prompted us to analyse this allele for all serotype O12 isolates. We found that 95 % of ST111 O12 isolates had a resistant gyrA allele and 86 % of all O12 isolates had a resistant gyrA allele. The rates of resistant gyrA alleles in isolates with other prevalent serotypes are all lower. Together, these results show that the transfer and acquisition of serotype O12 in high-risk clone ST111 has happened multiple times and may be facilitated by multiple donors, which clearly suggests a strong selection pressure for this process. However, gyrA-mediated antibiotic resistance may not be the only evolutionary driver.

Characterization of unconventional pathogenic Escherichia coli isolated from bloodstream infection: virulence beyond the opportunism.

Extraintestinal pathogenic Escherichia coli (ExPEC) is the leading cause of urinary tract infection worldwide and a critical bloodstream infection agent. There are more than 50 virulence factors (VFs) related to ExPEC pathogenesis; however, many strains isolated from extraintestinal infections are devoid of these factors. Since opportunistic infections may occur in immunocompromised patients, E. coli strains that lack recognized VFs are considered opportunist, and their virulence potential is neglected. We assessed eleven E. coli strains isolated from bloodstream infections and devoid of the most common ExPEC VFs to understand their pathogenic potential. The strains were evaluated according to their capacity to interactin vitrowith human eukaryotic cell lineages (Caco-2, T24, HEK293T, and A549 cells), produce type 1 fimbriae and biofilm in diverse media, resist to human sera, and be lethal to Galleria mellonella. One strain displaying all phenotypic traits was sequenced and evaluated. Ten strains adhered to Caco-2 (colon), eight to T24 (bladder), five to HEK-293T (kidney), and four to A549 (lung) cells. Eight strains produced type 1 fimbriae, ten adhered to abiotic surfaces, nine were serum resistant, and seven were virulent in the G. mellonella model. Six of the eleven E. coli strains displayed traits compatible with pathogens, five of which were isolated from an immune-competent host. The genome of the EC175 strain, isolated from a patient with urosepsis, reveals that the strain belonged to ST504-A, and serotype O11:H11; harbors thirteen VFs genes, including genes encoding UpaG and yersiniabactin as the only ExPEC VFs identified. Together, our results suggest that the ExPEC pathotype includes pathogens from phylogroups A and B1, which harbor VFs that remain to be uncovered.

Epidemiological investigation of Pseudomonas aeruginosa isolates including multidrug-resistant serogroup O12 isolates, by use of a rapid and simplified multiple-locus variable-number of tandem repeats analysis and whole genome sequencing

Clustered cases of Pseudomonas aeruginosa infection in immunocompromised patients' wards require rapid characterization of a potential epidemic to guide investigations and identify the potential source of contamination. To design and evaluate a rapid and simple typing method for P.aeruginosa in comparison to whole genome sequencing (WGS). A simplified polymerase chain reaction based on multiple-locus variable-number of tandem repeats analysis (MLVA) was designed and used to investigate cases of P.aeruginosa infection and colonization in a paediatric haematology department. The method was compared to WGS by using the Illumina method. On the 17 isolates recovered from 15 children (eight from blood cultures, three from urinary tract infections, one from sputum and five stool isolates), MLVA distinguished 10 different profiles, and seven isolates from six children shared the same profile. Analysis by WGS revealed that these seven isolates belonged to sequence type ST111 and serotype O12, allowing at least three different genotypes to be distinguished among them. Five environmental strains had three MLVA profiles; one was shared with a clinical isolate but WGS excluded any relationship. The simplified and inexpensive MLVA method enabled the exclusion, in less than 5h, of most of the unrelated isolates and thus to focus investigations on a small number of cases, whereas WGS, taking several days of work, drew definitive conclusions concerning the outbreak and the genetic relationships of the ST111 isolates circulating in the department. We conclude that sequential use of both methods is the optimal strategy to investigate clustered cases of P.aeruginosa infections.

The Combination of Phages and Faecal Microbiota Transplantation Can Effectively Treat Mouse Colitis Caused by Salmonella enterica Serovar Typhimurium.

Salmonella enterica serovar Typhimurium (S. Typhimurium) is one of the common causes of human colitis. In the present study, two lytic phages vB_SenS-EnJE1 and vB_SenS-EnJE6 were isolated and the therapeutic effect of the combination of phages and faecal microbiota transplantation (FMT) on S. Typhimurium-induced mouse colitis was investigated. The characteristics and genome analysis indicated that they are suitable phages for phage therapy. Results showed that vB_SenS-EnJE1 lysis 41/54 Salmonella strains of serotype O4, and vB_SenS-EnJE6 lysis 46/54 Salmonella strains of serotypes O4 and O9. Severe inflammatory symptoms and disruption of the intestinal barrier were observed in S. Typhimurium -induced colitis. Interestingly, compared with a single phage cocktail (Pc) or single FMT, the combination of Pc and FMT (PcFMT) completely removed S. Typhimurium after 72 h of treatment, and significantly improved pathological damage and restored the intestinal barrier. Furthermore, PcFMT effectively restored the intestinal microbial diversity, especially for Firmicutes/Bacteroidetes [predominantly bacterial phyla responsible for the production of short-chain fatty acids (SCFA)]. Additionally, we found that PcFMT treatment significantly increased the levels of SCFA. All these data indicated that the combination of phages and FMT possesses excellent therapeutic effects on S. Typhimurium -induced intestinal microbiota disorder diseases. Pc and FMT played roles in “eliminating pathogens” and “strengthening vital qi,” respectively. This study provides a new idea for the treatment of intestinal microbiota disorder diseases caused by specific bacterial infections.

Characterization of Uropathogenic Pseudomonas aeruginosa: Serotypes, Resistance Phenotypes, and Virulence Genotypes

Pseudomonas aeruginosa is a major cause of urinary tract infections. This organism has extended resistance to antimicrobials along with multiple virulence factors, making it difficult to treat. In this study, 49 isolates from urine samples were identified as P. aeruginosa and serotyped by the slide agglutination method. The sensitivity of isolates against 10 antipseudomonal drugs was determined. Phenotypically, lipase, protease, hemolysin, and biofilm production were detected. Genes for the type III secretion system, elastase B, and exotoxin A were detected by PCR. Serotype O11 was the most predominant serotype among test isolates. High levels of resistance were observed against ceftazidime, cefepime, piperacillin, and piperacillin/tazobactam while 10.2% of isolates were resistant to amikacin. MDR was detected in 20.4% of the isolates and was significantly associated with strong biofilm producers. About 95.9% and 63.3% of P. aeruginosa isolates had proteolytic and lipolytic activity, respectively. Among the genes detected, the exoY gene was the most prevalent gene (79.6%), while the exoU gene was the least frequent one (10.2%). toxA and lasB genes were amplified in 63.27% and 75.5% of the isolates, respectively. In addition, the exoU gene was significantly associated with MDR isolates. The high incidence of exoS, exoT, exoY, lasB, and toxA genes in uropathogenic P. aeruginosa implies that these genes can be considered markers for virulent isolates. Furthermore, the coexistence of exoU and exoS genes, even in 6% of isolates, poses a significant treatment challenge because those isolates possess both the invasive and cytotoxic properties of both effector proteins.

Draft genome sequence of a multidrug-resistant Pseudomonas aeruginosa producing blaSIM metallo-β-lactamase: London, UK

We report the draft genome sequence of a multidrug-resistant Pseudomonas aeruginosa isolate (PA3) producing SIM carbapenemase from a patient in the United Kingdom. Isolation, identification and antimicrobial susceptibility testing were performed according to local routine microbiology protocols. Whole genomic DNA was sequenced using an Illumina HiSeq platform. The generated reads were de novo assembled using SPAdes version 3.7.1. Annotation was performed by the NCBI Prokaryote Genome Annotation Pipeline version 4.6. Sequence type, antimicrobial resistance and virulence-related genes were predicted from the sequence. P. aeruginosa PA3 was resistant to most antipseudomonal β-lactams, aminoglycosides and quinolones but susceptible to colistin. The assembly comprised 100 contigs (>1000 bp) with a total length of 7 485 621 bp, and a total of 7190 coding sequences. The isolate belonged to sequence type (ST) 446, serotype O11 and contained blaSIM-1 metallo-β-lactamase in a class 1 integron structure. We report a blaSIM-1 containing multidrug-resistant strain of P. aeruginosa from the UK. Moreover, the isolate was ST 446, a genetic background with potential for greater global dissemination.

Community Fecal Carriage and Molecular Epidemiology of Extended-Spectrum β-Lactamase- and Carbapenemase-Producing Escherichia coli from Healthy Children in the Central South China.

BackgroundFecal carriage of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) and carbapenemase-producing E. coli (CP-EC) is well reported among hospitalized adults and children. However, there are few studies on the carriage prevalence and ESBL-EC and CP-EC genotypes among healthy children in China.Patients and MethodsStool samples were collected from 330 students in 2021 from three randomly selected primary schools in Changsha, China. ESBL-EC and CP-EC were screened using CHROMagarTM chromogenic plates. ESBL and carbapenemase production was confirmed using the double-disc synergy test and a modified carbapenem inactivation method, respectively. Antimicrobial susceptibility was tested using the broth microdilution method. Resistance determinants, virulence factors, and phylogenetic groups were determined by PCR and sequencing. Multi-locus sequence typing (MLST) was performed (seven housekeeping genes were amplified and sequenced) on the phylogenic group B2 E. coli to detect high-risk clonal strains such as ST131 E. coli. Then, ST131 E. coli were characterized based on ST131 clades, O-type, and fimH alleles.ResultsIn total, 118 (35.8%) ESBL-EC and 3 (0.9%) CP-EC were isolated. blaCTX-M was the most common genotype (27.1%), identified in all ESBL-EC, except one, which carried blaSHV-12. One isolate with mcr-1 was found amongst ESBL-EC, whereas all three CP-EC carried blaNDM-1. The predominant sequence type (ST) clones in group B2 were ST131 and ST1193. The prevalence of ST131 E. coli was 9.9%, displaying serotypes O16 and O25b, fimH alleles 30, 41, and 89, and ST131 clades A and C1-M27.ConclusionIn this study, high carriage rate of ESBL-EC was found among healthy children, and the dominant ESBL was CTX-M-14. In addition, high-risk clones (ST131 and ST1193) were also detected. This emphasizes the importance of monitoring ESBL-EC in community settings.

228. Epidemiology and Susceptibility Profiles of ST131-O25b Escherichia coli Detected Among Cephalosporin and/or Carbapenem-Resistant Isolates Collected in United States Hospitals

228. Epidemiology and Susceptibility Profiles of ST131-O25b <i>Escherichia coli</i> Detected Among Cephalosporin and/or Carbapenem-Resistant Isolates Collected in United States Hospitals

Global Prevalence of Yersinia enterocolitica in Cases of Gastroenteritis: A Systematic Review and Meta-Analysis.

The prevalence of Yersinia enterocolitica in gastroenteritis is often underestimated. It relates considerably to morbidity and medical expenses around the world. Understanding the cause of gastroenteritis leads to making the appropriate treatment decisions. We systematically searched PubMed, Science Direct, Embase, and Scopus to identify all published studies between Jan. 1, 2000, and Dec. 31, 2019, to assess the prevalence of Y. enterocolitica in gastroenteritis patients. A total of 5039 articles were identified that lead to the extraction of data from 47 of them. The pooled prevalence of Y. enterocolitica in cases of gastroenteritis was estimated as 1.97% (1.32–2.74%) in the culture method and 2.41% (1.07–4.22%) in the molecular method. Among the biotypes of Y. enterocolitica, 1A (62.48%) and 1B (2.14%) had the most and least prevalence, respectively. Serotype O3 Y. enterocolitica with 39.46% had the highest and O5,27 with 0.0% had the least prevalence in gastroenteritis cases. In conclusion, the findings of this systematic review show that Y. enterocolitica is prevalent in gastroenteritis in all age groups. Serotypes O3 and O9 of Y. enterocolitica had the highest prevalence and O5,27 had the least prevalence in diarrheal patients. The prevalence of Y. enterocolitica was similar in both gender and different seasons. It should be noted that to determine the role of the organism, more studies are needed especially in food-borne diseases.

Molecular characterisation of extended-spectrum \xdf-lactamase producing Escherichia coli in wild birds and cattle, Ibadan, Nigeria

BackgroundAntimicrobial resistance (AMR) is an increasing global health concern reducing options for therapy of infections and also for perioperative prophylaxis. Many Enterobacteriaceae cannot be treated anymore with third generation cephalosporins (3GC) due to the production of certain 3GC hydrolysing enzymes (extended spectrum beta-lactamases, ESBLs). The role of animals as carriers and vectors of multi-resistant bacteria in different geographical regions is poorly understood. Therefore, we investigated the occurrence and molecular characteristics of ESBL-producing Escherichia coli (E. coli) in wild birds and slaughtered cattle in Ibadan, Nigeria.Cattle faecal samples (n = 250) and wild bird pooled faecal samples (cattle egrets, Bubulcus ibis, n = 28; white-faced whistling duck, Dendrocygna viduata, n = 24) were collected and cultured on cefotaxime-eosin methylene blue agar. Antimicrobial susceptibility was determined by agar diffusion assays and all 3GC resistant isolates were genotypically characterised for AMR genes, virulence associated genes (VAGs) and serotypes using DNA microarray-based assays.ResultsAll 3GC resistant isolates were E. coli: cattle (n = 53), egrets (n = 87) and whistling duck (n = 4); cultured from 32/250 (12.8%), 26/28 (92.9%), 2/24(8.3%), cattle, egrets and whistling duck faecal samples, respectively. blaCTX-M gene family was prevalent; blaCTX-M15 (83.3%) predominated over blaCTX-M9 (11.8%). All were susceptible to carbapenems. The majority of isolates were resistant to at least one of the other tested antimicrobials; multidrug resistance was highest in the isolates recovered from egrets.The isolates harboured diverse repositories of other AMR genes (including strB and sul2), integrons (predominantly class 1) and VAGs. The isolates recovered from egrets harboured more AMR genes; eight were unique to these isolates including tetG, gepA, and floR. The prevalent VAGs included hemL and iss; while 14 (including sepA) were unique to certain animal isolates. E. coli serotypes O9:H9, O9:H30 and O9:H4 predominated. An identical phenotypic microarray profile was detected in three isolates from egrets and cattle, indicative of a clonal relationship amongst these isolates.ConclusionWild birds and cattle harbour diverse ESBL-producing E. coli populations with potential of inter-species dissemination and virulence. Recommended guidelines to balance public health and habitat conservation should be implemented with continuous surveillance.

Prevalence and risks factors associated with ESBL-producing faecal carriage in a single long-term-care facility in Spain: emergence of CTX-M-24- and CTX-M-27-producing Escherichia coli ST131-H30R.

To address the faecal carriage prevalence of antibiotic-multiresistant bacteria and associated risk factors in a public long-term care facility (LTCF). A prospective study in a single government-funded LTCF of 300 residents in Ciudad Real, Spain. Residents' clinical and demographic data were collected, as well as recent antibiotic consumption in the institution. Each participant contributed a rectal swab, which was plated on selective and differential-selective media. Colonies were identified by MALDI-TOF and ESBL production was confirmed by the double-disc synergy method, with characterization of the molecular mechanism by PCR. Isolates were typed by PFGE and submitted for ST131 screening by PCR. Faecal carriage of ESBL-producing Enterobacterales was detected in 58 (31%) of 187 participants and previous infection by MDR bacteria was identified as a risk factor. The genes characterized were: blaCTX-M-15 (40.6%); blaCTX-M-14 (28.8%); blaCTX-M-27 (13.5%); and blaCTX-M-24 (10.1%). Some 56.4% of the isolates were grouped into the E. coli ST131 clone; 70.9% of these corresponded to the O25b serotype, 51.6% of them to Clade C1 (H30) and 12.9% to Clade C2 (H30Rx). Clade C1 isolates were mostly C1-M27, whereas the C2 sublineage was mainly related to the production of CTX-M-15. ST131-CTX-M-24 isolates (n = 6) corresponded to Clade A with serotype O16. A high prevalence of ESBL-producing Enterobacterales faecal carriage has been detected in a single LTCF, highlighting the emergence of ST131 Clade A-M24 and Clade C1-M27 lineages.

Linking prescription opioids and infectious diseases

In Chicago, IL, USA, in the late 1970s, hospitalisations for infective endocarditis due to Pseudomonas aeruginosa began to increase among people who inject drugs. 1 Shekar R Rice TW Zierdt CH Kallick CA Outbreak of endocarditis caused by Pseudomonas aeruginosa serotype O11 among pentazocine and tripelennamine abusers in Chicago. J Infect Dis. 1985; 151: 203-208 Crossref PubMed Scopus (45) Google Scholar Once a rare occurrence, by 1980, P aeruginosa was the most common cause of endocarditis among people who inject drugs at Cook County Hospital (Chicago). It became clear, however, that P aeruginosa did not affect all individuals injecting drugs equally. It predominantly affected those injecting pentazocine, an opioid, and tripelennamine, an antihistamine (a combination known as T's and blues), which unlike heroin, were not boiled before injecting. 2 Botsford KB Weinstein RA Nathan CR Kabins SA Selective survival in pentazocine and tripelennamine of Pseudomonas aeruginosa serotype O11 from drug addicts. J Infect Dis. 1985; 151: 209-216 Crossref PubMed Scopus (31) Google Scholar This drug combination allowed P aeruginosa serotype O11 strains to survive, while inhibiting the growth of other P aeruginosa serotypes and Staphylococcus aureus, the latter being the main pathogen associated with infections in people using heroin. 1 Shekar R Rice TW Zierdt CH Kallick CA Outbreak of endocarditis caused by Pseudomonas aeruginosa serotype O11 among pentazocine and tripelennamine abusers in Chicago. J Infect Dis. 1985; 151: 203-208 Crossref PubMed Scopus (45) Google Scholar , 2 Botsford KB Weinstein RA Nathan CR Kabins SA Selective survival in pentazocine and tripelennamine of Pseudomonas aeruginosa serotype O11 from drug addicts. J Infect Dis. 1985; 151: 209-216 Crossref PubMed Scopus (31) Google Scholar In other words, the specific drugs and the way they were injected modulated the risk for a particular infection, with T's and blues serving as a selective medium for P aeruginosa O11. Hydromorphone and the risk of infective endocarditis among people who inject drugs: a population-based, retrospective cohort studyAmong people who inject drugs, the risk of infective endocarditis is significantly higher for those exposed to controlled-release hydromorphone than to other opioids. This association might be mediated by the controlled-release mechanism and should be the subject of further investigation. Full-Text PDF

Spread of Carbapenem Resistance by Transposition and Conjugation Among Pseudomonas aeruginosa.

The emergence of carbapenem-resistant Pseudomonas aeruginosa represents a worldwide problem. To understand the carbapenem-resistance mechanisms and their spreading among P. aeruginosa strains, whole genome sequences were determined of two extensively drug-resistant strains that are endemic in Dutch hospitals. Strain Carb01 63 is of O-antigen serotype O12 and of sequence type ST111, whilst S04 90 is a serotype O11 strain of ST446. Both strains carry a gene for metallo-β-lactamase VIM-2 flanked by two aacA29 genes encoding aminoglycoside acetyltransferases on a class 1 integron. The integron is located on the chromosome in strain Carb01 63 and on a plasmid in strain S04 90. The backbone of the 159-kb plasmid, designated pS04 90, is similar to a previously described plasmid, pND6-2, from Pseudomonas putida. Analysis of the context of the integron showed that it is present in both strains on a ∼30-kb mosaic DNA segment composed of four different transposons that can presumably act together as a novel, active, composite transposon. Apart from the presence of a 1237-bp insertion sequence element in the composite transposon on pS04 90, these transposons show > 99% sequence identity indicating that transposition between plasmid and chromosome could have occurred only very recently. The pS04 90 plasmid could be transferred by conjugation to a susceptible P. aeruginosa strain. A second class 1 integron containing a gene for a CARB-2 β-lactamase flanked by an aacA4′-8 and an aadA2 gene, encoding an aminoglycoside acetyltransferase and adenylyltransferase, respectively, was present only in strain Carb01 63. This integron is located also on a composite transposon that is inserted in an integrative and conjugative element on the chromosome. Additionally, this strain contains a frameshift mutation in the oprD gene encoding a porin involved in the transport of carbapenems across the outer membrane. Together, the results demonstrate that integron-encoded carbapenem and carbapenicillin resistance can easily be disseminated by transposition and conjugation among Pseudomonas aeruginosa strains.

Genomic Analysis of Third Generation Cephalosporin Resistant Escherichia coli from Dairy Cow Manure.

The production of extended-spectrum β-lactamases (ESBLs) conferring resistance to new derivatives of β-lactams is a major public health threat if present in pathogenic Gram-negative bacteria. The objective of this study was to characterize ceftiofur (TIO)- or cefotaxime (FOX)-resistant Escherichia coli isolated from dairy cow manure. Twenty-four manure samples were collected from four farms and incubated under anaerobic conditions for 20 weeks at 4 °C or at 25 °C. A total of 37 TIO- or FOX-resistant E. coli were isolated from two of the four farms to determine their susceptibility to 14 antibiotics. Among the 37 resistant E. coli, 10 different serotypes were identified, with O8:H1 being the predominant serotype (n = 17). Five isolates belonged to each of serotypes O9:NM and O153:H42, respectively. All 37 cephalosporin resistant isolates were multi-resistant with the most prevalent resistance spectrum being amoxicillin-clavulanic acid-ampicillin-cefoxitin-ceftiofur-ceftriaxone-chloramphenicol-streptomycin-sulfisoxazole-tetracycline-trimethoprim-sulfamethoxazole. The genomes of 18 selected isolates were then sequenced and compared to 14 selected human pathogenic E. coli reference genomes obtained from public repositories using different bioinformatics approaches. As expected, all 18 sequenced isolates carried at least one β-lactamase bla gene: TEM-1, TEM-81, CTX-M115, CTX-M15, OXA-1, or CMY-2. Several other antibiotic resistance genes (ARGs) and virulence determinants were detected in the sequenced isolates and all of them harbored antimicrobial resistance plasmids belonging to classic Inc groups. Our results confirm the presence of diverse ESBL producing E. coli isolates in dairy cow manure stored for a short period of time. Such manure might constitute a reservoir of resistance and virulence genes for other bacteria that share the same environment.

Evaluation of virulence genes in Yersinia enterocolitica strains using SYBR Green real-time PCR

Yersinia enterocolitica comprises six biotypes 1A, 1B, 2, 3, 4, and 5. The virulence of the strains belonging to biotypes 1B and 2–5 depends on the presence of both chromosomal and plasmid-borne genes. Strains belonging to biotype 1A do not carry the virulence plasmid pYV. However, they carry other virulence genes, such as ystB and hreP. The aim of this study was to investigate the distribution of yadA, virF, inv, ystA, ystB, myfA, hreP and ymoA virulence genes in Y. enterocolitica strains in order to select the target genes that could be used for the development of a probe-specific real-time PCR to determine the presence of Y. enterocolitica in food samples. A total of 161 Y. enterocolitica strains isolated in eight countries and grouped into biotypes 1A, 2 (serotypes O3, O5 and O9), 3 (serotypes O3 and O9) and 4 (serotype O3) were examined for virulence genes. The most common virulence-associated gene in pathogenic Y. enterocolitica proved to be ystA, which can therefore be considered the best target gene to be amplified in order to evaluate the presence of pathogenic biotypes. By contrast, to identify Y. enterocolitica 1A strains, ystB, which codes for the enterotoxin YstB, can be proposed. This has been found in all non-pathogenic biotypes studied, but never in pathogenic biotypes.