Background: Carbapenemase-producing Enterobacter cloacae complex (ECC) are increasingly identified in hospital-acquired infections. They usually belong to four main multilocus sequence types (STs) named ST114, ST93, ST90, and ST78. Instead, ST182 has been sporadically reported, and recently outbreaks of blaNDM-producing ST182 strains have emerged. Herein, we aimed to investigate the presence of ST182 and explore its evolution and modes of blaNDM acquisition. Methods: A phylogenetic analysis of 646 MLST STs identified among 4,685 E. hormaechei WGS assemblies deposited in public repositories was performed, as well as an in silico comparative and phylogenomic analyses for 55 WGS assemblies of ST182. blaNDM-harboring contigs were also compared to published plasmid sequences. Results: ST182 E. hormaechei strains were recovered from patients in five continents during 2011-2021. They were divided into three major genomic clusters, comprising a separate clonal complex with six other STs. In 30 out of 55 ST182 WGS assemblies, blaNDM-harboring structures were identified similar to plasmids predominant in Gram-negative bacteria, harboring resistance genes to multiple antibiotic classes and virulence genes. No associations between the genomic clusters and the country/continent of isolation, the presence and the plasmid types of the blaNDM-harboring contigs were observed. Conclusions: Our findings show that ST182 E. hormaechei strains were identified the past decade worldwide; 54.5% of them carried diverse blaNDM genetic structures, suggesting recent acquisition of the blaNDM alleles. Thus, blaNDM-producing ST182 is an emerging multidrug-resistant and virulent lineage in ECC that requires close monitoring.

Objectives Listeria monocytogenes (LM), the etiological agent of Listeriosis, can cause foodborne zoonosis. In this study, we characterized 23 strains that caused human listeriosis in Palermo (Sicily, Italy) during the period 2018-2020. In addition, we assessed the phenotypic susceptibility of clinical isolates to antibiotics in accordance with EUCAST guidelines. Methods The serogroup was determined by PCR. While MLST and MVLST were identified through the sequencing of housekeeping genes. Finally, susceptibility to antibiotics was assessed by means of the Phoenix automatic system. Results Patients hospitalized with listeriosis were predominantly males (56% vs. 44% of females). The cases were not associated with pregnancy included patients >65 years of age (60%), two of whom were affected by cancer, while cases associated with pregnancy included two pregnant women and three preterm infants. Data collected found that the main pathologies shown by patients were meningitis (60,9%) and bacteremia (39,1%). The LM strains were isolated from blood (52%), cerebrospinal fluid (26%), cerebrospinal fluid + blood (13%), blood + nasal swab (4%), and ascitic fluid (4%). The predominant serogroup was IVb (96%), whereas only one strain belonged to serogroup IIa (4%). Among the strains with serotype 4b, 4d, 4e, ST 2/VT 21 (92%) and ST6/VT19 (4%) were determined, while only isolates with serotype 1/2a, 3a show ST155/VT45 (CC155). Conclusion This study revealed the widespread circulation of a single clinical strain (ST2/VT21) associated with suspected food contamination, demonstrating the importance of carrying out molecular epidemiological surveillance. Our clinical isolates were susceptible to the assayed beta-lactams, in agreement with the literature data.

Control and eradication of brucellosis is an objective for Veterinary and Health Authorities in several countries worldwide. Efficient surveillance programs are crucial for detecting and managing outbreaks, and epidemiological investigations may take advantage from the presence of standardized and efficient molecular typing techniques and analytical tools that enable public health laboratories to identify the origin of an outbreak. The aim of this study was to sequence Brucella spp. strains isolated in Iraq from different ruminant species, to verify whether there was a spatial or temporal clustering and, above all, shedding light on how these Iraqi isolates are positioned in the phylogenetic context of Brucella spp. The isolates under study (N=35) were from abortion, milk, placenta and fetal membrane of sheep, cattle and buffalo. Samples were genotyped using different techniques, namely MLVA-16, Whole Genome Sequencing, MLST and cgMLST. The findings of this study suggests that even relatively small investigations can provide sufficient evidence to justify improvements in existing control strategies. The application of different control measures in different territories, based on molecular epidemiological studies, would increase the chances to maximize public health benefits and minimize the spread of infection to areas free from the disease or with lower prevalence.

Klebsiella pneumoniae (Kp) has gained prominence in the last two decades due to its global spread as a multi-drug resistant (MDR) pathogen. Further, Carbapenem-Resistant Kp are emerging at an alarming rate. The objective of this study was (1) to evaluate the prevalence of β-lactamases, especially carbapenemases in Kp isolates from India, (2) determine the most prevalent sequence type (ST) & plasmids, and their association with β-lactamases. Clinical samples of K. pneumoniae (n=65) were collected from various pathology lab, drug susceptibility and minimum inhibitory concentrations (MIC) were detected. Whole genome sequencing (WGS) was done for (n=22) resistant isolates and WGS analysis was performed using various bioinformatics tools. Additional Indian MDR Kp genomes (n=187) were retrieved using Pathosystems Resource Integration Center (PATRIC) database. Detection of β-lactamase genes, location, plasmid replicons, and ST type of genomes were carried out using CARD, mlplasmids, PlasmidFinder, and PubMLST respectively. All data were analyzed and summarized using iTOL tool. ST231 was highest, followed by ST147, ST2096 & ST14 among Indian isolates. blaAmpH was detected as the most prevalent gene followed by blaCTX-M-15, blaTEM-1. Among carbapenemase genes, blaOXA-232 was prevalent and associated with ST231, ST2096 and ST14, which was followed by blaNDM-5 which was observed to prevalent in ST147, ST395 &ST437. ST231 genomes were most commonly found to carry Col440I and ColKP3 plasmids. ST16 carried mainly ColKP3, and Col (BS512) was abundantly present in ST147 genomes. One Kp isolate with novel MLST profile was identified, which carried blaCTX-M-15, blaOXA-1 and blaTEM-1. ST16 &ST14 from this study, which is mostly dual producer of carbapenem and ESBL genes, could be emerging high-risk clones in India.

We investigated the prevalence and genetic diversity of Wolbachia pipientis strains in Aedes albopictus populations in Greece. Using a combination of PCR and Sanger sequencing techniques, we genotyped Wolbachia strains in 105 mosquitoes collected across eight different prefectures in 2021. We found a high prevalence of Wolbachia in both male (90%) and female (97%) mosquitoes. Among the infected samples, 84% had double infections with both wAlbA and wAlbB strains, while 16% had infections with only wAlbB. Our comparison of the Multi-Locus Sequence Typing (MLST) profile, employing gatB-coxA-hcpA-ftsZ-fbpA genotyping, revealed a single MLST profile for each wAlbA and wAlbB strain in Greek populations. The same MLST profiles were also reported in populations from China, Russia, and Argentina, suggesting low levels of global diversity in wAlbA and wAlbB strains. Furthermore, our results indicated a significant association between temperature and the prevalence of single infections (P = 6.498E-07), with higher temperatures correlating with an increased likelihood of single infections. Although male-bias showed a tendency towards single infections, the effect was marginally non-significant (P = 0.053). These results were confirmed using a bootstrap-with-replacement analysis approach. Overall, our findings offer novel insights into the distribution and species diversity of Wolbachia strains in Greek Ae. albopictus populations, emphasizing the importance of understanding the short-term plastic and adaptive responses of these organisms to environmental stressors and rapid climate change.

Rickettsia is an important pathogenic entity among tick-borne diseases (TBD), which are considered serious emerging public health problems globally. In India, though the widespread distribution of ticks and TBD has been documented, its real burden remains underreported. In a preliminary attempt, rickettsial surveillance was carried out in ticks collected from Sirumalai, Eastern Ghats in Tamil Nadu by using pathogen genome-based phylogenetic inferences generated through multi-locus sequence typing (MLST), targeting the genes 16s rRNA, OmpA, OmpB, and gltA by nested PCR. The laboratory evidence confirms the circulation of Rickettsia in Haemaphysalis intermedia species collected from this area. Analysis of the four gene sequences detected demonstrates their closest identity to the spotted fever group (SFG) available in the GenBank database. Further, multiple sequence alignment with other sequences derived from the GenBank database showed close relatedness to Rickettsia conorii subsp. raoultii (16s rDNA-99.32%, ompA-93.38%, ompB-97.39%, and gltA-98.57%) and Rickettsia felis (ompA-100%, ompB-100% and gltA-99.41%). With this genomic evidence, the circulation of rickettsial pathogens in the pools of H. intermedia ticks infesting livestock in the Sirumalai foothill area has been demonstrated and to complement the microscopic identification of the tick species, DNA barcodes were generated for H. intermedia using the mitochondrial cytochrome c oxidase subunit I gene (COI). Nevertheless, R. raoultii and R. felis were found to be the aetiological agents of tick-borne lymphadenopathy and flea-borne spotted fever in human cases, respectively. Further study on the determination of their diversity, distribution, clinical relevance, and potential risk to the local community in these areas is highly warranted.

Escherichia coli is an indicator microorganism in One Health antibiotic resistance surveillance programmes. The purpose of the study was to describe and compare E. coli isolates obtained from pigs and human contacts from a commercial farm in South Africa using conventional methods and whole genome sequencing (WGS). Porcine E. coli isolates were proportionally more resistant phenotypically and harboured a richer diversity of antibiotic resistance genes, as compared to human E. coli isolates. Different pathovars, namely ExPEC (12.43%, 21/169), ETEC (4.14%; 7/169), EPEC (2.96%, 5/169), EAEC (2.96%, 5/169) and STEC (1.18%, 2/169) were detected at low frequencies. Sequence type complex (STc) 10 were the most prevalent (85.51%, 59/169) among human and porcine isolates. Six STcs (STc10, STc86, STc168, STc206, STc278 and STc469) were shared at the human-livestock interface according to multilocus sequence typing (MLST). Core genome MLST and hierarchical clustering (HC) showed that human and porcine isolates were overall genetically diverse, but some clustering at HC2 to HC200 were observed. In conclusion, even though the isolates shared a spatio-temporal relationship, there were still differences in the virulence potential, antibiotic resistance profiles, and cgMLST and HC according to the source of isolation.