Enteropathogenic Escherichia coli (EPEC) is one of the main pathotypes causing gastroenteritis, particularly in young immunocompromised hosts. The study reports the prevalence, characterisation, and molecular epidemiology of EPEC from piglets in northeastern India. A total of 457 faecal samples were collected, from which 1,286 E. coli strains were isolated and screened by PCR. The resultant EPEC strains were serotyped and phenotypically characterised for resistance against 15 antimicrobials. Also, the phylogenetic sequence was analysed for 11 selected strains. A total of 42 strains (3.26%) belonged to atypical EPEC, of which, 15 (35.71%, and 2.29% of the 654 strains from this farm type) were isolated from organised and 27 (64.29%, and 4.27% of the 632 strains from this farm type) from unorganised farms; further, 5 (11.90% of the EPEC strains and 1.51% of the 330 strains from this breed) were isolated from the indigenous breeds and 37 (88.10%, and 3.87% of the 956 strains from this breed) from crossbred piglets. Serogroups O111 (11.9%) and O118 (7.14%) were the most prevalent of the 10 present. Sequence analysis of a length of the eaeA gene of 11 isolates of the region showed them to have 100% homology with each other and their identity ranged from 99.4% to 99.7% with GenBank reference sequences. All the EPEC isolates were multi-drug resistant, showing the highest resistance to amoxicillin (80.9%) and cephalexin (76.19%). The study highlighted the association of EPEC with piglet’s diarrhoea in northeastern India. EPEC isolates belonged to many serotypes and phenotypically all were multi-drug resistant with close genetic homology.

Yersiniosis is a zoonosis causing gastroenteritis, diarrhoea, and occasionally reactive arthritis and septicaemia. Cases are often linked to meat consumption and the most common aetiological agent is the Gram-negative bacilliform Yersinia enterocolitica bacterium. The occurrence of Yersinia spp. among wild animals has mostly been studied in wild boar, but it has seldom been in other species. A total of 1,868 faecal samples from animals found dead or hunted were collected between 2015 and 2018 in the Valle d’Aosta region of the northwestern Italian Alps. Alpine ibex faecal samples were collected during a health monitoring program in 2018. Bacteria were isolated via PCR and confirmed as Y. enterocolitica biochemically. Strain antimicrobial susceptibility was tested by Kirby–Bauer disc diffusion, and the presence of virulence factors and antimicrobial resistance genes was investigated using whole-genome sequencing. Yersinia enterocolitica strains of biotype 1A were detected in six faecal samples from red deer (0.93%), roe deer (0.49%) and red foxes (0.7%). Strains found in beech martens (3.57%) and Alpine ibex (2.77%) belonged to biotypes 1B and 5, respectively and harboured the pYPTS01 plasmid that had only been detected in Y. pseudotuberculosis PB1/+. All the isolates were resistant to ampicillin and erythromycin. The biovar 1A strains exhibited different virulence factors and behaved like non-pathogenic commensals. The strain from an Alpine ibex also harboured the self-transmissible pYE854 plasmid that can mobilise itself and the pYPTS01 plasmid to other strains. The beech marten could be considered a sentinel animal for Y. enterocolitica. Phenotypic resistance may account for the ability of all the strains to resist β-lactams.

It has been suggested that coagulase-negative staphylococci can serve as reservoirs of virulence genes for other bacteria. This study assessed the presence of such genes in selected isolates recovered from meat of the giant African snail (Achatina achatina). Virulence genes were detected using a polymerase chain reaction targeting specific primers. Two representative isolates were identified using 16S rRNA gene sequencing. The results showed that the staphylococcal enterotoxin A gene (sea) was present in five out of the eight isolates studied. The isolates expressed resistance mainly to three antibiotics: chloramphenicol, norfloxacin and cloxacillin in descending order of incidence. Most importantly, the Staphylococcus sciuri isolate NEDU 181, in addition to being resistant to the three aforementioned antibiotics, also harboured the sea gene. Our findings demonstrate, for the first time, the presence of toxigenic and antibiotic-resistant coagulase-negative Staphylococcus spp. in commercially-available fresh snail meat. With staphylococcal enterotoxin A known to survive cooking temperature, this presents a food safety concern.

Contamination by Staphylococcus aureus of food produced from animal sources may have diverse and multifactorial causes that depend on geographical distribution. The goal of this study was to isolate and characterise S. aureus strains from contaminated fermented pork sausage, which is a local food of northeastern Thailand. S. aureus strains were isolated from local pork sausage, and the presence of classical enterotoxins was determined by PCR and reversed passive latex agglutination. These results were compared with strains derived from hospitalised patients and healthy carriers. Additionally, production of extracellular enzymes and haemolysin, biofilm formation, and antibiotic susceptibility were assessed. S. aureus was identified in 36 sausage isolates (60%). The strains positive for staphylococcal enterotoxin A were more frequently found in isolates from sausage and healthy carriers than in those from patients. All tested S. aureus strains were positive for DNase, lipase, proteinase, haemolysin, and biofilm formation; notably, strains isolated from food and healthy carriers displayed similar values. Most isolates were resistant to penicillin and ampicillin, while none were to methicillin. Thai fermented pork sausages are associated with a high risk of staphylococcal food poisoning, which may be linked to contamination caused by carriers. Dissemination of knowledge regarding best practices in sanitation and hygiene is important in local communities.

The Shewanella putrefaciens group are ubiquitous microorganisms recently isolated from different freshwater fish species and causing serious health disorders. The purpose of the study was to characterise isolates of the S. putrefaciens group with special emphasis on elucidating serological diversity and determining putative virulence factors. Isolates collected from freshwater fish (n = 44) and reference strains were used. The identification of bacteria was carried out using biochemical kits and 16S rRNA sequencing. Polyclonal antibodies were prepared against the S. putrefaciens group. The bacterium’s susceptibility to antimicrobial agents, its enzymatic properties, and its adhesion ability to fish cell lines were also tested. Finally, selected isolates were used in challenge experiments in common carp and rainbow trout. Excluding six isolates undeterminable for species, the bacteria were classified to three species: S. putrefaciens, S. xiamenensis, and S. oneidensis, and showed some phenotypic diversity. Fourteen serological variants of the S. putrefaciens group were determined with the newly developed serotyping scheme. Serodiversity may play an important role in the virulence of particular isolates. Further, S. putrefaciens group members adhere to epithelial cells and produce enzymes which may contribute to their virulence. Challenge tests confirmed the pathogenicity of the S. putrefaciens group for fish.

Avian pathogenicEscherichia coli (APEC) causes serious colibacillosis and significant economic losses. Data on profiles of virulence factors and antibiotic resistances among APEC strains are crucial to the control of infection. In this study, strains were isolated from eastern China, and the prevalence of virulence factors and distribution of antibiotic resistance were determined. APEC strains were isolated and characterised by PCR for O serogroups, virulence factor genes, antibiotic resistance, and phylogenetic groups. O78 was the most prevalent serogroup and type A was the most frequent phylogenetic group. ThefimH,feoB, andiron genes were the most prevalent among the isolates. All isolates were multiresistant, and all strains were resistant to ampicillin and tetracycline, which are widely used in the poultry industry in China. This study provided important data on the presence of virulence genes and antibiotic resistance profiles of APEC from poultry farms in eastern China.

Changes occurring in freshwater ecosystems seem to be fundamental in the development of all microorganisms, including those pathogenic to fish. This has been especially evident in recent years during which dynamic variations in bacterial fish pathology have been observed. Gram-negative bacteria commonly known to be pathogenic to fish, like Aeromonas spp., Flavobacterium spp., Pseudomonas spp., and Shewanella putrefaciens are replaced by other species, which until now have not been known to be virulent or even conditionally pathogenic to fish. Nowadays, among these other species Acinetobacter spp., Plesiomonas shigelloides, Sphingomonas paucimobilis, and Stenotrophomonas maltophilia are the most frequently isolated from fish exhibiting clinical signs of disease. Two Gram-positive bacteria have become pathogens of particular importance in fish pathology in Poland: Lactococcus garviae and Streptococcus iniae. In addition, infections caused by the Gram-positive bacterium Kocuria rhizophila have appeared in recent years. This bacterium has not been known until now to be pathogenic to fish. Therefore, this infection could be called an emergent disease.

Introduction: Colibacillosis – the most common disease of poultry, is caused mainly by avian pathogenic Escherichia coli (APEC). However, thus far, no pattern to the molecular basis of the pathogenicity of these bacteria has been established beyond dispute. In this study, genomes of APEC were investigated to ascribe importance and explore the distribution of 16 genes recognised as their virulence factors. Material and Methods: A total of 14 pathogenic for poultry E. coli strains were isolated, and their DNA was sequenced, assembled de novo, and annotated. Amino acid sequences from these bacteria and an additional 16 freely available APEC amino acid sequences were analysed with the DIFFIND tool to define their virulence factors. Results: The DIFFIND tool enabled quick, reliable, and convenient assessment of the differences between compared amino acid sequences from bacterial genomes. The presence of 16 protein sequences indicated as pathogenicity factors in poultry resulted in the generation of a heatmap which categorises genomes in terms of the existence and similarity of the analysed protein sequences. Conclusion: The proposed method of detection of virulence factors using the capabilities of the DIFFIND tool may be useful in the analysis of similarities of E. coli and other sequences deriving from bacteria. Phylogenetic analysis resulted in reliable segregation of 30 APEC strains into five main clusters containing various virulence associated genes (VAGs).

Akabane virus (AKAV) has been detected in a variety of host species in China, but there are only limited records of its occurrence in goats. However, more attention needs to be paid to understanding the diversity of viruses in this species. The aim of the study was to explore the genotype characteristics and variation trend of AKAV and their relationship with virulence in Yunnan, China. Blood samples were collected from goats during routine surveillance of goat diseases in Yunnan province in 2019. The AKAV CX-01 strain was isolated using BHK-21 cells. To understand pathogenicity, the virus was intraperitoneally (IP) and intracerebrally (IC) inoculated into suckling mice and tissue samples were subsequently analysed histopathologically and immunohistochemically. Akabane virus CX-01 strain induced encephalitis and impairment of the central nervous system with fatal consequences. Phylogenetic analysis based on the ORF sequences of the small segments indicated that the AKAV isolate used was most closely related to the GD18134/2018 Chinese midge and bovine NM BS/1strains, while phylogenetic analysis based on the medium segments showed a close relationship between CX-01 and the Chinese GLXCH01 strain. The CX-01 isolate was related to AKAV genogroup Ia and probably originated from a recombination of different strains.

The objective of this study was to determine the prevalence and characteristics of antimicrobial-resistant Enterococcus faecalis and E. faecium isolated from the oral cavities of captive giant pandas in China. The virulence-associated determinant and antimicrobial resistance genes were detected and antimicrobial susceptibility tests were performed on 54 strains of each bacterium. All isolates showed 100% multidrug resistance. E. faecalis isolates showed a higher percentage of strains resistant to gentamicin (48.1%), vancomycin (55.6%), linezolid (100%), and streptomycin (33.3%) than E. faecium isolates. The resistance genes of Enterococcus spp. were present to highly varying extents according to antibiotic type, their presence breaking down for E. faecalis and E. faecium respectively as aac(6')/aph(2″) 5.56% and 5.56%; aph(3')-Ⅲ 0% and 14.81%; ant(6)-I 0% and 3.7%; ant(4')-Ia 0% and 64.81%; tetL 20.37% and 100%; vanA 92.59% and 46.3%; vanB 0% and 0%; cfr 0% and 90.74%; optrA 96.3% and 3.7%; blaZ 0% and 1.85%; blaTEM 0% and 0%; tetA 20.37% and 0%; tetC 24.07% and 100%; tetM 0% and 0%; ermA 12.96% and 100%; ermB 5.56% and 3.7%; and ermC 0% and 1.85%.Virulence-associated determinants were detected in this research, which typically include efaA, gelE, asa1, ace, cylA, esp and hyl; however, the latter three were not detected. High proportions of the isolates carried the efaA, gelE, asa1, and ace genes. Respectively for E. faecalis and E. faecium their detection was efaA 98.1% and 85.2%; gelE 98.1% and 87%; asa1 92.6% and 87%; and ace 87% and 85.2%. This is the first study on the potential disease risk and antimicrobial-resistant characteristics of E. faecalis and E. faecium isolates in giant panda oral cavities. The results of this study show that the antimicrobial resistance rate of Enterococcus spp. isolated from the oral cavity of captive pandas is very high, and thus needs to be monitored.