Characterisation of Salmonella choleraesuis by PFGE and ribotypig

Salmonella (S.) Choleraesuis var. Kunzendorf is the major cause of swine salmonellosis in Poland. Eleven XbaI macrorestriction profiles and 3 ribotypes were noted amongst 36 isolates tested. Index of discrimination reached 0.88. Two clonal lineages were distinguished. One of the lines embraced the majority of 2000-2002 isolates showing over 80% genome similarity. The findings prove the clonal spread of the pathogen among swineherds in Poland

Antimicrobial resistance in non-pathogenic E. coli isolated from slaughter pigs

An increasing antimicrobial resistance in bacteria of animal origin is recognised as a public health threat. Resistant pathogens directly affect infected host and can lead to therapeutic failures whereas commensal flora may serve as a reservoir and vector of resistance genes in a populatton. The incidence of resistant non-pathogenic bacteria may also indirectly indicate the intense of antimicrobial use in animal husbandry. A five-year resistance monitoring project covering an indicator E. coli was run at the National Veterinary Research Institute since autumn 2003. The study was designed to collect yearly up to 1000 samples from healthy bovine animals, pigs, broilers, turkeys and geese at slaughter. Standard isolation and identification procedures were applied for E. coli detection in bovine and swine rectal swabs and poultry caecum contents referred to the laboratory

Antibiotic-susceptibility in Salmonella-swine isolates

Ninety-six percent of tested Salmonella swine isolates showed reduced antibiotic susceptibility. The lowest susceptibility was identified in the case of streptomycin, sulphonamides, nalidixic acid and tetracycline. The decrease in susceptibility for amoxicillin, ampicillin, enrofloxacin and chloramphenicol was observed in strains isolated during two four-year periods. Several strains developed multiresistance covering up to 9 antibiotics. Antibiotic susceptibility must be monitored to prevent therapeutic failures and spread of resistance genes in animals and humans

The potential of using E. coli as an indicator for the surveillance of antimicrobial resistance (AMR) in the environment

To understand the dynamics of antimicrobial resistance (AMR), in a One-Health perspective, surveillance play an important role. Monitoring systems already exist in the human health and livestock sectors, but there are no environmental monitoring programs. Therefore there is an urgent need to initiate environmental AMR monitoring programs nationally and globally, which will complement existing systems in different sectors. However, environmental programs should not only identify anthropogenic influences and levels of AMR, but they should also allow for identification of transmissions to and from human and animal populations. In the current review we therefore propose using antimicrobial resistant Escherichia coli as indicators for monitoring occurrence and levels of AMR in the environment, including wildlife.publishedVersio

Cross-Border Transmission of Salmonella Choleraesuis var. Kunzendorf in European Pigs and Wild Boar: Infection, Genetics, and Evolution

Salmonella enterica subspecies enterica serotype Choleraesuis is a swine adapted serovar. S. Choleraesuis variant Kunzendorf is responsible for the majority of outbreaks among pigs. S. Choleraesuis is rare in Europe, although there have been serious outbreaks in pigs including two outbreaks in Denmark in 1999–2000 and 2012–2013. Here, we elucidate the epidemiology, possible transmission routes and sources, and clonality of European S. Choleraesuis isolates including the Danish outbreak isolates. A total of 102 S. Choleraesuis isolates from different European countries and the United States, covering available isolates from the last two decades were selected for whole genome sequencing. We applied a temporally structured sequence analysis within a Bayesian framework to reconstruct a temporal and spatial phylogenetic tree. MLST type, resistance genes, plasmid replicons, and accessory genes were identified using bioinformatics tools. Fifty-eight isolates including 11 out of 12 strains from wild boars were pan-susceptible. The remaining isolates carried multiple resistance genes. Eleven different plasmid replicons in eight plasmids were determined among the isolates. Accessory genes were associated to the identified resistance genes and plasmids. The European S. Choleraesuis was estimated to have emerged in ∼1837 (95% credible interval, 1733–1983) with the mutation rate of 1.02 SNPs/genome/year. The isolates were clustered according to countries and neighbor countries. There were transmission events between strains from the United States and European countries. Wild boar and pig isolates were genetically linked suggesting cross-border transmission and transmission due to a wildlife reservoir. The phylogenetic tree shows that multiple introductions were responsible for the outbreak of 2012–2013 in Denmark, and suggests that poorly disinfected vehicles crossing the border into Denmark were potentially the source of the outbreak. Low levels of single nucleotide polymorphisms (SNPs) differences (0–4 SNPs) can be observed between clonal strains isolated from different organs of the same animal. Proper disinfection of livestock vehicles and improved quality control of livestock feed could help to prevent future spread of S. Choleraesuis or other more serious infectious diseases such as African swine fever (ASF) in the European pig production system