46 research outputs found
Cross-sectional study of hepatitis E virus (HEV) circulation in Italian pig farms
OHEJP Project: BIOPIGEE
Foodborne transmission is considered the main way of spreading zoonotic
hepatitis E virus (HEV) infection in Europe. In recent years, the human cases of
hepatitis E in subjects without history of travel in endemic areas have raised,
suggesting that domestic HEV transmission is increasing. Pork products with or
without liver, are often indicated as the source of many human foodborne HEV
cases as well as small outbreaks. Pigs are recognized as the main reservoir of
the zoonotic HEV-3 genotype, the most frequently detected in human cases in
the EU. In the absence of a harmonized surveillance of HEV circulation, data on
prevalence are heterogeneous but confirm a widespread circulation of HEV-3
in pig herds across EU. HEV-3 can pass through the food chain from farm to
fork when infected animals are slaughtered. In Italy, several studies reported the
circulation of HEV-3 in pig farms, but results are heterogeneous due to dierent
methodologies applied. In the present study, we performed a survey over 51 pig
herds belonging to three main types of farms: breeding, fattening and farrow-to-
finish. HEV-RNA was analyzed by broad range Real-time RT-PCR on 20 samples
for each farm, obtained by pooling together feces from 10 individuals. Overall,
HEV RNA was confirmed on 150 fecal pooled samples out of 1,032 (14.5%). At
least one positive pooled sample was detected from 18 farms out of 51 tested
(35.3%). By lowering the number of infected pigs at primary production, the risk
of HEV-3 entering into the food chain can be reduced. Hence, information on
HEV circulation in herds is highly relevant for choosing preventive measures and
deserves development of a monitoring program and further investigations
Investigating the cecal microbiota in broiler poultry farms and its potential relationships with animal welfare
The present study assessed the modulation of cecal microbiota and correlations with Campylobacter colonization
and animal welfare status. For these purposes, we conducted a cross sectional study of the cecal microbiota from
187 broilers reared in 13 batches from 10 poultry farms by performing 16S rRNA sequencing (regions V3–4). The
welfare of each batch was assessed using a simplified Welfare Quality® protocol, scoring higher in organic
batches, compared to both antibiotic-free and conventional batches. The bioinformatics analyses were conducted
in QIIME 2 and a linear discriminant analysis determined the association between microbiota and animals with
different Campylobacter carriage status and welfare levels. In the microbiota from the subjects negative for
Campylobacter or with high welfare scores, Bacteroidetes was the predominant phylum with the genus Megamonas
significantly increased in abundance. A greater abundance of Parabacteroides, Phascolarctobacterium, Helicobacter
in poultry negative for Campylobacter was also found at the genus level. Animals with the lowest welfare scores
showed an increased abundance of Proteobacteria. The results suggested a different microbial composition and
diversity in the analyzed groups.Italian Ministry of Health with the Ricerca Corrente 2016 funds, project IZSAM 04/16 RC (Fondo Sanitario Nazionale).https://www.elsevier.com/locate/rvscam2023Production Animal Studie
Whole genome sequence analysis of Brucella abortus isolates from various regions of South Africa
The availability of whole genome sequences in public databases permits genome-wide
comparative studies of various bacterial species. Whole genome sequence-single nucleotide polymorphisms
(WGS-SNP) analysis has been used in recent studies and allows the discrimination of
various Brucella species and strains. In the present study, 13 Brucella spp. strains from cattle of various
locations in provinces of South Africa were typed and discriminated. WGS-SNP analysis indicated a
maximum pairwise distance ranging from 4 to 77 single nucleotide polymorphisms (SNPs) between
the South African Brucella abortus virulent field strains. Moreover, it was shown that the South African
B. abortus strains grouped closely to B. abortus strains from Mozambique and Zimbabwe, as well as
other Eurasian countries, such as Portugal and India. WGS-SNP analysis of South African B. abortus
strains demonstrated that the same genotype circulated in one farm (Farm 1), whereas another farm
(Farm 2) in the same province had two different genotypes. This indicated that brucellosis in South
Africa spreads within the herd on some farms, whereas the introduction of infected animals is the
mode of transmission on other farms. Three B. abortus vaccine S19 strains isolated from tissue and
aborted material were identical, even though they originated from different herds and regions of
South Africa. This might be due to the incorrect vaccination of animals older than the recommended
age of 4–8 months or might be a problem associated with vaccine production.SUPPLEMENTARY TABLES: Table S1: Sample order used in Bruce-ladder (A) and AMOS (B) multiplex PCR assays and the descriptive information of the gel images, Table S2: Clean unique variants of the South African strains (refer to Table 2 for the sample names (in column 1) and sample ID (in column 2)).The Gauteng Department of Agriculture and Rural Development (GDARD), National Research Foundation, South Africa and Institute of Tropical Medicine, Belgium.https://www.mdpi.com/journal/microorganismsam2022Veterinary Tropical Disease
Evaluation of the House Fly Musca domestica as a Mechanical Vector for an Anthrax
Anthrax is a disease of human beings and animals caused by the encapsulated, spore-forming, Bacillus anthracis. The potential role of insects in the spread of B. anthracis to humans and domestic animals during an anthrax outbreak has been confirmed by many studies. Among insect vectors, the house fly Musca domestica is considered a potential agent for disease transmission. In this study, laboratory-bred specimens of Musca domestica were infected by feeding on anthrax-infected rabbit carcass or anthrax contaminated blood, and the presence of anthrax spores in their spots (faeces and vomitus) was microbiologically monitored. It was also evaluated if the anthrax spores were able to germinate and replicate in the gut content of insects. These results confirmed the role of insects in spreading anthrax infection. This role, although not major, given the huge size of fly populations often associated with anthrax epidemics in domestic animals, cannot be neglected from an epidemiological point of view and suggest that fly control should be considered as part of anthrax contro
Use of Canonical Single Nucleotide Polymorphism (CanSNPs) to characterize Bacillus anthracis outbreak strains in Zambia between 1990 and 2014
Anthrax caused by Bacillus anthracis is an old and neglected zoonosis that continues to raise concerns in Southern Africa. In this study, twenty (20) slides with suspected isolates of B. anthracis from anthrax cases between 1990 and 2014 and two (2) from that of a vaccine strain were analysed using MLVA with 15 VNTRs and CanSNPs test. The results from the CanSNPs indicate that all anthrax outbreaks in Zambia between 1990 and 2014 were caused by the lineage A.Br.005/006 of the clade A. This indicates a common ancestral origin of the B. anthracis circulating in the country. This data has described several environmental, wildlife, livestock and human cases that occurred in a 24 year period, from the major areas where anthrax is endemic. The molecular characterization of isolates from anthrax outbreaks in Zambia has revealed a genetic structure in agreement with previous studies from neighbouring countries. Further studies are needed to elucidate how to better manage anthrax outbreaks and define the risk maps of Zambia
Whole Genome Sequencing for Tracing Geographical Origin of Imported Cases of Human Brucellosis in Sweden
Human infections with Brucella melitensis are occasionally reported in Sweden, despite the fact that the national flocks of sheep and goats are officially free from brucellosis. The aim of our study was to analyze 103 isolates of B. melitensis collected from patients in Sweden between 1994 and 2016 and determine their putative geographic origin using whole genome sequencing (WGS)-based tools. The majority of the strains were assigned to East Mediterranean and African lineages. Both in silico Multiple Loci VNTR (Variable Number of Tandem Repeats) Analysis (MLVA) and core genome Multilocus Sequence Typing (cgMLST) analyses identified countries of the Middle East as the most probable source of origin of the majority of the strains. Isolates collected from patients with travel history to Iraq or Syria were often associated with genotypes from Turkey, as the cgMLST profiles from these countries clustered together. Sixty strains were located within a distance of 20 core genes to related genotypes from the publicly available database, and for eighteen isolates, the closest genotype was different by more than 50 loci. Our study showed that WGS based tools are effective in tracing back the geographic origin of infection of patients with unknown travel status, provided that public sequences from the location of the source are available
Characterization of Antimicrobial Resistance Patterns and Detection of Virulence Genes in Campylobacter Isolates in Italy
Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis) and detection of virulence genes (sequencing and DNA microarray analysis). The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%), tetracycline (55.86%) and nalidixic acid (55.17%). Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations