Presence of Mycobacterium bovis in slaughterhouses and risks for workers.

An investigation was carried out to detect the presence of Mycobacterium bovis in slaughterhouses where intradermal tuberculin test positive cattle were slaughtered, and to evaluate the risk of contamination by M. bovis among exposed slaughterhouse workers. Swabs were taken from the carcasses of slaughtered animals showing autoptic signs of non-generalized forms of tuberculosis, thus authorized for free consumption. Swabs were also taken from the hands and clothes of the staff employed in the butchery production line. Environmental samplings were conducted on the slaughterhouse air using filters and air aspiration devices, and on water used to wash the carcasses after slaughter. Samples from the carcasses of healthy animals were also taken on a following slaughtering session. The swabs were analysed by means of Polymerase Chain Reaction for the detection of mycobacteria. M. bovis was detected on meats, on the hands of one worker, and in the washing water. The results obtained from this study confirm that workers are highly exposed to infection by zoonotic tuberculosis, and that cleaning procedures were ineffective in our setting.

Dispersal and molecular characterisation of the Echinococcus granulosus (Batsch, 1786) complex isolated from various intermediate hosts in the Calabria region, southern Italy.

Cystic echinococcosis (CE) is a zoonotic disease caused by the tapeworms of the Echinococcus granulosus sensu lato complex, which have worldwide distribution. No data on the circulation of genotypes of the E. granulosus complex in intermediate hosts in endemic areas in Calabria are available. The aims of our study were to evaluate the dispersal of genotypes of the E. granulosus complex in Calabria and to characterise parasite isolates by Sanger sequencing and phylogenetic analysis. We collected 71 animal samples from pigs, wild boars, sheep, cattle and goats. The first PCR screening analysis targeted three partial genomic regions: the cytochrome c oxidase subunit 1 (cox1), calreticulin protein (cal) and NADH dehydrogenase subunit 1 (nad1); this identified 28 parasitic cysts. Bidirectional sequencing of cox1 amplicons and phylogenetic analysis allowed us to characterise all isolates. Molecular analyses of 28 newly generated cox1 sequences revealed that most wild boars (n = 16) and three pigs were parasitised by the larval stage of Taenia hydatidena Pallas, 1766, called cysticercus tenuicollis. Two isolates from wild boars were identified as Echinococcus canadensis Webster and Cameron, 1961 (G7), while five sheep and two goats were infected with E. granulosus G1 (sheep strain) and G1 microvariant (previously reported as G2 genotype or Tasmanian sheep strain), respectively. These molecular findings should prompt further and more extensive studies, to elucidate regional transmission patterns and to guide control programs.

Identification of pmrB mutations as putative mechanism for colistin resistance in A. baumannii strains isolated after in vivo colistin exposure.

Colistin resistance among extensively-resistant Acinetobacter baumannii isolates is a serious health-care problem. Alterations in PmrA-PmrB two-component system have been associated with resistance to colistin. We investigated three pairs of colistin-susceptible and colistin-resistant A. baumannii, sequentially isolated from three patients before and after colistin treatment, respectively. The pmrA and pmrB genes were sequenced by Sanger method. Amino acidic positions and their effect on protein were predicted by InterPro and PROVEAN tools. Expression of pmrA, pmrB and pmrC genes was assessed by semi-quantitative reverse transcription-PCR (qRT-PCR). We found three different nonsynonymous substitutions P233T, E301G and L168K in pmrB coding region, each one in a different colistin resistance strain. The E301G and L168K substitutions represent novel mutations in pmrB, not previously described. Relative expression of pmrA, pmrB and pmrC mRNA increased in all colistin resistant strains. In our study, pmrB substitutions were associated with pmrC over-expression and colistin resistance. Further studies are necessary to understand their impact on modification of lipid A components.

Prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage and pattern of antibiotic resistance among sheep farmers from Southern Italy.

PURPOSE: We conducted a cross-sectional study to measure the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization, with a particular focus on livestock associated (LA)-MRSA in farmers working in contact with livestock (sheep) in one Italian region. Furthermore, we have assessed the antimicrobial resistance pattern of isolates and the association of carriage with specific characteristic of farms and working tasks. PATIENTS AND METHODS: Demographic data, occupational history, and contact with animals information was collected. Nasal and oropharyngeal swabs were collected and all samples were tested for the isolation and identification of S. aureus. Isolates were examined for antimicrobial susceptibility and all MRSA strains underwent molecular analyses through multiple-locus variable number of tandem repeat analysis (MLVA). RESULTS: A total of 115 sheep farms and 275 sheep farmers were enrolled. MRSA colonized workers were found in three farms; S. aureus was isolated in 97 workers (35.5%), whereas MRSA was isolated in 3 (1.1%) workers. All MRSA isolates were classified as multidrug resistant. Two of the MRSA isolates were resistant to quinupristin/dalfopristin (QDA), mupirocin, erythromycin, and tetracycline. Among methicillin-susceptible S. aureus (MSSA), 32 (34%) were resistant to tetracycline, 31 (33%) to erythromycin, 26 (27.6%) to QDA, and 22 (23.4%) to linezolid and clindamycin. One MRSA belonged to MLVA complex (MC) 001, found to colonize both humans and animals. CONCLUSION: The picture of MRSA transmission among sheep farmers does not seem to be critical, although there is the need to improve adequate control measures to prevent and minimize any biological risk in sheep farms for both animal and human health. Specific monitoring/surveillance programs would help in better understanding the epidemiology of resistant strains.

Phenotypic Antimicrobial Resistance Profile of Isolates Causing Clinical Mastitis in Dairy Animals.

Mastitis is the most frequent and costly disease of lactating animals and is associated with a significant reduction in milk yield, increased cost and culling. Early and specific antibiotic based treatment reduces the severity of the disease. Over the years the extensive use of antimicrobials has led to increase antimicrobial resistance. The present study was designed to investigate the prevalence of microorganisms responsible for mastitis and their antimicrobial resistance pattern. A total of 282 milk samples were collected from different animal species (sheep, cows and goats) with clinical mastitis. Antimicrobial resistance was evaluated for Streptococcus spp. and Staphylococcus spp. In cow samples Streptococcus spp. represented the most frequently isolated genus (33.84%), while Staphylococcus spp. was the most prevalent genus in sheep and goat samples (44.4 and 73.86%, respectively). Gentamicin and chloramphenicol were found to be the most effective drugs against the tested isolates, while the highest resistance rates were observed for amoxicillin, ampicillin, tetracycline, trimethoprim-sulfamethoxazole.

Microbiological Stability of Canned Tuna Produced in Italy and in Non-European Countries.

The results of a study on the microbiological stability of canned tuna produced by Italian companies and similar canned products manufactured in countries outside Europe are reported herein. The study involved 38 samples of canned tuna of various brands, of which 14 were produced by companies outside Europe and 24 by Italian companies. Qualitative and quantitative microbiological tests were conducted for the following parameters: bacterial colony counts at 30°C, total coliforms, total Enterobacteriaceae, sulphite-reducing anaerobes, Salmonella spp., Bacillus cereus, Escherichia coli, Staphylococcus aureus, yeasts and molds. Bacterial loads and mold contamination were respectivelyin found in 8/14 (57%) samples from outside EU and 7/24 (29%) Italian samples. The bacterial flora was represented by Gram-positive bacteria (Staphylococcus warneri, Staphylococcus lentus, Streptococcus mitis, Enterococcus faecalis, Leuconostoc mesenteroides), Gram-negative bacteria (Sphingomonas paucimobilis, Acinetobacter iwoffii, Rhizobium radiobacter), spore-forming bacteria (Bacillus vallismortis), while the fungal species was represented by Penicillium spp., Rhizopus spp., Rhodotorula spp. and Alternaria spp. Excluding anomalies in the thermal treatment process of products and any contamination after treatment, the contaminations encountered in both cases were most likely due to insufficient production quality standards and the quality of the raw material used. These results may require a redefinition of the concept of commercial stability as hitherto stated.