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AIMS: To provide an epidemiologic interpretation of a suspected outbreak of food poisoning caused by Salmonella enterica subspecies enterica serovar Berta strains isolated from humans and from the leftovers of the implicated foods (cream, dairy-based desserts and eggs). METHODS AND RESULTS: We have correlated the similarity between the strains through genotyping with Pulsed Field Gel Electrophoresis (PFGE), studying antimicrobial sensitivity patterns and epidemiological investigation. The clonal origin of the outbreak was confirmed by all laboratory tests. PFGE analysis of the restriction profiles obtained with XbaI and SpeI revealed a certainly correlation from the strains isolated from the various sources, while the antimicrobial sensitivity pattern was the same in all cases, with all strains sensitive to all antibiotics tested. CONCLUSIONS: Poor hygiene conditions in the facility concerned, lack of hygiene in food handling, high summer temperatures and positive cultures from asymptomatic staff could all be implicated in the infection, with food being the means through which it spread. SIGNIFICANCE AND IMPACT OF THE STUDY: This study describes the first outbreak of food poisoning caused by Salmonella enterica subspecies enterica serovar Berta (Salmonella Berta) reported in Italy. It confirms the importance of correlating epidemiological investigations with genotyping and phenotyping to understand the dynamics of infection.
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Brotes de Enfermedades , Intoxicación Alimentaria por Salmonella/microbiología , Salmonella enterica/clasificación , Manipulación de Alimentos , Humanos , Italia/epidemiología , Intoxicación Alimentaria por Salmonella/epidemiología , Salmonella enterica/genéticaRESUMEN
Mycoplasma mycoides subsp. mycoides is the etiological agent of contagious bovine pleuropneumonia (CBPP). While several findings on CBPP prevalence in Nigeria were documented, no data were reported about the genomic characterization of Nigerian M. mycoides subsp. mycoides strains. Here, we present the draft genome sequences of two novel M. mycoides subsp. mycoides strains isolated in Nigeria.
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Porcine brucellosis occurs in many countries where pigs are farmed, often representing an underrated problem. B. suis biovar 2 is the most common isolate in Europe, with high prevalence reported in wild boars in which it is generally isolated in the absence of gross lesions. In the last five years, we tested for Brucella spp. 389 lymph nodes of wild boars collected during hunting seasons or during necropsy procedures. In this paper, we describe the first case of isolation of B. suis biovar 2 from a wild boar aborted foetus, and we analyse the genomic relationships with B.suis biovar 2 strains isolated in the past five years in Abruzzi Region, Central Italy. The genetic fingerprint revealed that the isolates under study belong to the MLST ST16 and to the MLVA11 Gt 57, similar to the Central-Eastern European strains. Massive restocking (for hunting purpose) of wild boars from Eastern Europe have been done since 1950 in Italy contributing to the increasing of population size and distribution, as well as to the interbreeding between these foreign breeds and the local population. The contamination of pastures with infected material such as aborted wild boars foetuses can increase the risk of transmission of Brucella among wild and domestic animals. The contact of B. suis with domestic ruminants may also cause serological reactions to brucellosis serological testing, and even unapparent infection, thus hampering the efforts made in the brucellosis eradication campaign.
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Brucella suis/clasificación , Brucella suis/genética , Brucelosis/veterinaria , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/microbiología , Animales , Análisis por Conglomerados , Europa (Continente) , Genotipo , Geografía , Italia/epidemiología , Tipificación de Secuencias Multilocus , Sus scrofa , PorcinosRESUMEN
Brucellosis is an important zoonosis caused by Brucella spp., still prevalent in most areas of the world. Brucellosis control in animals is the key to protect humans. The knowledge of Brucella spp. prevailing genotypes in a territory represents an important epidemiological tool to formulate policies and strategies for disease control and to trace back the introduction of new strains previously considered as exotic. In the last years, multiple-locus variable number tandem repeat analysis (MLVA) has been proposed as complementary to classical biotyping methods. MLVA may add important information to the classical epidemiological investigation techniques, to help in tracing back sources of infection in brucellosis outbreaks. Sardinia is an Italian region officially free from sheep and goats brucellosis since 1998. In 2011, Brucella melitensis biovar 1, a biotype not reported in Italy since 1995, was isolated in one flock in the region. The genotyping MLVA-16 showed that isolates belonged to a rare American lineage, confirming it was introduced from other countries. The strain was considered as probably originating from Spain, where this lineage is endemic. BrucellaMLVA-16 has been proved to be useful to analyse the epidemiological correlation of strains enabling to trace its geographic origin by comparing their previously reported genetic patterns.
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Brucella melitensis/genética , Brucelosis/veterinaria , Enfermedades de las Cabras/epidemiología , Tipificación de Secuencias Multilocus/veterinaria , Animales , Brucella melitensis/clasificación , Brucella melitensis/aislamiento & purificación , Brucelosis/epidemiología , Brucelosis/microbiología , Brucelosis/prevención & control , Control de Enfermedades Transmisibles/métodos , Femenino , Genotipo , Enfermedades de las Cabras/microbiología , Enfermedades de las Cabras/prevención & control , Cabras , Humanos , Italia/epidemiología , Masculino , Zoonosis/prevención & controlRESUMEN
The present study describes the use of microarray technology for rapid identification and differentiation of Mycoplasma mycoides subsp. mycoides from other mycoplasmas that may be pathogenic to ruminants, including those of the Mycoplasma mycoides cluster, genetically and antigenically strictly correlated with Mycoplasma mycoides subsp. mycoides. A microarray containing genetic sequences of 55 different bacterial species from Acholeplasma, Mycoplasma, Spiroplasma and Ureaplasma genera was constructed. Sequences to genes of interest were collected in FASTA format from NCBI. The collected sequences were processed with OligoPicker software. Oligonucleotides were then checked for their selectivity with BLAST searches in GenBank. The microarray was tested with ATCC/NCTC strains of Mycoplasma spp. of veterinary importance in ruminants including Mycoplasma belonging to the mycoides cluster as well as Mycoplasma mycoides subsp. mycoides and Mycoplasma mycoides subsp. capri field strains. The results showed that but one ATCC/NCTC reference strains hybridized with their species-specific sequences showed a profile/signature different and distinct from each other. The heat-map of the hybridization results for the nine genes interrogated for Mycoplasma mycoides subsp. mycoides demonstrated that the reference strain Mycoplasma mycoides subsp mycoides PG1 was positive for all of the gene sequences spotted on the microarray. CBPP field, vaccine and reference strains were all typed to be M. mycoides subsp. mycoides, and seven of the nine strains gave positive hybridization results for all of the nine genes. Two Italian strains were negative for some of the genes. Comparison with non-Mycoplasma mycoides subsp. mycoides reference strains showed some positive signals or considerable homology to Mycoplasma mycoides subsp. mycoides genes. As expected, some correlations were observed between the strictly genetically and antigenically correlated Mycoplasma mycoides subsp. mycoides and Mycoplasma mycoides subsp. capri strains. Specifically, we observed that some Italian Mycoplasma mycoides subsp. mycoides strains were positive for two out of the three Mycoplasma mycoides subsp. capri genes, differently from what has been observed for other European or African Mycoplasma mycoides subsp. mycoides strains. This study highlighted the use of microarray technology as a simple and effective method for a single-step identification and differentiation of Mycoplasma mycoides subsp. mycoides from other mycoplasmas that may be pathogenic to ruminants, including those of the Mycoplasma mycoides cluster, genetically and antigenically strictly correlated with Mycoplasma mycoides subsp. mycoides. The opportunity to discriminate several mycoplasmas in a single analysis enhances diagnostic rapidity and may represent a useful tool to screen occasionally mycoplasmas affecting animal farming in territories where diagnostic laboratory support is limited. The heat-map of the hybridization results of the comparative genomic hybridizations DNA-designed chip clearly indicates that the microarray performs well for the identification of the tested Mycoplasma mycoides subsp. mycoides reference and field strains, discriminating them from other mycoplasmas.
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Análisis por Micromatrices/veterinaria , Mycoplasma mycoides/clasificación , Mycoplasma mycoides/aislamiento & purificación , Mycoplasma/clasificación , Mycoplasma/aislamiento & purificación , Animales , Bovinos/microbiología , Cartilla de ADN , ADN Bacteriano/genética , Genes Bacterianos , Cabras/microbiología , Análisis por Micromatrices/métodos , Familia de Multigenes , Mycoplasma/genética , Mycoplasma mycoides/genética , Hibridación de Ácido Nucleico , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Análisis de Secuencia de ADN/veterinaria , Especificidad de la EspecieRESUMEN
The aim of this study was to assess the possible circulation of genetic resistance determinants and chromosomal point mutations in quinolone-resistant Escherichia coli isolated from livestock from central Italy. Forty-nine E. coli isolates were recovered from animals during the surveillance activities of the Istituto Zooprofilattico Abruzzo e Molise (IZSA&M), Italy, over 2 years. The plasmid resistance determinants and point mutations in DNA gyrase and topoisomerase IV were characterized by PCR and DNA sequencing. Of the 49 E. coli isolates, 34 were resistant to nalidixic acid, 4 to ciprofloxacin and 11 to nalidixic acid, ciprofloxacin and enrofloxacin. Chromosomal point mutations were found in gyrA gene (Ser83Leu and Asp87Asn) and gyrB (Gln434His, Lys444Arg and Gly435Val). We also report the simultaneous presence of qnrS1 quinolone resistance determinant, dfrA1-aadA22 gene cassettes and amino acid substitution Ser83Leu in the gyrA gene in an E. coli strain resistant only to nalidixic acid.