Search results for "Molecular epidemiology"
showing 10 items of 142 documents
Serological and molecular characteristics of Vibrio vulnificus biotype 3: evidence for high clonality.
2007
Vibrio vulnificus biotype 3 has been implicated as the causative pathogen of an ongoing disease outbreak that erupted in Israel in 1996. Recent work based on multi-locus sequence typing (MLST) showed that V. vulnificus biotype 3 is genetically homogeneous. The aim of this study was to investigate the existence of subpopulations within this homogeneous biotype by characterizing the surface antigens and analysing the sequence diversity of selected outer-membrane protein (OMP)-encoding genes. Rabbit antisera were prepared against biotype 1, 2 and 3 strains. The results of the slide-agglutination test, dot-blot assay (using fresh and boiled cells), and immunoblotting of lipopolysaccharides (LPS…
Epidemic dissemination of Salmonella enterica spp. enterica serovar Bovismorbificans in southern Italy in the years 1989-1991.
1994
Epidemic strains of Salmonella enterica subsp. enterica serovar Bovismorbificans isolated in southern Italy during the years 1989-1991 were submitted to a molecular epidemiological study in comparison with isolates identified in the years 1980-1988 in the same geographic area. Genomic DNA fragments obtained by digestion with BglI or Eco RI hybridized with Escherichia coli rRNA to produce three distinct, but highly related patterns. Ribotype 1, which had never been identified before 1989, was found to characterize most of the strains identified between 1989 and 1991. Such a finding supports the hypothesis of emergence and spread of a new bacterial clone associated with the increased number o…
Genotyping of bovine diarrhea virus (BVDV) isolated from cattle in Sicily
2011
Bovine Viral Diarrhoea - Mucosal Disease (BVD-MD) is a widely spread infectious disease that cause economically important losses in farms. Several epidemiological studies indicate a high genetic heterogeneity among Bovine Viral Diarrhoea Virus (BVDV) strains circulating in Italy. The aim of this study was to investigate the genotypes of BVDV in Sicily, a region in the South of Italy. For this purpose, 17 BVDV strains collected from cattle breed in Sicily between 2005 and 2008 were genetically typed by sequencing of 5'-untraslated region (5’-UTR) of the viral genome. In this study, phylogenetic analysis showed that all 17 examined strains were clustered within the BVDV genotype 1. Particular…
Molecular epidemiology of HIV-1 subtype B in the Basque Country (Spain)
2012
The goal of this work was to study the HIV-1 subtype B epidemic in the Basque Country (Spain). For this, we used HIV samples submitted for genotypic testing of anti-retroviral resistance mutations from 2005 until 2008. Consequently, 2115 HIV-1 sequences comprising protease and retrotranscriptase (PR/RT) coding regions were analyzed. HIV transmission groups were identified by phylogenetic analysis. The 10 largest such groups were subsequently subjected to Bayesian phylogenetic and coalescent reconstructions, using a relaxed molecular clock model. The results obtained show that these groups have been long-standing: most of them were originated in the late 70s or early 80s, and none after the …
Molecular Surveillance of HIV-1 in Madrid, Spain: a Phylogeographic Analysis ▿
2011
ABSTRACT The molecular epidemiology of HIV-1 is constantly changing, mainly as a result of human migratory flows and the high adaptive ability of the virus. In recent years, Spain has become one of Europe's main destinations for immigrants and one of the western European countries with the highest rates of HIV-positive patients. Using a phylogeographic approach, we have analyzed the relationship between HIV-1 variants detected in immigrant and native populations of the urban area of Madrid. Our project was based on two coincidental facts. First, resistance tests were extended to naïve and newly diagnosed patients, and second, the Spanish government legislated the provision of legal status t…
Sequential evolution of genotype GII.4 norovirus variants causing gastroenteritis outbreaks from 2001 to 2006 in Eastern Spain.
2008
Noroviruses are the most common cause of outbreaks of viral gastroenteritis worldwide. Norovirus outbreaks were surveyed in Catalonia and the region of Valencia (Eastern Spain) between January 2001 and December 2006 as part of the European Union funded network "Food-borne viruses in Europe". During this time the etiology and epidemiological features of 194 outbreaks of acute non-bacterial gastroenteritis were investigated and norovirus was identified as causing 169 (87.1%) of them. Molecular epidemiology of viral strains was studied by RT-PCR and sequencing part of the RNA polymerase gene in ORF1 from 153 outbreak strains. The most commonly identified norovirus genotype was GII.4 (71.9% of …
Patient-to-patient transmission of hepatitis C virus (HCV) during colonoscopy diagnosis
2010
Abstract Background No recognized risk factors can be identified in 10-40% of hepatitis C virus (HCV)-infected patients suggesting that the modes of transmission involved could be underestimated or unidentified. Invasive diagnostic procedures, such as endoscopy, have been considered as a potential HCV transmission route; although the actual extent of transmission in endoscopy procedures remains controversial. Most reported HCV outbreaks related to nosocomial acquisition have been attributed to unsafe injection practices and use of multi-dose vials. Only a few cases of likely patient-to-patient HCV transmission via a contaminated colonoscope have been reported to date. Nosocomial HCV infecti…
Estudios de epidemiología molecular en población inmigrante en España
2014
Fundamentos: La epidemiología molecular es una nueva disciplina que permite la integración de la información sobre la variabilidad genética de patógenos infecciosos con su difusión en la población y subgrupos de la misma incluyendo, por ejemplo, las mutaciones de resistencia a antibióticos y antivirales. El objetivo es conocer qué posibles diferencias existe en las características genéticas de los agentes infecciosos que afectan a las poblaciones inmigrante y autóctoctona en España. Métodos: Se revisaron artículos originales publicados entre 1998-2013, con las palabras clave "epidemiología molecular", "tipado molecular", "secuenciación", "inmigrante", "España". Resultados: De un total de 26…
ICUD-EAU International Consultation on Bladder Cancer 2012: Non–Muscle-Invasive Urothelial Carcinoma of the Bladder
2012
Item does not contain fulltext CONTEXT: Our aim was to present a summary of the Second International Consultation on Bladder Cancer recommendations on the diagnosis and treatment options for non-muscle-invasive urothelial cancer of the bladder (NMIBC) using an evidence-based approach. OBJECTIVE: To critically review the recent data on the management of NMIBC to arrive at a general consensus. EVIDENCE ACQUISITION: A detailed Medline analysis was performed for original articles addressing the treatment of NMIBC with regard to diagnosis, surgery, intravesical chemotherapy, and follow-up. Proceedings from the last 5 yr of major conferences were also searched. EVIDENCE SYNTHESIS: The major findi…
Respiratory Syncytial Virus: New Challenges for Molecular Epidemiology Surveillance and Vaccination Strategy in Patients with ILI/SARI.
2021
Several respiratory pathogens are responsible for influenza-like illness (ILI) and severe respiratory infections (SARI), among which human respiratory syncytial virus (hRSV) represents one of the most common aetiologies. We analysed the hRSV prevalence among subjects with ILI or SARI during the five influenza seasons before the emergence of SARS-CoV-2 epidemic in Sicily (Italy). Respiratory specimens from ILI outpatients and SARI inpatients were collected in the framework of the Italian Network for the Influenza Surveillance and molecularly tested for hRSV-A and hRSV-B. Overall, 8.1% of patients resulted positive for hRSV. Prevalence peaked in the age-groups <