Sandfly fever viruses (SFVs) cause febrile diseases as well as aseptic meningitis/encephalitis and include serotypes sandfly fever Sicilian virus (SFSV), sandfly fever Naples virus (SFNV) and Toscana virus (TOSV). Infections are endemic in the Mediterranean basin and data on SFV activity in Turkey are limited. In this study, sera from 1533 blood donors from the Ankara, Konya, Eskisehir and Zonguldak provinces of Turkey were evaluated for SFV exposure by indirect immunofluorescence test (IIFT) and confirmed by virus neutralization test (VNT). One hundred and two patients with central nervous system (CNS) infections of unknown aetiology were also tested via IIFT and real-time reverse-transcription PCR for SFV/TOSV. Rate of overall IgG reactivity in IIFT was 32.9% (505/1533) among blood donors. TOSV exposure was confirmed by VNT in all study regions. Exposure to the recently-identified serotype sandfly fever Turkish virus, as evaluated by VNT, was revealed in Konya and Ankara. SFNV exposure was identified in Konya and SFSV was observed to be present in all regions except Zonguldak. TOSV RNA was detected in 15.7% (16/102) and was accompanied by TOSV IgM in 25% (4/16) of the patients. Partial L and S sequences suggested that TOSV circulating in Turkey can be grouped into TOSV genotype A strains. Exposure to TOSV and other SFV serotypes was revealed in blood donors and CNS infections by TOSV were identified for the first time in Turkey. Infections are observed to be endemic in central Anatolia and should be considered as aetiologic agents in cases/outbreaks of fever and meningoencephalitis.
Toscana virus (TOSV), a sandfly fever virus serotype of medical and public health importance, is a major pathogen involved in aseptic meningtis occurring in Mediterranean countries and poses a threat to the residents as well as travellers. Limited data on TOSV activity are present from Turkey despite being located in the endemic zone. We aimed to identify TOSV exposure in 1115 healthy blood donors at the Hacettepe University Hospital Blood Bank in Ankara, Turkey, using commercial indirect fluorescence assays (IFAs) and virus neutralization test (VNT) for antibody detection and specificity confirmation. A total of 199 samples (17.8%) were positive for anti-TOSV that include IgG reactivity in 10.4%, IgM reactivity in 8.2% and IgM + IgG reactivity in 0.7% of the sera. Anti-TOSV specificity could be confirmed via VNT in 56% of the IgG- and 43.6% of the IgM-positive sera, making up a total of 58 samples (5.2%). Risk factors associated with TOSV IgG reactivity were male gender, residing in rural areas, frequent sighting of mosquitoes/sandflies and working outdoors. TOSV-specific antibody prevalence increased significantly with age. Evidence of exposure to other sandfly fever viruses was noted. These data reveal that mild or asymptomatic infections with TOSV are frequent in central and northern Anatolia. TOSV exposure has also been identified in residents of 9 provinces in southern/southeastern Anatolia for the first time.
Introduction: Sandfly fever virus (SFV) serotypes sandfly fever Naples virus, sandfly fever Sicilian virus, and sandfly fever Cyprus virus cause febrile diseases, whereas Toscana virus (TOSV) is responsible for aseptic meningoencephalitis. Diagnosis and surveillance of TOSV depend heavily on virus serology, and various commercial assays utilizing various antigen sources and formats have been available. The aim of this study was to perform comparative evaluation of commercially available serological assays for anti-TOSV immunoglobulins. Materials and Methods: A collection of 120 sera from healthy blood donors from an endemic region, previously identified to be reactive for antibodies against various SFV serotypes by indirect immunofluorescence test (IIFT), was reevaluated for IgG/IgM via IIFT, enzyme-linked immunosorbent assay, and an immunoblot assay manufactured by Euroimmun, Diesse, and Mikrogen, respectively. Virus neutralization test (VNT) was performed for 99 sera using standard TOSV, sandfly fever Sicilian virus, and sandfly fever Naples virus strains. Results: A total of 89 samples (74.2%) were reactive for TOSV IgG in at least one of the commercial assays, and 31 samples (31.3%) were reactive in VNT for various SFV serotypes. Average percentage agreements among commercial assays and between VNT and the commercial assays were noted as 57.8% and 62.6%, respectively. No significant correlation between assay results and VNT titers was observed. SFV IgM antibodies were detected in a total of eight samples (6.7%) via IIFT, which were nonreactive in enzyme-linked immunosorbent assay and VNT. Discussion: Commercial diagnostic immunoassays displayed slight to fair agreement for TOSV IgG as assessed via kappa and percentage agreement values. The results could only be confirmed via virus neutralization in a portion of the samples, and overall agreement between the commercial assays and VNT was slight. Commercial assays such as immunoblot can be used in addition to VNT for confirmation of TOSV exposure.
WNV exposure is confirmed in 0.56% of the tested healthy blood donors in Central Anatolia, with evidence for dengue/yellow fever and/or other flaviviral infections. This study is the first to document WNV exposure in individuals from Konya, Yozgat, and Sivas provinces in Central Anatolia, and it also establishes viral activity in Ankara, the capital of Turkey.
This study aimed to determine the presence of vancomycin resistance (vanA and vanB) and virulence genes (esp, asa1, gelE, ace, hyl, cylA, cpd and ebpA) in vancomycin-resistant Enterococcus faecium (VREfm) strains and to analyse the clonal relationships among the strains. E. faecium strains were identified from rectal and clinical specimens by biochemical tests and the API-20 Strep kit. Susceptibility testing was performed using disc-diffusion and broth-dilution methods. PFGE was used for molecular typing of the VREfm strains. The vancomycin resistance and virulence genes were amplified by two-step multiplex PCR. All 55 VREfm isolates were resistant to penicillin G, ampicillin and high-level gentamicin but were susceptible to quinupristin/dalfopristin and linezolid. Multiplex PCR analysis indicated that all isolates harboured vanA and that 41 (75 %) were positive for virulence genes. The esp gene was the most common virulence factor and was detected in nine (41 %) invasive and 32 (96.7 %) non-invasive isolates. Multiple virulence genes were observed only in two non-invasive isolates; one harboured esp and ebpA and the other harboured esp, ebpA, asa1, gelE and cpd. PFGE typing yielded 16 different types, seven of which were clusters with two to 14 strains each. The clustering rates of the rectal swab, blood and urine isolates were 72.7 %, 61.5 % and 87.5 %, respectively. The genetic similarity observed among the VREfm isolates indicated crosstransmission in the hospital. Further studies on the virulence factors present in the strains might provide insight into the acquisition of these traits and their contribution to increased prevalence of VREfm.
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