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Introduction: Birds are involved in the epidemiology of several vector-borne viruses, as amplification hosts for viruses, dissemination vehicles for the vectors, and sources of emerging strains in cross-species transmission. Turkey provides diverse habitats for a variety of wild birds and is located along major bird migration routes. This study was undertaken to provide a cross-sectional screening of avian specimens for a spectrum of vector-borne viruses., Materials and Methods: The specimens were collected in Hatay province, in the Mediterranean coast of the Anatolian peninsula, located in the convergence zone of the known migration routes. Generic PCR assays were used for the detection of members of Nairovirus, Flavivirus, and Phlebovirus genera of Flaviviridae and Bunyaviridae families. The circulating viruses were characterized via sequencing and selected specimens were inoculated onto Vero cell lines for virus isolation., Results and Discussion: Specimens from 72 wild birds belonging in 8 orders and 14 species were collected. A total of 158 specimens that comprise 32 sera (20.3%) from 7 species and 126 tissues (79.7%) from 14 species were screened. Eight specimens (8/158, 5%), obtained from 4 individuals (4/72, 5.5%), were positive. West Nile virus (WNV) lineage 1 sequences were characterized in the spleen, heart, and kidney tissues from a lesser spotted eagle (Clanga pomarina), which distinctly clustered from sequences previously identified in Turkey. Toscana virus (TOSV) genotype A and B sequences were identified in brain and kidney tissues from a greater flamingo (Phoenicopterus roseus), a great white pelican (Pelecanus onocrotalus), and a black stork (Ciconia nigra), without successful virus isolation. Partial amino acid sequences of the viral nucleocapsid protein revealed previously unreported substitutions. This study documents the involvement of avians in WNV dispersion in Anatolia as well in TOSV life cycle.

An increased incidence of chronic kidney disease (CKD) after West Nile Virus (WNV) infections has been suggested but the association of WNV infections with renal damage remain inconclusive. This study was undertaken to characterize WNV infections in individuals with acute kidney injury (AKI) and CKD, and to evaluate hemodialysis as a probable transmission route. A total of 463 plasma and urine samples were collected from 45 AKI and 77 CKD patients. Nested and real-time polymerase chain reaction (PCR) assays were employed for viral RNA detection. Specific immunoglobulins were investigated via immunofluorescence and plaque reduction neutralization assays. Consecutive pre and post-dialysis samples were evaluated in CKD cases. WNV RNA and specific immunoglobulins were detected in 7 (5.7%) and 5 (4.1%) individuals, respectively. The AKI patients with WNV RNA in blood and urine had underlying diseases requiring immunosuppressive therapy and demonstrated moderate to high viral loads. No clinical symptom related to WNV infection were observed in CKD cases with detectable viral nucleic acids. All WNV sequences were characterized as lineage 1 clade 1a and several amino acid substitutions with unknown impact were noted. Detailed epidemiologic investigation of WNV RNA positive CKD cases revealed probable vector-borne virus exposure, without the evidence for transmission via hemodialysis., (© 2015 Wiley Periodicals, Inc.)

We sequenced West Nile viruses (WNVs) from Turkey and found close relationships to WNV lineage 1 strain ArB310/67 from the Central African Republic, distinct from other WNVs circulating in the Mediterranean Basin, eastern Europe, and the Middle East. These findings suggest independent introductions of WNV strains from Africa to the Middle East.

Toscana virus (TOSV), West Nile virus (WNV) and tickborne encephalitis virus (TBEV) are among major viral pathogens causing febrile disease and meningitis/encephalitis. The impact of these viruses was investigated at a referral centre in Ankara Province, Central Anatolia in 2012, where previous reports suggested virus circulation but with scarce information on clinical cases and vector activity. Serum and/or cerebrospinal fluid samples from 94 individuals were evaluated, in addition to field-collected arthropod specimens that included 767 sandflies and 239 mosquitoes. Viral nucleic acids in clinical samples and arthropods were sought via specific and generic nested/real-time PCRs, and antibody responses in clinical samples were investigated via commercial indirect immunofluorescence tests (IIFTs) and virus neutralization. A WNV antigen assay was also employed for mosquitoes. WNV neuroinvasive disease has been identified in a 63-year-old male via RNA detection, and the WNV strain was characterized as lineage 1. TOSV infections were diagnosed in six individuals (6.3%) via RNA or IgM detection. Partial sequences in a 23-year-old female, presented with fever and transient pancytopenia, were characterized as TOSV genotype A. Febrile disease with arthralgia and/or peripheral cranial nerve involvement was noted in cases with TOSV infections. Previous WNV and TOSV exposures have been observed in 5.3% and 2.1% of the subjects, respectively. No confirmed TBEV exposure could be identified. Morphological identification of the field-collected mosquitoes revealed Culex pipiens sensu lato (74.4%), Anopheles maculipennis (20.9%), An. claviger (2.1%) and others. Sandfly species were determined as Phlebotomus papatasi (36.2%), P. halepensis (27.3%), P. major s. l. (19.3%), P. sergenti (8.9%), P. perfiliewi (4.4%), P. simici (2.6%) and others. Viral infections in arthropods could not be demonstrated. TOSV genotype A and WNV lineage 1 activity have been demonstrated as well as serologically proven exposure in patients. Presence of sandfly and mosquito species capable of virus transmission has also been revealed., (© 2013 Blackwell Verlag GmbH.)

West Nile virus (WNV), a mosquito-borne flavivirus with significant impact on human and animal health, has recently demonstrated an expanded zone of activity globally. The aim of this study is to investigate the frequency and distribution of WNV infections in potential vectors and several mammal and avian species in Turkey, where previous data indicate viral circulation. The study was conducted in 15 provinces across Turkey during 2011-2013. In addition, the entomological study was extended to 4 districts of the Turkish Republic of Northern Cyprus. WNV exposure was determined in humans, horses, sheep and ducks from Mersin, Sanliurfa, Van and Kars provinces of Turkey, via the detection of neutralizing antibodies. WNV RNA was sought in human and equine samples from Mersin, Adana and Mugla provinces. Field-collected mosquitoes from 92 sites at 46 locations were characterized morphologically and evaluated for viral RNA. Neutralizing antibodies were identified in 10.5% of the 1180 samples studied and detected in all species evaluated. Viral nucleic acids were observed in 5.9% of 522 samples but only in horses. A total of 2642 mosquito specimens belonging to 15 species were captured, where Ochlerotatus caspius (52.4%), Culex pipiens sensu lato (24.2%) comprise the most frequent species. WNV RNA was detected in 4 mosquito pools (1.9%), that comprise Oc. caspius Cx. pipiens s.l. and DNA barcoding revealed the presence of Cx. quinquefasciatus and Cx. perexiguus mosquitoes in infected Culex pools. All WNV partial sequences were characterized as lineage 1 clade 1a. These findings indicate a widespread WNV activity in Turkey, in Eastern Thrace and Mediterranean-Aegean regions as well as Southeastern and Northeastern Anatolia.

The objective of this study was to identify the impact of West Nile virus (WNV) and Toscana virus (TOSV) in febrile diseases of unknown aetiology in Eastern Thrace, Turkey; this study was conducted during August-October 2012, and included 18 clinical cases and 296 blood donors for local serosurveillance. Antibodies were determined via commercial assays and further tested for specificity via neutralization assays (NA). Viral RNAs were sought via specific and/or generic primers. WNV infections were diagnosed in seven patients (38.8%), detected via RNA+IgM in four, RNA in one and IgM and low avidity IgG in two cases. The most common symptom was fever (>38°C), followed by headache, malaise/fatigue, myalgia/arthralgia, muscle stiffness/lower back pain, anorexia, nausea/vomiting, diarrhoea, supraorbital/retrobulbar pain and abdominal pain. Neurological symptoms were noted in one individual. WNV strains in RNA-detectable patients were characterized as lineage 1. TOSV RNA or IgM were identified in two individuals with confirmed WNV infections and in one patient without evidence of WNV exposure. The clinical and laboratory findings in individuals with WNV/TOSV co-infection were comparable to those in WNV-induced disease. The TOSV strain in the patient with detectable viral RNA was characterized as genotype A. In local blood donors, seroreactivity for specific WNV and TOSV immunoglobulins was observed in 1.7% (5/296) and 14.4% (26/180), respectively. These findings indicate the emergence of WNV and TOSV-associated diseases in Eastern Thrace. WNV/TOSV co-infections were documented for the first time., (© 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.)

Introduction: Arbovirus screening in invertebrate vectors is an important component of the vector-borne disease surveillance programs. Turkey has been shown to harbor medically important mosquito-borne arboviruses such as West Nile Virus (WNV). However, limited information about infections in vectors are currently available. This study was performed to provide preliminary data from Eastern Thrace region, Turkey, where no arbovirus vector surveillance has previously been performed., Materials and Methods: Mosquito sampling was undertaken at 23 sites in Edirne province during July, 2012. All specimens were identified morphologically, and selected individuals were subjected to DNA barcoding via cytochrome c oxidase I (COI) sequencing. Consensus PCR for Flavivirus, Alphavirus, and Phlebovirus genera and WNV-specific nested and real-time reverse transcription PCR were employed for mosquito pool screening and/or confirmation. Viral sequences detected in pools were characterized via sequencing., Results: A total of 9261 mosquitoes were captured and distributed into 232 pools from the following species: Ochlerotatus caspius (90.9%), Culex pipiens sensu lato (s.l.) (4.7%), Anopheles pseudopictus (3%), and Anopheles maculipennis s.l. (1.3%). Specimens morphologically classified as Cx. pipiens s.l. were identified as Cx. pipiens pipiens via barcoding. Thirty-seven mosquito pools (15.9%) were positive in pan-flavivirus and WNV-specific assays. Viral sequences in positive pools were characterized as WNV lineage 1 clade 1a and demonstrated 1-4% divergence. No flavivirus sequences other than WNV were detected in the mosquito pools. WNV infection rates in Oc. caspius and Cx. pipiens s.l. pools were 15.6% and 36.3%, respectively. Comparison of current and previously identified WNV sequences from Turkey revealed 94.00-96.34% similarity., Discussion: WNV RNA was identified for the first time in Cx. pipiens s.l. and Oc. caspius mosquitoes in Eastern Thrace, Turkey. Our findings indicate the circulation of WNV lineage 1 strains in potential vector species and provide an epidemiological link between WNV activity in mosquitoes and vertebrate infections.

Background: West Nile fever is an important zoonotic infection caused by West Nile virus (WNV), a member of the Flaviviridae. Previous serological data from Turkey suggest widespread WNV circulation. This report includes cases of human and equine WNV infections occurring concurrently, and manifesting as central nervous system infections, in two neighboring provinces of Central Anatolia, Turkey. A partial phylogenetic analysis of the causative virus is given for the first time., Methods: The cases were reported in February (horses) and March (human). Symptoms of the disease were similar in the two species, characterized by neurological manifestations suggesting meningoencephalitis. Real-time/nested PCRs and commercial immunoassays and a plaque reduction neutralization assay were employed for the detection of viral RNA and specific antibodies, respectively., Results: WNV RNAs were detected in buffy coat (horses) and cerebrospinal fluid (human) samples. Partial nucleotide sequences of the E-gene coding region revealed that the strains are closely related to viruses of lineage 1, clade 1a. Accompanying equine serosurveillance demonstrated WNV-specific antibodies in 31.6% of the samples., Conclusions: This is the first report of acute WNV infections caused by lineage 1 strains from Turkey, in concordance with previous reports from some European and North African countries., (Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Objectives: Flavi- and Phleboviruses associated with central nervous system (CNS) infections including West Nile Virus (WNV), Tick-borne Encephalitis Virus (TBEV) and Toscana Virus (TOSV) cause significant morbidity and mortality in humans. In this study, the impact of these agents have been investigated in CNS infections at referral hospitals in two provinces in Turkey, where circulation of these viruses have previously been recognized., Methods: In the study, 258 samples from 126 individuals from Ankara and 113 samples from 108 individuals from Izmir provinces collected in 2010 were included. Viral RNAs were investigated by multiple genus and strain specific primers. Commercial serological assays were employed in screening and reactive results were evaluated with additional assays and by plaque reduction neutralization assay., Results: Two cases of WNV CNS infections, 14 cases of TOSV infections and one TBEV-exposed individual were identified via serological testing. WNV infections in 61 and 56-year old individuals from Ankara presented with fever and encephalitis without skin rash and residual neurologic damage. TOSV-associated cases from both provinces mainly displayed signs of meningitis. TOSV exposure was documented for the first time from Izmir., Conclusions: WNV, TBEV and TOSV infections must be considered in cases of meningoencephalitis of unknown etiology in Turkey., (Copyright © 2012 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

West Nile virus (WNV) and tick-borne encephalitis virus (TBEV) are among the medically important Flaviviruses that cause significant morbidity and mortality in humans. In this study, seroprevalence of WNV and TBEV in sera from two state medical hospitals from the southeastern part of Turkey was investigated. One hundred eighty-one serum samples were evaluated for WNV immunoglobulin G (IgG) by an indirect immunofluorescence test (IIFT) and for IgG antibodies against TBEV by a commercial enzyme-linked immunosorbent assay (ELISA) kit with enhanced sensitivity and specificity. Sera positive for WNV IgG were further analyzed by plaque reduction neutralization assay (PRNA). TBEV IgM was also investigated by ELISA in all seroreactive samples. Of 181 sera, 29 (16%) were positive for WNV IgG by IIFT and 17 of 179 (9.5%) were confirmed by PRNA. Nineteen of 181 (10.5%) sera were detected to have TBEV IgG. Mean titer of TBEV IgG was 43.0 RU/mL (median, 33.9 RU/mL; cutoff: 20 RU/mL). Four samples with WNV IgG antibodies were also positive for TBEV IgG antibodies. TBEV IgM was detected in 9 of 39 (23%) of all seroreactive sera, where IgM positivity were accompanied by IgG for 6 samples. These results suggest the presence of possible human WNV and TBEV infections in southeastern Turkey where vector activity have previously been detected.