Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Med Vet Entomol ; 38(2): 205-215, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38348507

RESUMO

This study aims to determine the phenological characteristics of thermal responses in the larvae of a Culex pipiens complex field population at the individual level under the influence of thermal regime of its habitat. The analysis is based on a structured population model quantifying the thermal responses of development time and survival under variable conditions and characterising the variety between the larvae (interindividual variety). During the study performed in Turkish Thrace on a monthly basis between May 2021 and June 2022, a total of 3744 larvae were reared as peer larval cohorts and 2330 larvae as siblings in artificial containers to be fully exposed to the natural thermal condition that was recorded hourly. The development process of larvae was monitored daily from egg to adult. As a result, a total of 4788 adult mosquitoes emerged, with a development period ranging from 8 to 52 days in the females and 7 to 50 days in the males, and the survival rate was found to range from 0% to 100%. Both parameters varied by month and individuals, and the variations manifested itself, particularly in the colder periods. The results indicate that the variation between the individuals in terms of thermal response in the larvae of C. pipiens, along with the thermal acclimation ability, appears to be fate determinant in resisting fluctuating thermal regimes, surviving in concurrent climate change and adapting to new conditions with modifications in the seasonal phenology, such as maintaining reproductive dynamics throughout the winter thanks to global warming.


Assuntos
Culex , Larva , Animais , Culex/fisiologia , Culex/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Feminino , Masculino , Turquia , Aclimatação , Temperatura
2.
Parasitol Res ; 123(1): 37, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38087074

RESUMO

This study was carried out at a vital stopover site of migrating birds in the Turkish Thrace, European part of Turkey, on the Mediterranean/Black Sea Flyway. Ticks were collected from the birds captured in the four migration periods, i.e., autumn 2020, spring 2021, autumn 2021, and spring 2022, and identified morphologically. Throughout the study, 10,651 birds from 77 species were examined, and 671 belonging to 34 species were found infested. The infestation prevalence in total birds and the mean number of ticks per infested bird were 6.3% and 3.8 (range: 1-142), respectively. A total of 2573 ticks were collected with the following species distribution and numbers: Ixodes spp. 70 larvae, I. frontalis 1829 larvae, 337 nymphs, and 30 adults, I. acuminatus 16 nymphs and 42 adults, I. ricinus 39 larvae, 141 nymphs, and one adult, Hyalomma spp. seven larvae and 60 nymphs, and Haemaphysalis sp. one larva. Prevalence, intensity, and species distribution of the ticks in birds varied depending on the month, season, year, and species-specific migration phenology of the birds. The results show that precise determination of the tick-borne risk associated with migratory birds for a particular region necessarily requires long-term and comprehensive studies and indicates that anthropogenic climate change and habitat degradation can significantly differentiate the risk by influencing the migration phenology in birds and by making new regions suitable for the establishment of different ticks.


Assuntos
Doenças das Aves , Ixodes , Ixodidae , Infestações por Carrapato , Animais , Doenças das Aves/epidemiologia , Aves , Larva , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Turquia/epidemiologia , Migração Animal
3.
Vector Borne Zoonotic Dis ; 23(10): 528-536, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37527191

RESUMO

Background: Istanbul is one of the world's most densely populated metropolitan cities, with various geographical areas that possess distinct characteristics. These areas have different climates, vegetation, and host populations that can support the survival of diverse tick species. Turkey is a region with a high risk of Crimean-Congo hemorrhagic fever (CCHF) disease, making it crucial to screen for this risk, especially in densely populated regions such as Istanbul and its surrounding areas. However, the presence of potential vectors for CCHF virus (CCHFV) in these areas has not been studied in the past 12 years. Materials and Methods: In this study, a total of 676 ticks were collected from 6 centers using the flagging and dragging method. Ticks were identified as Ixodes ricinus (7.85%), Ixodes spp. immature form (73.22%), Haemaphysalis parva (0.89%), Haemaphysalis inermis (0.15%), and Haemaphysalis spp. immature form (17.89%). Pooled samples were screened for the CCHFV genome (S segment) by RT-nested PCR. Results: A total of 14.28% of the samples were found as positive. Phylogenetic analysis revealed that all the CCHFV sequences obtained from the positive samples were clustered in clade V: Europe/Turkey genogroup. Conclusion: This study suggests that ixodes spp. and Haemaphysalis spp. may have the potential to pose a biorisk for Crimean-Congo hemorrhagic fever.

4.
Sci Rep ; 12(1): 14773, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042343

RESUMO

Several animal species, including ants, have been reported to be capable of predation on ticks. However, determining factors in most interactions between ticks and predators have not yet been fully deciphered. We hypothesized that the ant species Lasius alienus, which is unknown whether it has any impact on ticks, may exhibit predation on the eggs of tick species Hyalomma marginatum, H. excavatum, and Rhipicephalus bursa, and that the tick egg wax can be the main determinant in possible predation. In the study, 6300 tick eggs with the natural wax coating (waxed/untreated) and 2700 dewaxed tick eggs, the wax of which was removed in the laboratory, were repeatedly presented to the foraging workers belonging to three different ant nests in their natural habitat. Depending on the tick species and trials, the rate of the eggs carried by the ants ranged from 12.8 to 52.1% in the waxed and from 59.8 to 78.4% in the dewaxed eggs. It was observed that the dewaxing process both increased the interest of the ants in the eggs and resulted in a reduction in the variation associated with tick species. This study showed that L. alienus has a predatory effect on tick eggs, the severity of this impact is closely associated with the tick species, the tick-associated difference is caused by the species-specific property of the egg wax, and the variety in the protective effects of the wax seems to be an evolutional result of the biological and ecological adaptation process of the species.


Assuntos
Formigas , Ixodidae , Rhipicephalus , Animais , Comportamento Predatório , Especificidade da Espécie
5.
Parasitol Res ; 120(10): 3395-3404, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34480201

RESUMO

The first etiologically confirmed cases of Crimean-Congo hemorrhagic fever (CCHF) in humans were detected in Turkey in 2002. Since then, thousands of cases have been reported from different parts of the country. Hyalomma (Hy.) marginatum is considered the main vector tick of CCHFe in Turkey, and the primary infection route for humans is known to be the tick bite. This study was carried out between January 2013 and December 2014 in Thrace, Turkey, to determine monthly prevalence and intensity of tick infestation in cattle and, ultimately, to predict the related risk of human exposure to ticks and tick-borne diseases. During the study, 1,701 cattle in 24 villages were screened for ticks; 24,012 adult ticks, 1,887 nymphs, and 766 larvae were encountered on 1,228 of these cattle. On the 1,318 cattle that routinely grazed in the daytime, Hy. marginatum was the most predominant species, with an infestation prevalence of 73.6% and an average tick intensity of 16.1 on the infested cattle. In order of prevalence (%) in the grazing cattle, Hy. marginatum was followed by Rhipicephalus (R.) bursa (32.7%), R. turanicus (%29.5), Ixodes (I.) ricinus (15.1%), Haemaphysalis (Ha.) parva (10.4%), Ha. inermis (10%), Ha. punctata (6.5%), and Dermacentor (D.) marginatus (2.3%). The obtained data were discussed in terms of the infestation characteristics of the observed tick species, the drivers that may affect these characteristics, and the features of possible relationship between Hy. marginatum infestation in the cattle and CCHF cases among humans in the area.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Ixodidae , Rhipicephalus , Animais , Bovinos , Febre Hemorrágica da Crimeia/epidemiologia , Febre Hemorrágica da Crimeia/veterinária , Turquia/epidemiologia
6.
Parasitol Int ; 85: 102427, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34314861

RESUMO

The one-host biological north form / ecotype of Hyalomma scupense Schulze, 1919 (Acari, Ixodidae) is reported for the first time in Turkey herein. Following the first detection of the tick, a longitudinal field study was carried out to fill gaps in the data concerning its biological features. This study also aimed to determine how the monthly activation dynamics of this relatively cold climate-adapted species is characterized under the influence of the warm summer subtype of the Mediterranean climate. During this study, which was carried out on a monthly basis in 2014, H. scupense was found on cattle from 5 out of 18 villages screened in Thrace (the European part of Turkey). The field study revealed that i) this north ecotype of H. scupense exhibits winter one-host behavior beginning in October (with larval stages) and ending in April (with engorged adults); ii) engorged females detach from the cattle, drop on the floors of barns during night and accumulate on piled bedding contaminated with slurry manure; iii) in the late spring, engorged females lay eggs, and larvae hatch in the same area; and iv) larvae become active in autumn as the weather grows cooler. The results indicated that although one-host H. scupense is known to be distinctly adapted to cold conditions, it can also be effectively established in relatively temperate regions and complete its life cycle with some modifications in the timing of its monthly activation dynamics.


Assuntos
Doenças dos Bovinos/epidemiologia , Ixodidae/fisiologia , Infestações por Carrapato/veterinária , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Clima , Feminino , Interações Hospedeiro-Parasita , Temperatura Alta , Ixodidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Dinâmica Populacional , Estações do Ano , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Turquia/epidemiologia
7.
Viruses ; 13(2)2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572847

RESUMO

Currently, next generation sequencing (NGS) is the mainly used approach for identification and monitorization of viruses with a potential public health threat in clinical and environmental samples. To facilitate detection in NGS, the sequence-independent, single-primer-amplification (SISPA) is an effective tool for enriching virus sequences. We performed a preliminary assessment of SISPA-nanopore sequencing as a potential approach for screening tick-borne viruses in six specimens with detectable Crimean-Congo hemorrhagic fever virus (CCHFV) and Jingmen tick virus (JMTV) sequences. A comparison of unbiased NGS and SISPA followed by nanopore sequencing was carried out in 4 specimens with single and pooled ticks. The approach was further used for genome sequencing in culture-grown viruses. Overall, total/virus-specific read counts were significantly elevated in cell culture supernatants in comparison to single or pooled ticks. Virus genomes could be successfully characterized by SISPA with identities over 99%. Genome coverage varied according to the segment and total read count. Base calling errors were mainly observed in tick specimens and more frequent in lower viral loads. Culture-grown viruses were phylogenetically-related to previously-reported local viruses. In conclusion, the SISPA + nanopore sequencing was successful in generating data comparable to NGS and will provide an effective tool for broad-range virus detection in ticks.


Assuntos
Arbovírus/isolamento & purificação , Primers do DNA/genética , Sequenciamento por Nanoporos/métodos , Carrapatos/virologia , Animais , Arbovírus/genética , Flaviviridae/genética , Flaviviridae/isolamento & purificação , Genoma Viral/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia
8.
Ticks Tick Borne Dis ; 12(2): 101622, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33388553

RESUMO

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral disease in the old continents, in many countries south of the 50 °North Parallel. The agent is known to be the most prevalent and major cause of severe and fatal human hemorrhagic diseases among the tick-borne viruses, and is the second most widespread of all medically critical arboviruses following dengue. Members of the Hyalomma genus are mainly involved in the natural transmission of the CCHF virus (CCHFV); of those, H. marginatum is known to be the primary vector of the disease in the Western Palaearctic. In general, epidemiological studies have been based on serological detections in the hosts and/or virus screening of ticks collected from the hosts. To the best of our knowledge, only a few studies have been carried out to screen the virus in unfed, questing field ticks. Nevertheless, detection of the virus in questing ticks is known to be a crucial parameter to determine the possible vector roles of the ticks and to understand the ecological dynamics of related diseases. In this study, 200 (75 males,125 females) questing H. marginatum adults collected from the field in nine villages in Thrace, located in the European part of Turkey, were screened individually for CCHFV using nested PCR. As a result, 103 (51.5 %) ticks were determined as positive with various strains of CCHFV. High positivity in questing vectors in a region where a significantly lower number of human cases have been encountered suggests that there should be some region-specific drivers that are effective in the natural dynamics of the disease. Detailed etiological and epidemiological studies are needed to reveal the possible reason for this unexpected discrepancy.


Assuntos
Genoma Viral , Genótipo , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Ixodidae/virologia , Animais , Feminino , Vírus da Febre Hemorrágica da Crimeia-Congo/classificação , Masculino , Filogenia , Turquia
9.
Ticks Tick Borne Dis ; 11(5): 101448, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32723637

RESUMO

We conducted orthonairovirus RNA screening of 7043 tick specimens-representing 16 species-collected from various regions of Anatolia. In 602 pools, Crimean-Congo hemorrhagic fever virus (CCHFV) Europe 1 and 2 lineages were detected in seven pools (1.1 %) comprising Hyalomma marginatum, Hyalomma scupense, Rhipicephalus bursa, Rhipicephalus sanguineus sensu lato and Rhipicephalus turanicus ticks. In pools of Hyalomma aegyptium, we detected Tamdy virus (TAMV) and an unclassified nairovirus sequence. Next-generation sequencing revealed complete coding regions of three CCHFV Europe 2 (AP92-like) viruses, TAMV and the novel orthonairovirus, tentatively named herein as Meram virus. We further performed in silico functional analysis of all available CCHFV Europe 2, TAMV, Meram and related virus genomes. The CCHFV Europe 2 viruses possessed several conserved motifs, including those with OTU-like cysteine protease activity. Probable recombinations were identified in L genome segments of CCHFV and TAMV. Through phylogeny reconstruction using individual genome segments, Meram virus emerged as a distinct virus among species within the Orthonairovirus genus. It further exhibited conserved motifs associated with RNA binding, encapsidation, signal peptidase cleavage, post-translational modification, RNA-dependent RNA polymerase and OTU-like activities. Bole tick virus 3 was also detected in two pools with CCHFV reactivity. Hereby, we describe a novel tick-associated orthonairovirus, in a CCHFV-endemic region with confirmed TAMV activity. Human and animal health impact of these viruses need to be addressed.


Assuntos
Genoma Viral , Ixodidae/virologia , Nairovirus/isolamento & purificação , Animais , Simulação por Computador , Feminino , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Ixodidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/virologia , Masculino , Nairovirus/classificação , Nairovirus/genética , Ninfa/crescimento & desenvolvimento , Ninfa/virologia , Filogenia , Rhipicephalus/crescimento & desenvolvimento , Rhipicephalus/virologia , Turquia
10.
Parasit Vectors ; 13(1): 201, 2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32307010

RESUMO

BACKGROUND: Recent reports have demonstrated the presence of Crimean-Congo hemorrhagic fever virus (CCHFV) genomic material in Hyalomma aegyptium ticks feeding primarily on tortoises belonging to the genus Testudo. This raises the question if these ticks and their hosts play a role in the natural transmission dynamics of CCHFV. However, the studies are limited, and assessing the relevance of H. aegyptium in perpetuating the virus in nature, and a potential spillover to humans remains unknown. This study aimed to detect CCHFV in H. aegyptium ticks and their tortoise hosts in the East Thrace region of Turkey, where H. aegyptium is the most common human-biting tick and where a high density of tortoises of the genus Testudo can be found. METHODS: During the study period, 21 blood samples from different tortoises (2 T. hermanni and 19 T. graeca), 106 tick pools (containing 448 males, 152 females, 93 nymphs and 60 larvae) collected from 65 tortoises (5 T. hermanni and 60 T. graeca), 38 adult unfed questing ticks (25 males and 13 females, screened individually) and 14 pools (containing 8 nymphs and 266 larvae) of immature unfed questing ticks collected from the ground were screened for CCHFV genome by nested PCR and partial genomes sequenced. RESULTS: As a result of the screening of these 179 samples, 17 (9.5%) were detected as positive as follows: 2 of 21 blood samples (9.52%), 13 (containing 18 nymphs in 3 pools, and 52 males and 8 females in 10 pools) of 106 tick pools from tortoises (12.26%), and 2 of 38 adult questing ticks (5.26%). No positive result was determined in 14 pools of immature questing ticks. CONCLUSIONS: Previous studies have shown that reptiles can participate in the transmission of arthropod-borne viruses, but they may contribute to different aspects of the disease ecology and evolution of tick-borne viral pathogens. Our results indicate the presence of CCHFV in questing and feeding H. aegyptium ticks as well as tortoise hosts. This may indicate that CCHFV circulates in a cryptic transmission cycle in addition to the primary transmission cycle that could play a role in the natural dynamic of the virus and the transmission to humans.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia/transmissão , Carrapatos/virologia , Tartarugas/virologia , Zoonoses/virologia , Animais , Vetores Aracnídeos/virologia , DNA Viral , Reservatórios de Doenças/virologia , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Turquia/epidemiologia , Tartarugas/parasitologia
11.
Viruses ; 11(11)2019 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-31744216

RESUMO

We obtained a Jingmen tick virus (JMTV) isolate, following inoculation of a tick pool with detectable Crimean-Congo hemorrhagic fever virus (CCHFV) RNA. We subsequently screened 7223 ticks, representing 15 species in five genera, collected from various regions in Anatolia and eastern Thrace, Turkey. Moreover, we tested specimens from various patient cohorts (n = 103), and canine (n = 60), bovine (n = 20) and avian specimens (n = 65). JMTV nucleic acids were detected in 3.9% of the tick pools, including those from several tick species from the genera Rhipicephalus and Haemaphysalis, and Hyalomma marginatum, the main vector of CCHFV in Turkey. Phylogenetic analysis supported two separate clades, independent of host or location, suggesting ubiquitous distribution in ticks. JMTV was not recovered from any human, animal or bird specimens tested. Near-complete viral genomes were sequenced from the prototype isolate and from three infected tick pools. Genome topology and functional organization were identical to the members of Jingmen group viruses. Phylogenetic reconstruction of individual viral genome segments and functional elements further supported the close relationship of the strains from Kosovo. We further identified probable recombination events in the JMTV genome, involving closely-related strains from Anatolia or China.


Assuntos
Flaviviridae/classificação , Flaviviridae/genética , Variação Genética , Filogenia , Carrapatos/virologia , Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Animais , China/epidemiologia , Feminino , Flaviviridae/isolamento & purificação , Infecções por Flaviviridae/epidemiologia , Infecções por Flaviviridae/virologia , Genoma Viral , Geografia Médica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Prevalência , Vigilância em Saúde Pública , RNA Viral , Turquia/epidemiologia
12.
Viruses ; 11(8)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374842

RESUMO

We screened ticks and human clinical specimens to detect and characterize tick phleboviruses and pathogenicity in vertebrates. Ticks were collected at locations in Istanbul (Northwest Anatolia, Thrace), Edirne, Kirklareli, and Tekirdag (Thrace), Mersin (Mediterranean Anatolia), Adiyaman and Sanliurfa (Southeastern Anatolia) provinces from 2013-2018 and were analyzed following morphological identification and pooling. Specimens from individuals with febrile disease or meningoencephalitic symptoms of an unknown etiology were also evaluated. The pools were screened via generic tick phlebovirus amplification assays and products were sequenced. Selected pools were used for cell culture and suckling mice inoculations and next generation sequencing (NGS). A total of 7492 ticks were screened in 609 pools where 4.2% were positive. A phylogenetic sequence clustering according to tick species was observed. No human samples were positive. NGS provided near-complete viral replicase coding sequences in three pools. A comprehensive analysis revealed three distinct, monophyletic virus genotypes, comprised of previously-described viruses from Anatolia and the Balkans, with unique fingerprints in conserved amino acid motifs in viral replicase. A novel tick phlebovirus group was discovered circulating in the Balkans and Turkey, with at least three genotypes or species. No evidence for replication in vertebrates or infections in clinical cases could be demonstrated.


Assuntos
Phlebovirus/genética , Carrapatos/virologia , Animais , Chlorocebus aethiops , Genótipo , Humanos , Camundongos , Phlebovirus/classificação , Phlebovirus/isolamento & purificação , Phlebovirus/patogenicidade , Filogenia , RNA Polimerase Dependente de RNA/genética , Turquia , Células Vero , Proteínas Virais/genética
13.
Infect Genet Evol ; 57: 36-45, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29128516

RESUMO

Mosquitoes are involved in the transmission and maintenance of several viral diseases with significant health impact. Biosurveillance efforts have also revealed insect-specific viruses, observed to cocirculate with pathogenic strains. This report describes the findings of flavivirus and rhabdovirus screening, performed in eastern Thrace and Aegean region of Anatolia during 2016, including and expanding on locations with previously-documented virus activity. A mosquito cohort of 1545 individuals comprising 14 species were collected and screened in 108 pools via generic and specific amplification and direct metagenomics by next generation sequencing. Seven mosquito pools (6.4%) were positive in the flavivirus screening. West Nile virus lineage 1 clade 1a sequences were characterized in a pool Culex pipiens sensu lato specimens, providing the initial virus detection in Aegean region following 2010 outbreak. In an Anopheles maculipennis sensu lato pool, sequences closely-related to Anopheles flaviviruses were obtained, with similarities to several African and Australian strains of this new insect-specific flavivirus clade. In pools comprising Uranotaenia unguiculata (n=3), Cx. pipiens s.l. (n=1) and Aedes caspius (n=1) mosquitoes, sequences of a novel flavivirus, distantly-related to Flavivirus AV2011, identified previously in Spain and Turkey, were characterized. Moreover, DNA forms of the novel flavivirus were detected in two Ur. unguiculata pools. These sequences were highly-similar to the sequences amplified from viral RNA, with undisrupted reading frames, suggest the occurrence of viral DNA forms in natural conditions within mosquito hosts. Rhabdovirus screening revealed sequences of a recently-described novel virus, named the Merida-like virus Turkey (MERDLVT) in 5 Cx. pipiens s.l. pools (4.6%). Partial L and N gene sequences of MERDLVT were well-conserved among strains, with evidence for geographical clustering in phylogenetic analyses. Metagenomics provided the near-full genomic sequence in a specimen, revealing an identical genome organization and limited divergence from the prototype MERDLVT isolate.


Assuntos
Culicidae/virologia , Flavivirus/classificação , Flavivirus/genética , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genética , Animais , Sequência de Bases , Flavivirus/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Filogenia , RNA Viral , Proteínas não Estruturais Virais/genética , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação
14.
Parasit Vectors ; 10(1): 149, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28320443

RESUMO

BACKGROUND: Active vector surveillance provides an efficient tool for monitoring the presence or spread of emerging or re-emerging vector-borne viruses. This study was undertaken to investigate the circulation of flaviviruses. Mosquitoes were collected from 58 locations in 10 provinces across the Aegean, Thrace and Mediterranean Anatolian regions of Turkey in 2014 and 2015. Following morphological identification, mosquitoes were pooled and screened by nested and real-time PCR assays. Detected viruses were further characterised by sequencing. Positive pools were inoculated onto cell lines for virus isolation. Next generation sequencing was employed for genomic characterisation of the isolates. RESULTS: A total of 12,711 mosquito specimens representing 15 species were screened in 594 pools. Eleven pools (2%) were reactive in the virus screening assays. Sequencing revealed West Nile virus (WNV) in one Culex pipiens (s.l.) pool from Thrace. WNV sequence corresponded to lineage one clade 1a but clustered distinctly from the Turkish prototype isolate. In 10 pools, insect-specific flaviviruses were characterised as Culex theileri flavivirus in 5 pools of Culex theileri and one pool of Cx. pipiens (s.l.), Ochlerotatus caspius flavivirus in two pools of Aedes (Ochlerotatus) caspius, Flavivirus AV-2011 in one pool of Culiseta annulata, and an undetermined flavivirus in one pool of Uranotaenia unguiculata from the Aegean and Thrace regions. DNA forms or integration of the detected insect-specific flaviviruses were not observed. A virus strain, tentatively named as "Ochlerotatus caspius flavivirus Turkey", was isolated from an Ae. caspius pool in C6/36 cells. The viral genome comprised 10,370 nucleotides with a putative polyprotein of 3,385 amino acids that follows the canonical flavivirus polyprotein organisation. Sequence comparisons and phylogenetic analyses revealed the close relationship of this strain with Ochlerotatus caspius flavivirus from Portugal and Hanko virus from Finland. Several conserved structural and amino acid motifs were identified. CONCLUSIONS: We identified WNV and several distinct insect-specific flaviviruses during an extensive biosurveillance study of mosquitoes in various regions of Turkey in 2014 and 2015. Ongoing circulation of WNV is revealed, with an unprecedented genetic diversity. A probable replicating form of an insect flavivirus identified only in DNA form was detected.


Assuntos
Aedes/virologia , Culex/virologia , Infecções por Flavivirus/virologia , Flavivirus/isolamento & purificação , Insetos Vetores/virologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Aedes/classificação , Animais , Culex/classificação , Flavivirus/classificação , Flavivirus/genética , Flavivirus/fisiologia , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/transmissão , Variação Genética , Genoma Viral , Humanos , Insetos Vetores/classificação , Filogenia , Especificidade da Espécie , Turquia/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/fisiologia
15.
Arch Virol ; 162(7): 1903-1911, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28283817

RESUMO

Next-generation sequencing technologies have significantly facilitated the discovery of novel viruses, and metagenomic surveillance of arthropods has enabled exploration of the diversity of novel or known viral agents. We have identified a novel rhabdovirus that is genetically related to the recently described Merida virus via next-generation sequencing in a mosquito pool from Thrace. The complete viral genome contains 11,798 nucleotides with 83% genome-wide nucleotide sequence similarity to Merida virus. Five major putative open reading frames that follow the canonical rhabdovirus genome organization were identified. A total of 1380 mosquitoes comprising 13 species, collected from Thrace and the Mediterranean and Aegean regions of Anatolia were screened for the novel virus using primers based on the N and L genes of the prototype genome. Eight positive pools (6.2%) exclusively comprised Culex pipiens sensu lato specimens originating from all study regions. Infections were observed in pools with female as well as male or mixed-sex individuals. The overall and Cx. pipiens-specific minimal infection rates were calculated to be 5.7 and 14.8, respectively. Sequencing of the PCR products revealed marked diversity within a portion of the N gene, with up to 4% divergence and distinct amino acid substitutions that were unrelated to the collection site. Phylogenetic analysis of the complete and partial viral polymerase (L gene) amino acid sequences placed the novel virus and Merida virus in a distinct group, indicating that these strains are closely related. The strain is tentatively named "Merida-like virus Turkey". Studies are underway to isolate and further explore the host range and distribution of this new strain.


Assuntos
Culicidae/virologia , Rhabdoviridae/genética , Rhabdoviridae/isolamento & purificação , Animais , Feminino , Genoma Viral , Masculino , Filogenia , Turquia/epidemiologia
16.
Infect Genet Evol ; 46: 138-147, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27840255

RESUMO

Vector surveillance for the arthropod-borne infections has resulted in the isolation of a growing number of novel viruses, including several flavivirus strains that exclusively replicate in insects. This report describes the isolation and genomic characterization of four insect-specific flaviviruses from mosquitoes, previously collected from various locations in Turkey. C6/36 Aedes albopictus and Vero cell lines were inoculated with mosquito pools. On C6/36 cells, mild cytopathic effects, characterized as rounding and detachment, were observed in four pools that comprised female Culex theileri mosquitoes. Complete (3 isolates, 10,697 nucleotides) or near-complete (1 isolate, 10,452 nucleotides) genomic characterization was performed in these culture supernatants via next generation sequencing. All strains demonstrated high genetic similarities, with over 99% identity match on nucleotide and amino acid alignments, revealing them to be different isolates of the same virus. Sequence comparisons identified the closest relative to be the Culex theileri flavivirus (CTFV) strains, originally characterized in Portugal. Phylogenetic analyses demonstrated that the isolates remained distinct as a cluster but formed a monophyletic group with CTFV strains, and shared a common ancestor with Quang Binh or related Culex flaviviruses. The organization of the viral genome was consistent with the universal flavivirus structure and stem-loops; conserved motifs and imperfect tandem repeats were identified in the non-coding ends of the viral genomes. A potential ribosomal shifting site, resulting in the translation of an additional reading frame, was detected. The deduced viral polyprotein comprised 3357 amino acids and was highly-conserved. Amino acid variations, presumably associated with adaptive environmental pressures, were identified. These isolates comprise the first fully characterized insect-specific flaviviruses in Turkey. Their impact on West Nile virus circulation, which is also endemic in the study region, remains to be explored.


Assuntos
Culex/virologia , Flavivirus/genética , Flavivirus/isolamento & purificação , Genoma Viral/genética , Animais , Feminino , Flavivirus/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , RNA Viral/análise , RNA Viral/genética , Análise de Sequência de RNA , Turquia
17.
J Am Acad Dermatol ; 75(2): 393-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26944595

RESUMO

BACKGROUND: Early and complete removal of ticks using the right technique is important to reduce tick-transmitted diseases. Several chemical and mechanical detachment techniques have been described previously. OBJECTIVE: We aimed to compare the performance of 4 tick-detachment techniques that are widely used in human beings and to determine the optimal method from these techniques. METHODS: A cross-sectional study was conducted on 160 patients between April and June 2010. Patients with reported tick bite were reviewed retrospectively and divided into the following 4 groups according to the tick-detachment technique used: card detachment, lassoing, freezing, and tweezers. Performance of each technique was evaluated according to the number of fully detached, nondetached, and crushed ticks and the duration of application. RESULTS: Of the 160 tick-bite cases assessed, we found the following efficacy rates: 82.5% (33/40), technique using tweezers; 47.5% (19/40), lassoing technique; 7.5% (3/40), card detachment; and 0% (0/40), freezing technique. The efficacy rate of the technique using tweezers was significantly higher than that of the other 3 techniques (P < .05). LIMITATIONS: This was a relatively small sample size and not designed as a randomized clinical trial. CONCLUSION: Tick detachment using tweezers, performed in an appropriate manner, is the easiest and most effective technique.


Assuntos
Primeiros Socorros/instrumentação , Picadas de Carrapatos/terapia , Carrapatos , Animais , Estudos Transversais , Humanos , Estudos Retrospectivos
18.
Exp Appl Acarol ; 67(3): 457-66, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26264155

RESUMO

Of 18,667 ticks examined, 33 specimens from species identified as Haemaphysalis parva, Hyalomma marginatum, Hy. scupense, Rhipicephalus bursa and Rh. turanicus were found to have external morphological anomalies. Anomalous Ha. parva, Hy. scupence and Rh. turanicus were reported in this study for the first time. General anomalies manifested as asymmetry and deformations of the idiosoma, whereas local anomalies occurred in legs, exoskeleton, spiracular, adanal, subanal and accessory plates, mouthparts and capitulum. With this study describing a gynandromorphic Hy. marginatum, the number of gynandromorphic tick cases has been raised to two in Turkey.


Assuntos
Ixodidae/anatomia & histologia , Animais , Feminino , Ixodidae/crescimento & desenvolvimento , Masculino , Ninfa/anatomia & histologia , Ninfa/crescimento & desenvolvimento , Turquia
19.
Vector Borne Zoonotic Dis ; 12(11): 938-41, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22925016

RESUMO

A total of 167 ticks collected from humans in Istanbul (Turkey) in 2006 were screened for Rickettsia species, and nested PCRs targeting gltA and ompA rickettsial fragment genes were carried out. Rickettsia monacensis (51), R. aeschlimannii (8), R. conorii subsp. conorii (3), R. helvetica (2), R. raoultii (1), R. africae (1), R. felis (1), and other Rickettsia spp. (2), were detected. To our knowledge, these Rickettsia species (except R. conorii) had never been reported in ticks removed from humans in Turkey. The presence of R. africae also had not been previously described, either in Hyalomma ticks or in any European tick species. In addition, R. aeschlimannii and R. felis had not been found associated with Rhipicephalus bursa specimens. The presence of human pathogenic Rickettsia in ticks removed from humans provides information about the risk of tick-borne rickettsioses in Turkey.


Assuntos
Vetores Aracnídeos/microbiologia , Ixodidae/microbiologia , Infecções por Rickettsia/microbiologia , Rickettsia/isolamento & purificação , Animais , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Citrato (si)-Sintase/genética , Primers do DNA , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genótipo , Humanos , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Rickettsia/genética , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/transmissão , Análise de Sequência de DNA , Picadas de Carrapatos/complicações , Picadas de Carrapatos/epidemiologia , Picadas de Carrapatos/parasitologia , Turquia/epidemiologia
20.
Trop Anim Health Prod ; 44(3): 589-94, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21814751

RESUMO

The presence of Eimeria spp. oocysts in fecal samples collected from 1,108 broiler houses in six regions, representing about 12% of all broiler farms in Turkey, was studied using the modified McMaster method. The age of the chickens in the 1,108 pens varied from 1 to 50 days. Oocysts were found in 602 (54.3%) of these broiler houses, and the mean OPG (oocysts per gram of feces) in those samples was 36,498.7 (50-952,000). No indication of clinical coccidiosis or other clinically evident infection or wide mortality was encountered in any of the pens studied. Further study showed that the age of the chickens, the occurrence of diarrhea on the houses and the density of broiler breeding in the area correlated with subclinical coccidiosis prevalence.


Assuntos
Coccidiose/veterinária , Diarreia/veterinária , Eimeria/fisiologia , Doenças das Aves Domésticas/epidemiologia , Perus , Animais , Infecções Assintomáticas , Coccidiose/epidemiologia , Coccidiose/parasitologia , Diarreia/epidemiologia , Diarreia/parasitologia , Fezes/parasitologia , Oocistos/fisiologia , Doenças das Aves Domésticas/parasitologia , Prevalência , Turquia/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...