Publications (16)37.3 Total impact
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Article: Pseudo-plaque reduction neutralization test (PPRNT) for the measurement of neutralizing antibodies to Crimean-Congo hemorrhagic fever virus.
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ABSTRACT: BACKGROUND: Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus of the genus Nairovirus family Bunyaviridae, which are enveloped viruses containing tripartite, negative polarity, single-stranded RNA. CCHF is characterized by high case mortality, occurring in Asia, Africa, the Middle East and Europe. Currently, there are no specific treatments or licensed vaccines available for CCHFV. Recently, two research groups have found adult mice with defective interferon responses allowed to lethal CCHFV infection. These mouse models could provide invaluable information for further studies. Efforts to develop a vaccine against CCHFV are being made. To determine the efficacy of vaccine candidates it is important to conduct serological studies that can accurately measure levels of protective antibodies. In the present study, a pseudo-plaque reduction neutralization test (PPRNT) based on enzyme-catalyzed color development of infected cells probed with anti-CCHFV antibodies was used to measure neutralization antibody of CCHFV. METHODS: Sixty-nine human serum samples (20 acute and 49 convalescent) were tested. The presence of CCHFV antibodies was determined and confirmed by a commercial ELISA kit. CCHFV RNA was determined by RT-PCR. All the samples were analyzed by PPRNT and fluorescent focus reduction neutralization test (FFRNT) to measure of CCHFV-neutralizing antibodies. RESULTS: Pseudo-plaque reduction neutralization test showed a high sensitivity (98%), specificity (100%) and agreement (96,6%) in qualitative comparison with those of the FFRNT. There was a high correlation between the titers obtained in PPRNT and FFRNT (R2 = 0.92). The inter- and intra-assay variation of PPRNT revealed good reproducibility and positive cut-off of PPRNT was defined as 1:4 by the geometric mean titers for the individual samples distributed. CONCLUSION: The pseudo-plaque reduction neutralization test described in this study is a fast, reproducible and sensitive method for the measurement of CCHF neutralizing antibodies. This novel assay could serve as useful tools for CCHF research in epidemiology, vaccine development and other studies of immunity. It also provides an alternative to PRNT when viruses with no or poor CPE in cell culture.Virology Journal 01/2013; 10(1):6. · 2.34 Impact Factor -
Article: Application of the pseudo-plaque assay for detection and titration of Crimean-Congo hemorrhagic fever virus.
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ABSTRACT: A pseudo-plaque assay was developed for detection and quantitation of Crimean-Congo hemorrhagic fever virus Turkey-Kelkit06. Enzyme-catalyzed color development of infected cells probed with anti-Crimean-Congo hemorrhagic fever virus antibodies was used for determining the titer of Crimean-Congo hemorrhagic fever Turkey-Kelkit06 and for its detection in samples from persons infected with the Crimean-Congo hemorrhagic fever virus. The pseudo-plaque assay accuracy was confirmed by comparing pseudo-plaque assay titers with fluorescent immunofocus assay and focus formation assay titers using three stocks of virus. No significant difference in virus titers of Crimean-Congo hemorrhagic fever Turkey-Kelkit06 among the three methods was observed. The pseudo-plaque assay is more sensitive than the fluorescent immunofocus assay for detecting the virus in primary isolates of Crimean-Congo hemorrhagic fever virus collected from humans, but no difference in sensitivity between the two methods was observed in the cell-adapted strain of Crimean-Congo hemorrhagic fever Turkey-Kelkit06. The pseudo-plaque assay is suitable for titration of Crimean-Congo hemorrhagic fever Turkey-Kelkit06, which does not develop plaques, suggesting it may also be suitable for the detection of other viruses.Journal of virological methods 08/2012; · 2.13 Impact Factor -
Article: A survey of ixodid ticks feeding on cattle and prevalence of tick-borne pathogens in the Black Sea region of Turkey.
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ABSTRACT: The study reports the frequency of infestation and the prevalence of tick-borne pathogens in feeding adult ticks detached from cattle in two climatic zones of the Black Sea region of Turkey. A total of 2160 adult ticks were collected during 2007-2008. Of these, 1062 were randomly selected, divided into 224 pools, and tested for the presence of bovine Theileria, Babesia, and Anaplasma species. Eleven tick species were recognized on cattle in the study. Hyalomma marginatum was widely disrubuted in the semi-arid bioclimatic zone, but few specimens were collected in the humid bioclimatic zone. The most prevalent tick species in the humid climatic zone was Ixodes ricinus. Infection rates were calculated as the maximum likelihood estimation with 95% confidence intervals (CI). Overall, 4% (CI 2.87-5.44) of 224 tick pools were found to be positive for the pathoges by Reverse line blot. Maximum likelihood estimation of the infection rate varied among tick species, ranging from 2.68% (CI 0.16-12.68) in Haemaphysalis sulcata to 10.49% (CI 4.07-23.66) in Rhipicephalus bursa. The most prevalent tick-borne pathogen was Anaplasma phagocytophilum at 6.78% (CI 3.41-12.18) followed by A. centrale (6.56%, CI 0.42-31.47), Anaplasma/Ehrlichia spp. (3.61%, CI 1.99-6.06), Babesia spp. (3.33%, CI 1.65-6.03), and T. buffeli/orientalis (2.71%, CI 0.73-7.18). Sequencing results indicated that Babesia spp. shared 99% to 100% similarity with the unnamed Babesia sp. Kashi 1 and 2, Babesia sp. Kayseri 1 and Babesia sp.CS58. Anaplasma/Ehrlichia spp. were 98% and 100% identical to Ehrlichia canis and Ehrlichia sp. Omatjenne strain, respectively.Veterinary Parasitology 02/2012; 187(3-4):567-71. · 2.58 Impact Factor -
Article: A study on ovine tick-borne hemoprotozoan parasites (Theileria and Babesia) in the East Black Sea Region of Turkey.
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ABSTRACT: In this study, the frequency of Theileria and Babesia species was assessed via reverse line blotting and blood smear-based diagnostic methods in small ruminants. A total of 201 apparently healthy animals from 26 randomly selected herds located in 4 locations (Artvin, Giresun, Gumushane, and Tokat) of East Black Sea Region of Turkey were investigated for the blood protozoans. In a polymerase chain reaction (PCR), the hypervariable V4 region of the 18S ribosomal RNA gene was amplified with a set of general primers specific for all Theileria and Babesia species. The PCR products were hybridized against catchall and species-specific (Theileria spp., Theileria lestoquardi, Theileria ovis, Theileria sp. OT1, Theileria sp., OT3, Theileria sp., MK, Theileria luwenshuni, Theileria uilenbergi, Babesia spp., Babesia ovis, Babesia motasi, and Babesia crassa) probes. Theileria piroplasms were identified in nine (4.47%) samples by microscopic examination. Reverse line blotting (RLB) detected the infection in 19.90% of the samples. The infection rate of sheep (28.90%) was higher than goats (4.10%). T. ovis, Theileria sp., MK, and Theileria sp. OT3 were detected by RLB. The most prevalent Theileria species was T. ovis (18.90%) followed by Theileria sp. MK (0.99%). Theileria sp. OT3 was detected in one sample (0.43%). A single animal was infected as mix with T. ovis and Theileria sp. MK. The other Theileria (T. lestoquardi, Theileria sp. OT1, T. luwenshuni, and T. uilenbergi) and Babesia (B. ovis, B. motasi, and B. crassa) species were not detected. This study is the first molecular survey on ovine tick-borne protozoans in East Black Sea Region of Turkey.Parasitology Research 01/2012; 111(1):149-53. · 2.15 Impact Factor -
Article: Molecular detection and identification of Anaplasma and Ehrlichia species in cattle from Turkey.
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ABSTRACT: Bovine anaplasmosis is a tick-borne rickettsial disease widespread in tropical and subtropical areas. We investigated the presence and distribution of Anaplasma spp. in cattle from 6 provinces in Turkey. For amplification of the segment spanning the V1 region of the 16S ribosomal RNA (rRNA) gene of Anaplasma species, a reverse line blot (RLB) hybridization assay was performed on 389 blood samples. RLB identified Anaplasma infections in 9.0% (35/389) of the samples. The most frequently found species was A. marginale (11/389, 2.8%), followed by A. centrale (4/389, 1.0%) and A. phagocytophilum (4/389, 1.0%). Eighteen of 35 PCR-positive samples gave positive signals to the catch-all probes, but did not show any response to the species-specific probes tested. Sequencing results of 5 representative amplicons randomly selected from these specimens indicated that 3 were 100% identical to the sequence of A. ovis, and the other 2 sequences were 99.5% identical to the sequence of Ehrlichia sp. Omatjenne strain. The results further confirmed that A. ovis and Ehrlichia sp. Omatjenne infection occurs in cattle populations in Turkey.Ticks and Tick-borne Diseases 03/2011; 2(1):62-5. -
Article: Molecular evidence for Anaplasma phagocytophilum in Ixodes ricinus from Turkey.
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ABSTRACT: This study investigated the presence of the pathogen Anaplasma phagocytophilum in ixodid ticks removed from humans living in three provinces (Giresun, Trabzon, Rize) in the east of the Black Sea Region of Turkey. A total of 1097 ixodid ticks were examined for the presence of A. phagocytophilum DNA. From the 95 pooled tick samples tested, species-specific fragments of A. phagocytophilum (11/95 samples, 11.6%) were amplified by nested PCR. Adult Ixodes ricinus (9/53 samples, 17.0%) and Ixodes spp. nymphs (2/9 samples, 22.2%) were infected with A. phagocytophilum. None of the remaining tick species gave a positive result for the presence of the pathogen. All nested PCR-positive samples were directly sequenced. The partial sequences (457bp) of the amplicons obtained from the infected tick pools were 100% identical to one another and to previously isolated sequences from human patients. To obtain a longer 16S rRNA gene sequence, one representative sample was reamplified with the universal primer set. The longer representative sequence (1306bp) also shared 99.92% similarity (a single adenine deletion) with the recently reported complete sequence of A. phagocytophilum.Transactions of the Royal Society of Tropical Medicine and Hygiene 10/2009; 104(1):10-5. · 2.16 Impact Factor -
Article: Molecular detection and identification of Ehrlichia and Anaplasma species in ixodid ticks.
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ABSTRACT: A polymerase chain reaction (PCR) assay followed by partial sequencing of the 16S ribosomal RNA gene was performed for the presence of Ehrlichia and/or Anaplasma. A total of 242 ixodid ticks were collected from domestic ruminants and their shelters, as well as humans, and their individual salivary glands were dissected out for DNA. From the 242 ticks analyzed, six (2.47%), comprising three Hyalomma anatolicum anatolicum, one Rhipicephalus bursa, and two Rhipicephalus sanguineus, were positive. Of these sequenced samples directly obtained from the PCR products, three sequences from H. a. anatolicum were identical to that of the gene of Ehrlichia spp. strains. One sequence identified in R. bursa was closely related to Anaplasma platys. The remaining two sequences detected in R. sanguineus were similar to that of the gene of Anaplasma ovis. The study presented here provides preliminary data regarding the presence of rickettsial pathogens in ticks in Turkey.Parasitology Research 03/2009; 104(5):1243-8. · 2.15 Impact Factor -
Article: Molecular detection of Theileria and Babesia infections in cattle.
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ABSTRACT: This study was carried out to determine the presence and distribution of tick-borne haemoprotozoan parasites (Theileria and Babesia) in apparently healthy cattle in the East Black Sea Region of Turkey. A total of 389 blood samples were collected from the animals of various ages in six provinces in the region. Prevalence of infection was determined by reverse line blot (RLB) assay. The hypervariable V4 region of the 18S ribosomal RNA (rRNA) gene was amplified with a set of primers for members of the genera Theileria and Babesia. Amplified PCR products were hybridized onto a membrane to which generic- and species-specific oligonucleotide probes were covalently linked. RLB hybridization identified infection in 16.19% of the samples. Blood smears were also examined microscopically for Theileria and/or Babesia spp. and 5.14% were positive. All samples shown to be positive by microscopy also tested positive with RLB assay. Two Theileria (T. annulata and T. buffeli/orientalis) and three Babesia (B. bigemina, B. major and Babesia sp.) species or genotypes were identified in the region. Babesia sp. genotype shared 99% similarity with the previously reported sequences of Babesia sp. Kashi 1, Babesia sp. Kashi 2 and Babesia sp. Kayseri 1. The most frequently found species was T. buffeli/orientalis, present in 11.56% of the samples. T. annulata was identified in five samples (1.28%). Babesia infections were less frequently detected: B. bigemina was found in three samples (0.77%), B. major in two samples (0.51%) and Babesia sp. in five samples (1.28%). A single animal infected with T. buffeli/orientalis was also infected with B. bigemina.Veterinary Parasitology 11/2008; 158(4):295-301. · 2.58 Impact Factor -
Article: Evaluation of a PCR and comparison with RLB for detection and differentiation of Theileria sp. MK and other Theileria and Babesia species of small ruminants.
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ABSTRACT: Theileria sp. MK in sheep and goats were detected first time by polymerase chain reaction (PCR) and detection limit of PCR and reverse line blotting (RLB) were compared. A part of 18S ssu rRNA gene was amplified from blood samples that were taken from sheep and goats naturally infected with Theileria sp. MK by PCR. Detection limit of both PCR and RLB methods was one infected cell in 10(7) sheep erythrocytes. Nine hundred twenty field samples that had been tested previously by RLB were evaluated by the PCR assay. As found by RLB previously, 12 of 920 (1.30%) samples were detected as positive by PCR. Two positive PCR products, one of which was from sheep and the other from goat, were sequenced. These sequences were identical to the reported nucleotide sequence of Theileria sp. MK. It is concluded that the PCR described in this study will be useful for epidemiological studies and for discrimination between Theileria sp. MK and other Theileria species. In addition, PCR has superiority over RLB because of its ease of use and time period required.Parasitology Research 08/2008; 103(2):319-23. · 2.15 Impact Factor -
Article: Molecular identification, genetic diversity and distribution of Theileria and Babesia species infecting small ruminants.
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ABSTRACT: Detection and identification of Theileria and Babesia species in 920 apparently healthy small ruminants in eastern Turkey, as well as parasite genetic diversity, was investigated using a specifically designed reverse line blot (RLB) assay. The hypervariable V4 region of the 18S ribosomal RNA (rRNA) gene was amplified and hybridized to a membrane onto which catchall and species-specific oligonucleotide probes were covalently linked. Three Theileria and one Babesia genotype were identified. Comparison of the Theileria genotypes revealed 93.6-96.2% similarity among their 18S rRNA genes. Two Theileria shared 100% and 99.7% similarity with the previously described sequences of T. ovis and Theileria sp. OT3, respectively. A third Theileria genotype was found to be clearly different from previously described Theileria species. The genotype was provisionally designated as Theileria sp. MK. The Babesia genotype shared 100% similarity with Babesia ovis. The survey indicated a high prevalence of piroplasm infections in small ruminants (38.36%). Theileria spp. prevalence was 36.08%. Prevalence of B. ovis was 5.43%. The most abundant Theileria species identified was T. ovis (34.56%) followed by Theileia sp. MK (1.30%) and Theileria sp. OT3 (0.43%).Veterinary Parasitology 07/2007; 147(1-2):161-5. · 2.58 Impact Factor -
Article: Comparison and phylogenetic analysis of the heat shock protein 70 gene of Babesia parasites from dogs.
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ABSTRACT: The heat shock protein 70 (hsp70) genes of Babesia gibsoni, B. canis canis, B. canis vogeli, and B. canis rossi isolated from infected dogs were cloned by polymerase chain reaction (PCR) and sequenced. In the nucleotide sequence and the predicted amino acid sequence of the gene, the parasites were very similar to each other. The nucleotide sequences of the hsp70 gene had more variety than those of 18S nuclear subunit ribosomal DNA (18S rDNA). A phylogenetic analysis of these sequences and comparisons with sequences from other Babesia and Theileria species revealed that all canine babesial isolates analyzed in the present study were closely related to each other and formed one cluster. Additionally, a phylogenetic analysis of Babesia and Theileria species showed that these parasites could be divided into three groups: group A including canine babesial isolates, B. divergens, B. odocoilei, B. bovis, B. caballi, and B. ovis; group B including Theileria annulata, T. orientalis, and T. cervi; and group C including B. microti and B. rodhaini. These results suggested that a phylogenetic analysis of the hsp70 gene sequence might be helpful in classifying Babesia and Theileria species, and that canine babesial isolates might be closely related to each other, indicating their evolution from the same ancestry.Veterinary Parasitology 05/2007; 145(3-4):217-27. · 2.58 Impact Factor -
Article: Determination of prevalence and risk factors for infection with Babesia ovis in small ruminants from Turkey by polymerase chain reaction.
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ABSTRACT: In this study, PCR and thin blood smear-based diagnostic methods were used to assess the frequency of Babesia infection in small ruminants. A total of 300 sheep and 100 goats from 37 randomly selected herds located in eight locations of eastern Turkey were examined for the presence of Babesia infection and any tick species on the body of the animals. Of 400 blood samples examined, 6 (1.5%) were positive for Babesia spp. piroplasms upon microscopic examination, whereas 33 (8.25%) were positive for the presence of B. ovis by PCR. The prevalence of babesiosis in small ruminants detected by PCR was significantly higher than obtained in microscopic examination of thin blood smears (P < 0.05). Thirty-three animals produced the DNA fragment specific for Babesia ovis of which 32 (10.66%) were sheep and 1 (1%) was goat. The difference between the prevalence of Babesia infection in sheep and goats were statistically significant (P < 0.05). The prevalence of Babesia infection in different age groups of sheep were statistically non-significant (P > 0.05). The frequency of B. ovis infection was higher in herds with tick burden than no tick burden (P < 0.05). Seven amplicons (six from sheep and one from goat) were sequenced. The resulting sequences were identical to the recently reported nucleotide sequence of B. ovis. A total of 510 ticks belonging to the Rhipicephalus spp. were collected from sheep. Ticks were identified to be R. bursa and R. turanicus on the basis of morphological features.Parasitology Research 04/2007; 100(4):797-802. · 2.15 Impact Factor -
Article: Modeling the spatial distribution of crimean-congo hemorrhagic fever outbreaks in Turkey.
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ABSTRACT: The more than 1100 human cases of Crimean-Congo Hemorrhagic Fever (CCHF) reported in a continuing series of outbreaks that started in 2003 in Turkey constitute the largest epidemic of the disease since CCHF was first recognized in 1944. The spatial distribution of CCHF case reporting rates in Turkey was studied to look for clusters of disease. We applied the spatial scan analysis to test the hypothesis of whether there were areas with a higher than expected number of CCHF cases. The analysis was conducted through windows of 10, 20, 40 and 80 km in diameter[SR1] to determine whether clustering of cases was dependent on the size of the scanning window. At the largest window size, consistent patterns of significantly higher than expected numbers of CCHF cases were found in a total of 40 administrative districts. A predictive model to map the habitat suitability for the vector tick was developed from satellite-based climate data and high-resolution features of the vegetation from Landsat images covering the whole country. It was found that areas of higher risk (higher CCHF reporting) were correlated (p<0.05) with zones of high climate suitability for the tick together with a high rate of fragmentation of agricultural land interspersed between forest and shrub-type vegetation.Vector Borne and Zoonotic Diseases 02/2007; 7(4):667-78. · 2.44 Impact Factor -
Article: Crimean-Congo hemorrhagic fever virus: genetic analysis and tick survey in Turkey.
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ABSTRACT: Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus in the family Bunyaviridae, genus Nairovirus. The virus is transmitted to humans through infected tick bites or from direct contact with viremic animals or humans. In the present study, a total of 1,015 adult ticks were collected from cattle (603 specimens), sheep (17 specimens), and goats (395 specimens) in the Kelkit Valley in Turkey. Four tick species were recognized on the animals in the surveyed region. The most abundant species were Rhipicephalus bursa and Hyalomma marginatum marginatum, at 47.68% (484/1,015) and 46.40% (471/1,015), respectively. Reverse transcriptase PCR was used to recover partial sequences of the CCHFV small (S) genome segment. The presence of CCHFV was determined in 3 of 33 (9.09%) R. bursa pools and in 1 of 31 (3.22%) H. m. marginatum pools. Virus sequences from R. bursa were extremely different from those of the Greek CCHFV strain (U04958) isolated from an R. bursa tick. Phylogenetic analysis indicated that the CCHFV isolates obtained in this study clustered in group 5, whose range encompasses southwestern Russian and Kosovo. This is the first evidence of CCHFV in ticks from Turkey. Even though Hyalomma is the main vector for CCHFV, R. bursa may play a role in CCHFV transmission.Journal of Clinical Microbiology 12/2006; 44(11):4120-4. · 4.15 Impact Factor -
Article: A molecular survey of bovine Theileria parasites among apparently healthy cattle and with a note on the distribution of ticks in eastern Turkey.
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ABSTRACT: A survey of Theileria parasites in cattle in eastern Turkey was carried out using specific polymerase chain reaction. A total of 252 blood samples were collected from clinically healthy cattle between June and July 2004. Of 252 blood samples examined, 41 (16%) were positive for piroplasms by microscopy, whereas 114 (45%) were positive for the presence of at least one species of Theileria by PCR. The percentages of positive animals for Theileria annulata and benign Theileria species (Theileria sergenti/buffeli/orientalis) were 39% (99/252) and 7% (18/252), respectively. By allele-specific PCR examination of 18 field isolates which were positive for benign Theileria parasites, 8 samples were only amplified by B-type specific primers and 10 samples were amplified by both of the B and C-type specific primers, indicating a mixed infection with B and C-type of the parasite. None of the field isolates was amplified by I-type specific primers. Three samples were co-infected with T. annulata and benign Theileria parasites. Two of them which were infected with B-type parasite were also infected with T. annulata, the other sample which was infected both of B and C-type parasites was also infected with T. annulata. A total of 724 ixodid ticks were collected from the cattle. Hyalomma anatolicum anatolicum was the dominant species with 32% (230/724) in the region. H. a. excavatum, Boophylus annulatus and Rhipicephalus bursa represented 25% (183/724), 19% (140/724) and 15% (112/724) of the total number of ticks, respectively. R. sanguineus was the minor species and represented 8% (59/724) of the tick population.Veterinary Parasitology 07/2006; 138(3-4):179-85. · 2.58 Impact Factor -
Article: Detection of Theileria ovis in naturally infected sheep by nested PCR.
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ABSTRACT: A nested polymerase chain reaction (PCR) for the detection of Theileria ovis in sheep using oligonucleotide primers designed from the small subunit ribosomal RNA (SSU rRNA) gene sequence of T. ovis from sheep in eastern Turkey is described. A 398-bp DNA fragment was specifically amplified from blood samples from sheep, naturally infected with T. ovis. No PCR products resulted from T. lestoquardi, T. annulata, T. parva, T. buffeli and Babesia spp. DNA using these specific primers. The sensitivity of the nested PCR for T. ovis, which was assessed showed that one infected cell in 10(7) sheep erythrocytes, equivalent to a blood parasitemia of 0.00001%, could be detected. This is more sensitive than examining 200 fields under light microscopy. In addition, of the 124 field samples obtained from sheep in eastern Turkey tested, 19.35% (24/124) were positive for the presence of Theileria spp. by microscopic examination compared to 54.03% (67/124) positive for T. ovis by nested PCR. The primer pairs described in this study will be useful for epidemiological studies on ovine theileriosis and for discrimination between T. lestoquardi and T. ovis infections in sheep.Veterinary Parasitology 02/2005; 127(2):99-104. · 2.58 Impact Factor
Top co-authors
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Institutions
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2012
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Cumhuriyet University
Sivas, Sivas, Turkey
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2005–2012
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Firat University
- Department of Parasitology
Elazığ, Elazig, Turkey
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