Genetic analysis of the M RNA segment of Crimean-Congo hemorrhagic fever virus strains in Turkey.

Crimean-Congo hemorrhagic fever (CCHF) virus is member of the genus Nairovirus of the family Bunyaviridae. All members of the family Bunyaviridae 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. During recent years, outbreaks have been reported in Turkey. However, little information is available on the genetic diversity of CCHF virus in Turkey. In this study, a total of 1227 adult ticks were collected from domestic ruminants (796 specimens from cattle, 399 specimens from goats and 32 specimens from sheep). The presence of the M segment of CCHF virus was determined in 4 of 40 (10%) Hyalomma marginatum marginatum pools, in 2 of 38 (7.89%) Rhipicephalus bursa pools, and in 1 of 7 (7%) Boophylus annulatus pools. Hyalomma anatolicum anatolicum pools gave negative RT-PCR result against CCHF virus. Serum samples from seven patients infected with CCHF were selected and subjected to RT-PCR to amplify partial M segment of CCHF virus. This report introduces the first data on partial nucleotide sequences of M RNA segments of CCHF virus strains circulating in Turkey, isolated from ticks.

Detection of Babesia ovis by PCR in Rhipicephalus bursa collected from naturally infested sheep and goats.

Polymerase chain reaction (PCR) was used to assess the presence and the frequency of Babesia ovis infection in the adult Rhipicephalus bursa and their hosts in Elazig province located in eastern Turkey. Tick and blood samples were collected from 32 sheep and 28 goats of four selected herds. A total of 226 R. bursa were randomly selected from the collected ticks and their salivary glands were dissected out in 0.85% saline under stereo microscope. DNA amplification method revealed that the frequency of B. ovis infections in the ticks and the small ruminants were 16.37% (37/226) and 6.66% (4/60), respectively. Three positive products, two of which were from the salivary glands of R. bursa and the other from sheep blood were purified from agarose gel and sequenced. The results showed that nucleotide sequences were identical to the previously reported nucleotide sequences of B. ovis. It is concluded that R. bursa might play an important role in the field as a natural vector of the parasite.

PCR-based detection of Theileria ovis in Rhipicephalus bursa adult ticks.

Tick-borne diseases in ruminants are common in tropical and subtropical regions and lead to meat and milk production losses. In this study, polymerase chain reaction (PCR) was used to assess the presence of Theileria ovis in Rhipicephalus bursa ticks. We have demonstrated that the PCR enabled detection of T. ovis in field isolates of R. bursa collected from naturally infested sheep and goats in eastern Turkey. The sampling was done in spring season (between May and June 2004). A total of 420 R. bursa were collected and randomly selected 192 number of them (97 female and 95 male) were dissected. Primers specific for 520 bp fragments small subunit ribosomal RNA (ssu rRNA) gene of T. ovis amplified products from 37 of the 192 (19.27%) samples. The parasite was detected in 17 (17.52%) female and in 20 (21.05%) male ticks. Two T. ovis amplicons from the tick samples were purified and sequenced. The resulting sequences were identical to the nucleotide sequence of the Turkish sheep strain of T. ovis. These results showed that R. bursa might play an important role in the field as a natural vector of T. ovis.

Development of a polymerase chain reaction method for diagnosis of Babesia ovis infection in sheep and goats.

In this study, a pair of oligonucleotide primers were designed according to the nucleotide sequence of the small subunit ribosomal RNA (ssu rRNA) gene of Babesia ovis isolated from sheep in eastern Turkey. The primers were used to detect parasite DNA from blood samples of B. ovis-infected sheep and goats by polymerase chain reaction (PCR). A 549-bp DNA fragment was specifically amplified from blood samples from sheep and goats, naturally infected with B. ovis. No PCR products resulted from Babesia motasi, T. ovis, Theileria sp. OT1, Theileria sp. OT3, T. lestoquardi, B. canis, B. microti,T. annulata or normal sheep leucocytes DNA using these specific primers. B. ovis-infected erythrocytes with 1% parasitemia were subjected to 10-fold serial dilutions (from 10(-1) to 10(-9)) using an uninfected sheep erythrocytes, and DNA was extracted from each diluted sample for testing the sensitivity of the PCR. The PCR was sensitive enough to detect parasite DNA from the dilution of 10(-5) with 0.00001% parasitemia. This is more sensitive than examining 200 fields under light microscopy. In addition, 98 field samples collected from small ruminanats in eastern Turkey were tested for B. ovis infection. Four samples were positive Babesia spp. in blood smears, 21 samples were positive for B. ovis DNA by PCR. These results indicate that the PCR provides a useful diagnostic tool for the detection of B. ovis infection in sheep and goats.

Prevalence and distribution of tropical theileriosis in eastern Turkey.

This study was carried out to determine the prevalence and distribution of tropical theileriosis in cattle in eastern Turkey by microscopical, serological and molecular methods. A total of 1561 whole blood, 1505 serum and 1483 blood smear samples were collected from cattle of various breeds and ages in 11 towns of Eastern Turkey. Theileria annulata piroplasm DNA extracted from cattle blood was amplified by polymerase chain reaction (PCR) using species-specific primers. Serum antibodies against T. annulata were investigated by indirect fluorescence antibody test (IFAT). Blood smears were examined for Theileria piroplasms by microscopical examination (ME). In the examination of DNA extracted from 1561 blood samples, an amplicon with the size of 721bp was obtained in 37.8% (590/1561) of these samples. Serum antibodies against T. annulata and piroplasm of Theileria spp. were detected in 34.9% (526/1505) and 19.7% (293/1483) of the samples, respectively. The differences between ME and PCR results and between ME and IFAT results were statistically significant (P < 0.05). In contrast, there was no significant difference between the PCR and IFAT results. A total of 179 ticks (136 female; 43 male) belonging to Hyalomma spp. were collected from cattle from three towns. Ticks were identified to be Hyalomma anatolicum anatolicum on the basis of morphological features.

Cattle infestation by Hyalomma ticks and prevalence of Theileria in Hyalomma species in the east of Turkey.

A total of 2388 cattle and 442 shelters, from two provinces (Elazig and Malatya) endemic for tropical theileriosis in the east of Turkey, were studied for Hyalomma tick populations from July 1993 to July 1995 in Elazig and from May 1998 to January 1999 in Malatya. Four thousand five hundred and eighty one of 7455 Hyalomma ticks were collected from cattle, the other ticks (2874) were collected from shelters. All of the ticks collected from shelters were Hyalomma anatolicum anatolicum. Two thousand eight hundred and ninety five (63.1%) of 4581 Hyalomma ticks collected from cattle were H.a. anatolicum. 23.8% (1047/4581), 11.7% (536/4581) and 0.6% (3/4581) of Hyalomma ticks were Hyalomma anatolicum excavatum, Hyalomma detritum and Hyalomma marginatum marginatum, respectively. A total of 5909 Hyalomma adult ticks collected from cattle (3362/5909) and shelters (2447/5909) were dissected and salivary glands were stained with Methylgreen/Pyronin method. Thousand one hundred and fifty (46.9%) of 2447 H.a. anatolicum collected from shelters and 412 (19.1%) of 2147 H.a. anatolicum collected from cattle were positive for Theileria infection. Twenty (2.4%) of 820 H.a. excavatum and 23 (4.6%) of 495 H. detritum collected from cattle were positive. The mean number of infected acini per infected male and female ticks collected from cattle were 11.3 and 22.4 in H.a. anatolicum, 4 and 6.8 in H.a. excavatum, 17.9 and 18.3 in H. detritum, respectively. In H.a. anatolicum collected from shelters, the above rates were 11.8 and 17.6 in male and female ticks, respectively. The prevalence and intensity of Theileria infection was greater in female ticks than in males.