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Ixodid ticks transmit various infectious agents that cause disease in humans and livestock worldwide. A cross-sectional survey on the presence of protozoan pathogens in ticks was carried out to assess the impact of tick-borne protozoa on domestic animals in Palestine. Ticks were collected from herds with sheep, goats and dogs in different geographic districts and their species were determined using morphological keys. The presence of piroplasms and Hepatozoon spp. was determined by PCR amplification of a 460-540bp fragment of the 18S rRNA gene followed by RFLP or DNA sequencing. A PCR-RFLP method based on the 18S rRNA was used in order to detect and to identify Hepatozoon, Babesia and Theileria spp. A total of 516 ticks were collected from animals in six Palestinian localities. Five tick species were found: Rhipicephalus sanguineus sensu lato, Rhipicephalus turanicus, Rhipicephalus bursa, Haemaphysalis parva and Haemaphysalis adleri. PCR-based analyses of the ticks revealed Theileria ovis (5.4%), Hepatozoon canis (4.3%), Babesia ovis (0.6%), and Babesia vogeli (0.4%). Theileria ovis was significantly associated with ticks from sheep and with R. turanicus ticks (p<0.01). H. canis was detected only in R. sanguineus s.l. and was significantly associated with ticks from dogs (p<0.01). To our knowledge, this is the first report describing the presence of these pathogens in ticks collected from Palestine. Communicating these findings with health and veterinary professionals will increase their awareness, and contribute to improved diagnosis and treatment of tick-borne diseases., (Copyright © 2016. Published by Elsevier GmbH.)

Leishmania tropica is the causative agent of zoonotic cutaneous leishmaniasis in different parts of the Old World. Although it is a common cause of disease in some areas of the world, there is insufficient knowledge on the pathogenicity of this parasite in mammalian hosts and animal models. L. tropica luciferase-transfected metacyclic-stage promastigotes were inoculated into the footpad or ear of Sprague Dawley (SD) rats. Parasite DNA was detected by kDNA real time PCR in the blood at varying levels from 2 days to 5 weeks post infection (PI) in the absence of clinical signs. Parasite DNA was found in the spleen of all rats at the end of the study, and the parasitic load was up to 40 times higher in the spleen when compared with inoculation sites. Parasites were cultured from the spleen, and skin inoculation sites 5 weeks PI. Bioluminescent parasites were observed by in vivo imaging at one day PI, but the technique was not sufficiently sensitive to follow parasite spread after this time. This study provides new evidence for the viscerotropic spread of L. tropica in the rat and demonstrates that the rat can serve as a model for persistent visceralizing infection with this parasite., (Copyright © 2012 Elsevier B.V. All rights reserved.)

An outbreak of trypanosomoasis caused by Trypanosoma evansi involving horses, camels and donkeys occurred in a farm in Israel. A longitudinal study of two outbreak phases was conducted which included clinical monitoring, blood smears, packed cell volume (PCV), serology and polymerase chain reaction (PCR) followed by reverse dot blot (RDB) for the molecular detection of infection. This was the first reported T. evansi outbreak in domestic animals in Israel. Most of the camels on the farm (8/10; 80%) were diagnosed with T. evansi infection whereas infection was less prevalent in the horses (3/7; 43%) and donkeys (6/13; 46%). Clinical disease was evident in 4 camels and 1 horse exhibiting characteristic clinical signs, anemia and parasitemia detected on blood smears and by positive RDB. Six other animals were diagnosed as asymptomatic latent carriers by positive RDB and 6 additional animals were only seropositive and were considered suspected carriers. A significant difference was found in the mean PCV between symptomatic and latent carriers with severe anemia observed only in the symptomatic animals. An anaphylactic-like reaction, fatal in one case, was observed in 2 camels diagnosed with severe trypanosome parasitemia immediately following treatment with melarsenoxide cysteamine. Furthermore, recurrence of infection was documented in one camel 4 months post treatment., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Optimum conditions for generating Leishmania (Leishmania) tropica axenic amastigotes (AxA) in culture were determined, pH 5.5/36 degrees C, and the parasites characterized by different techniques, including light microscopy, macrophage infection, stage specific antigen expression and differential display. AxA were morphologically similar to amastigotes and 15.5-fold more infective than stationary phase promastigotes for mouse peritoneal macrophages. Western blotting with promastigote stage specific monoclonal antibodies to either lipophosphoglycan (T2) or a 60 kDa flagella antigen (F3) showed a dramatic decrease in antigen expression when AxA were compared to promastigotes. Similarly F3 gave strong immune fluorescent staining of the promastigote flagellum, but no fluorescence was detected when AxA were examined. Conversely, Western blotting with the amastigote specific monoclonal antibody (T16) showed that this antigen is more highly expressed in AxA than promastigotes. Differential display-PCR was used to identify several parasite genes showing stage specific expression. One gene selectively expressed by AxA was partially sequenced and identified as Leishmania (L.) tropicaamastin. Amastigote specific expression of this gene was further confirmed by reverse transcriptase-PCR (RT-PCR) using AxA and infected macrophages. No amastin expression was observed with promastigotes. Expression of the cysteine protease B (cpb) and protein kinase A catalytic isoform 1 subunit (pkac1) in promastigotes and AxA was also examined by RT-PCR. Pkac1 was strongly expressed by promastigotes, while cpb expression was only seen with AxA or infected macrophages. L. (L.) tropica AxA will prove useful for further studies on parasite differentiation and gene regulation, as well as for drug screening.

Leishmania infantum is the causative agent of canine and human visceral leishmaniasis in Israel and Palestine. Amplification of the kinetoplast DNA (kDNA), followed by restriction fragment length polymorphism (RFLP) analysis with restriction enzymes was used to examine the genotypic association between L. infantum strains isolated from 22 dogs and 2 humans from these adjoining regions. Results showed wide kDNA heterogeneity in these strains. Two main clusters (A and B) were identified. Cluster A was restricted to central Israel and was mainly found in strains isolated after 2002 whereas cluster B included parasites from central Israel and the West Bank. The kDNA microheterogeneity in L. infantum parasite populations as shown by genotyping with the kDNA-PCR and RFLP provided a tool to study the epidemiology of the disease and track its spread in central Israel and Palestine.

Multilocus microsatellite typing (MLMT) was used to investigate the genetic variation among 44 Israeli and Palestinian strains of L. infantum isolated from infected dogs and human cases to determine their population structure and to compare them with strains isolated from different European countries. Most of the Israeli and Palestinian strains had their own individual MLMT profiles; a few shared the same profile. A Bayesian model-based approach and phylogenetic reconstructions based on genetic distances inferred two main populations that were significantly different from the European strains: population A, containing 16 strains from places in the West Bank and 11 strains from central Israel;and population B, containing 7 strains from northern Israel, 9 from central Israel, and one Palestinian strain from the Jenin District.Geographically distributed sub-populations were detected within population B. These results demonstrate similar disease dynamics in Israel and the Palestinian Authority. The re-emergence of VL in the case of population A is more likely owing to increased dog and human contact with sylvatic cycles of parasitic infection rather than to recent introduction from the older foci of northern Israel. The latter scenario could be true for population B found in few foci of Central Israel., ((c) 2009 Elsevier Masson SAS. All rights reserved.)

Visceral leishmaniasis caused by Leishmania infantum is an endemic zoonosis, present in the Mediterranean area and well recognized in Israel and Palestine for human and dog disease. A serological study using an ELISA technique was performed on 104 cats living in the Jerusalem area. Seroprevalence was 6.7% (7/104). Significant correlation between seropositive cat results and altitude > 2500 ft was observed (p = 0.02). This is the first serological survey of feline leishmaniasis (FL) in the Middle East. To prove cat involvement as a secondary host, more investigations are still needed. The study concludes that cat involvement in Leishmania host studies should not be ignored.