Babesia negevi infection in dogs and response to treatment.

Canine babesiosis is an important protozoan tick-borne disease associated with anemia and thrombocytopenia and caused by several different Babesia spp. Babesia negevi was first reported to infect dogs in the Middle East in 2020. This study describes the presentation, clinical signs, parasitemia levels quantified by molecular techniques, laboratory findings and treatment of dogs infected with B. negevi following the first description of this species. Clinical findings in the infected dogs, a 3-year old female and two 8-week old male and female pups, included extreme lethargy and pale mucous membranes, anemia and thrombocytopenia found in all three animals. Fever was present in the older female and icterus in the female pup. Babesia parasites resembling B. negevi were detected by microscopy of blood smears from the dogs. PCR of blood targeting the 18S rRNA and cox1 genes confirmed that babesiosis was caused by B. negevi and PCR targeting the Borrelia flagellin gene indicated co-infection with Borrelia persica in two dogs. Treatment of the dogs with imidocarb dipropionate resulted in clinical improvement and initial decrease in the B. negevi parasite load as detected by quantitative PCR in two dogs, however the female pup continued to deteriorate and died. The parasite load in the 3-year old female decreased from 43,451 parasites/µl blood pre-imidocarb dipropionate treatment to 803 parasites/µl within two weeks. In the surviving pup, it decreased from 3,293,538 parasites/µl pre-treatment to 20,092 parasites/µl after two weeks. Babesia negevi DNA was still recovered from blood samples by PCR despite repeated treatment with imidocarb dipropionate one-month post-treatment in the surviving pup and up to seven months post-treatment in the 3-year old female. Only treatment with atovaquone and azithromycin for ten days eliminated B. negevi in both dogs as confirmed by negative PCR two weeks later. In conclusion, treatment with imidocarb dipropionate was helpful for recovery from clinical disease but did not facilitate parasite elimination, and it is therefore recommended to treat canine B. negevi infection with the combination of atovaquone and azithromycin.

Seroprevalence and risk factor analysis for exposure to equine encephalosis virus in Israel, Palestine and Jordan.

Equine encephalosis virus (EEV) is an orbivirus transmitted by Culicoides species. Most infected horses show mild clinical signs and mortality is usually very low. EEV is closely related and similarly transmitted to other, more pathogenic and economically important, orbiviruses such as African horse sickness virus (AHSV), bluetongue virus (BTV) and epizootic haemorrhagic disease viruses (EHDV), and may serve as an indicator for possible transmission of the latter. Israel has been reported to be endemic for EEV since 2001. This study was initiated to re-evaluate the current seroprevalence and risk factors for EEV exposure in Israel, and to assess, for the first time, the seroprevalence of EEV in Palestine and Jordan. Three hundred and sixteen serum samples were collected from apparently healthy horses at 21 farms in Israel, 66 horses at nine farms in Palestine and 100 horses at three farms in Jordan. The presence of EEV antibodies was detected by a serum neutralization assay. Seroprevalence of EEV was 58.2% (184/316 horses) in Israel, 48.5% (32/66 horses) in Palestine and 2% (2/100 horses) in Jordan. Seroprevalence in Jordan was significantly lower than in Israel and Palestine (P < 0.001). The farm (P < 0.001) and horse age (P = 0.003) were found as significant risk factors for EEV exposure in Israel in multivariable statistical analysis. The results of this study further demonstrate that EEV is no longer limited to South Africa and is endemic in both Israel and Palestine and horses in Jordan were also exposed to this virus emphasizing the potential of pathogens to invade new ecological niches.

Characterization of Theileria equi genotypes in horses in Israel, the Palestinian Authority and Jordan.

Equine theileriosis caused by Theileria equi is endemic in the Middle East, where it causes a severe disease as well as widespread subclinical infection. The aim of this study was to evaluate the diversity of T. equi genotypes in Israel and the neighboring Palestinian Authority and Jordan. Blood samples from 355 horses from Israel, the Palestinian Authority and Jordan were tested for the prevalence of T. equi DNA. Two hundred and fourteen (60%) were found positive for T. equi infection by PCR. Of those, the 18S rRNA (1458bp) and the EMA-1 (745bp) genes of T. equi were sequenced from 15 horse samples that represent Israel's geographical distribution together with four samples from the Palestinian Authority and two from Jordan. The results were used for genotype characterization and phylogenetic analysis of T. equi in the equine population in Israel and its surroundings. Three 18S rRNA genotype clades were found in Israel (A, C and D) with clade D being the most prevalent and included all four isolates from the PA. In contrast, the EMA-1 gene showed little diversity with all sequences clustering in the same clade apart from one Jordanian sequence. Results suggest that although the Israeli horse population is small and relatively confined geographically, it is probable that the genetic variability, which was found among Israeli horses, is a result of introduction of horses from other countries. It also suggests that the EMA-1 gene is probably not a good target for the evaluation of variance in T. equi populations. Characterization of the different genotypes prevalent in a certain region is important in order to map out the intra-species sequence heterogeneity of the parasite, which is needed in order to develop new diagnostic tools and vaccines.

Novel description of force of infection and risk factors associated with Theileria equi in horses in Israel and in The Palestinian Authority.

The objectives of this study were to determine the force of infection (FOI) for Theileria equi in horses in Israel and to evaluate risk factors associated with seroprevalence a decade after it was last determined by PCR, in 2002. Using a commercial cELISA kit, we demonstrated a widespread and constant exposure to T. equi in Israel (110/216; 50.9%) and the Palestinian Authority (32/108; 29.6%). Owing to the paired samples collected from the same horses approximately one year apart, we were able to determine the FOI rate with which susceptible individuals become infected. Out of the 75 naïve horses in the first collection, four seroconverted during 10-16 months, demonstrating an FOI of 5% for that period. Similar results were obtained by calculating FOI using age-specific seroprevalence (4.2% per year). Housing management type was significantly associated with T. equi seroprevalence with 87.9% seropositivity in horses on pasture and 32.6% seropositivity in horses in stalls/yards. This strong association and the very high seroprevalence found in horses held on pasture, prompted stratification of data accordingly. Geographical location of horses in Israel showed a strong association with seroprevalence to T. equi ranging from 34.5% in central Israel to 80.8% in the northern part of the country. However, when analyzing this association only in horses held in stalls/yards, the lower seroprevalence was noted in the north. In addition, age was significantly associated with seroprevalence for T. equi only in horses held in stalls/yards (R(2)=0.94). Environmental variables were not found to be associated with seroprevalence for T. equi. Here, we report for the first time the FOI for T. equi in horses and highlight the influence housing management type has on the evaluation of risk factors associated with a vector-borne disease, perhaps leading to the discrepancies observed between studies throughout the world.

Mucocutaneous Leishmania tropica infection in a dog from a human cutaneous leishmaniasis focus.

BACKGROUND: Leishmania tropica is a causative agent of cutaneous leishmanaisis in the Middle East, North Africa and parts of southeastern Europe. Although transmission of L. tropica has been reported as anthroponotic, in Israel it was found to have a zoonotic pattern. FINDINGS: A one year old male Pekingese dog from Maale Adumim, a focus of L. tropica human cutaneous leishmaniasis near Jerusalem, was presented by its owner with a large proliferative red mucocutaneous lesion on the lip between the mouth and nose. Physical examination and a biochemistry panel were normal and a complete blood count showed mild leukocytosis with lymphocytosis and eosinophilia. A biopsy of the lesion was suggestive of the presence of Leishmania organisms. Serology for Leishmania sp. by ELISA was positive and an aspirate from the lesion showed a large number of Leishmania amastigotes. ITS1-HRM-PCR of the lesion was positive and sequencing indicated that infection was caused by L. tropica, which was also cultured from the lesion. Blood PCR was negative. The dog responded well to allopurinol treatment and its lesion shrunk considerably within one month of therapy and healed after two months. CONCLUSIONS: Only a few cases of dog infection with L. tropica have been described to date. They were reported from Morocco and Iran and involved infection of visceral organs. This is the first report of focal mucocutaneous L. tropica infection in a dog and its response to anti-leishmanial treatment. Domestic and wild canines should be evaluated for being possible animal reservoirs for human L. tropica infection in endemic areas or merely accidental hosts.

Outbreak of subclinical mastitis in a flock of dairy goats associated with atypical Staphylococcus haemolyticus.

Staphylococcus haemolyticus is a pathogen frequently isolated from dairy cows and small ruminants. However, it always appears in only a few animals and not as a major pathogen. Recently, in a dairy goat herd of approximately 250 milking animals, 25.6% (46/180 goats) had milk cultures with atypical highly mucoid colonies accompanied by elevated somatic cell counts. The isolates were identified as Staph. haemolyticus. The present study describes the steps used in an attempt to identify the bacterium and to compare it with other coagulase-negative staphylococci (CNS) including Staph. haemolyticus. Species identification performed with the API STAPH-IDENT 32 kit showed >99.4% identity confirmed by 16S rDNA sequencing tests. Microscopically the atypical Staph. haemolyticus strains showed unique cuboidal tetrad clusters reminiscent of those of the genus Sarcina. The outbreak caused by an atypical CNS underlines the need for accurate biochemical and genetic methods for ultimate identification of CNS to the species level.