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Tick-borne relapsing fever (TBRF) is an acute infectious disease caused by arthropod-borne spirochetes of the genus Borrelia and characterized by recurrent episodes of fever. Borrelia persica, the causative agent of this disease in Israel, is transmitted by the argasid tick Ornithodoros tholozani. There is little information about the maintenance and possible vertebrate reservoirs of B. persica in nature, but the tick O. tholozani is known to feed on animals that enter its habitat in caves, rock crevices and shady environments. The rock hyrax (Procavia capensis) is commonly found in such habitats and may therefore serve as a reservoir host for O. tholozani. Blood and spleen samples from rock hyraxes were collected from twelve locations in Israel and the West Bank during 2009–2014 to test if these animals may be infected with B. persica. Real-time PCR targeting a segment of the flagellin (flaB) gene was initially used to detect B. persica. Positive samples were further analyzed by PCR, using a segment of the glycerophosphodiester phosphodiesterase (GlpQ) gene for additional confirmation. Borrelia species were identified by nucleotide sequence analysis and the copy number of Borrelia was quantified in blood and spleen samples based on the number of Borrelia 16S rRNA gene copies. A total of 112 hyraxes were examined, with both blood and spleen samples tested from 108 animals. Nine hyraxes were infected with B. persica, with a prevalence of 8%. Of these, two animals were positive for both blood and spleen samples, three only for blood and four only for the spleen. The number of DNA copies of Borrelia 16S rRNA was significantly higher in blood (5 × 106 to 9.2 × 108/ml blood) compared to spleen (2.1 × 104 to 1.0 × 106/ml). We conclude that rock hyraxes are possible reservoirs for B. persica because they have long lifespans and gregarious habits, share habitats with vector ticks, and are naturally infected with this spirochete. Further studies should be conducted in the future to evaluate the competence of hyraxes as reservoirs for B. persica infection.

Equine piroplasmosis (EP) is an important tick-borne disease of equids, caused by Theileria equi and Babesia caballi. It is endemic in most parts of the world, including Israel, and has clinical and economic consequences. This study was set to evaluate the presence of EP parasites in domestic donkeys and in wild equids in Israel and the Palestinian Authority (PA). To assess subclinical EP infection in 98 domestic donkeys (Equus africanus asinus), 9 Asiatic wild donkeys (Equus hemionus), 8 zebras (Equus quagga), 7 African wild donkeys (Equus africanus) and 5 mules, were tested using PCR and qPCR. Positive samples were characterized by amplification and sequencing of a 1600 bp fragment of the 18S rRNA gene. Babesia caballi was not detected in any of the animals. Theileria equi was detected in 32% of the donkeys, 89% of Asiatic wild donkeys, 57% of African wild donkeys, 62% of zebras and none of the mules. Parasitemia was low in all of the positive samples. Risk factors associated with infection in donkeys included one farm (Kiryat Gat) and animal sex (male). The sequences of the 18S rRNA gene from domestic donkeys were all similar, and belonged to the T. equi genotype D, similar to the genotype sequenced from horses in the same area, while sequences from wild donkeys were unique and belonged to the T. equi genotype A. Verification of the T. equi genotype in zebras could not be concluded, suggesting major genetic variation.

Hyalomma species (Acari: Ixodidae) are vectors of several human and animal pathogens. However, due to their similar morphological properties, classification of related Hyalomma species is often challenging. Here we describe a combined approach for molecular characterization of six Hyalomma species: H. aegyptium, H. dromedarii, H. excavatum, H. impeltatum, H. marginatum and H. turanicum. This procedure was developed using a combination of PCR amplification of four molecular markers, followed by sequencing and species-specific restriction analysis. Segments from the following genes were used as markers: 12S rRNA, 16S rRNA, Cytochrome C oxidase subunit 1 (COX1), and Cytochrome B (CytB). Phylogenetic analysis based on the amplified sequences was consistent with the morphology-based classification. It revealed relative close proximity of H. excavatum, H. marginatum and H. turanicum, and close proximity of H. aegyptium and H. dromedarii to each other. H. impeltatum was examined using the COX1 and CytB markers, and in both cases was located on a separate clade from the other five species. Digestion of the amplified products using specific restriction enzymes enabled clear distinction between the six species. This report is the first to describe CytB marker sequences of the studied species, and the first to describe COX1 marker sequences of H. aegyptium, H. excavatum, H. impeltatum and H. turanicum. The information obtained in this study may therefore be useful for future combined morphological-molecular Hyalomma characterization.