Diversity of piroplasms detected in blood-fed and questing ticks from several states in the United States.

Piroplasms in the genera Babesia, Theileria, and Cytauxzoon are tick-borne parasites that may be animal and human pathogens. Most piroplasms with known life cycles are transmitted by ixodid ticks; however, for many species, the vector is unknown. This study was conducted to determine the prevalence and diversity of piroplasms in ticks from several US states. Piroplasm-specific polymerase chain reaction (PCR) assays were used to test 1631 ticks from Georgia (n=486), Kentucky (n=103), Pennsylvania (n=1), Tennessee (n=626), and Texas (n=414). Ticks were either questing (n=42) or collected from animals (n=627) or humans (n=962). The 2 primary species tested were Dermacentor variabilis (n=702) and Amblyomma americanum (n=743), but Amblyomma cajennense (n=99), Amblyomma maculatum (n=16), Ixodes scapularis (n=4), I. woodi (n=1), and unidentified Amblyomma spp. nymphs (n=64) were also tested. A low prevalence of piroplasms was detected with 37 (2.3%), 35 (2.1%), and 9 (0.6%) ticks positive for Theileria spp., Babesia spp., or Cytauxzoon felis, respectively. Based on sequence analysis, at least 6 Babesia spp. were detected and 15 of the 35 (41%) Babesia-positive ticks were A. americanum, 19 (56%) were D. variabilis, and one (3%) was an I. scapularis. Nine Babesia-positive ticks were removed from humans from Kentucky (n=1), Georgia (n=2), Texas (n=5), and Pennsylvania (n=1). Three Babesia-positive ticks were questing A. americanum which represents the first report of Babesia-infected questing Amblyomma in the US. Theileria infections were only detected in A. americanum, and all sequences were similar to white-tailed deer associated Theileria spp. C. felis was only detected in D. variabilis. These data suggest that A. americanum may be a vector of Babesia spp., although experimental studies are needed to confirm vector competence. Finally, these data demonstrate a high diversity of piroplasms in both questing and partially fed ticks in the US; although, host-blood meals can be present in non-questing ticks.

Shock BC ，Moncayo A ，Cohen S ，Mitchell EA ，Williamson PC ，Lopez G ，Garrison LE ，Yabsley MJ ... -  《-》

Endemic, exotic and novel apicomplexan parasites detected during a national study of ticks from companion animals in Australia.

Greay TL ，Zahedi A ，Krige AS ，Owens JM ，Rees RL ，Ryan UM ，Oskam CL ，Irwin PJ ... -  《Parasites & Vectors》

Molecular detection of Theileria spp. and Babesia spp. in sheep and ixodid ticks from the northeast of Iran.

Razmi G ，Pourhosseini M ，Yaghfouri S ，Rashidi A ，Seidabadi M ... -  《-》

Prevalence of tick-borne pathogens in adult Dermacentor spp. ticks from nine collection sites in France.

Bonnet S ，de la Fuente J ，Nicollet P ，Liu X ，Madani N ，Blanchard B ，Maingourd C ，Alongi A ，Torina A ，Fernández de Mera IG ，Vicente J ，George JC ，Vayssier-Taussat M ，Joncour G ... -  《-》

Hepatozoon and Theileria species detected in ticks collected from mammals and snakes in Thailand.

We report the detection of Hepatozoon and Theileria in 103 ticks from mammals and snakes in Thailand. By using a genus-specific 18S rRNA PCR, Hepatozoon and Theileria spp. were detected in 8% and 18%, respectively, of ticks (n=79) removed from mammals. Of the ticks removed from snakes (n=24), 96% were infected with Hepatozoon spp., but none were infected with Theileria. Phylogenetic analysis revealed that Hepatozoon spp. detected from Dermacentor astrosignatus and Dermacentor auratus ticks from Wild boar (Sus scrofa) formed a phylogenetic group with many isolates of Hepatozoon felis that were distantly related to a species group containing Hepatozoon canis and Hepatozoon americanum. In contrast, a phylogenetic analysis of the Hepatozoon sequences of snake ticks revealed that Hepatozoon spp. from Amblyomma varanense from King cobra (Ophiophagus hannah) and Amblyomma helvolum ticks from Indochinese rat snake (Ptyas korros), and Asiatic water snake (Xenochrophis piscator) are grouped with Hepatozoon spp. recently isolated from Monocellate cobras, Reticulated pythons and Burmese pythons, all of Thai origin, and with Hepatozoon sp. 774c that has been detected from a tick species obtained from Argus monitors in Australia. A phylogenetic analysis demonstrated that Theileria spp. from Rhipicephalus (Boophilus) microplus, Haemaphysalis obesa, and Haemaphysalis lagrangei ticks from Sambar deer (Cervus unicolor) cluster with the Theileria cervi isolates WU11 and 239, and Theileria sp. Iwate 141. We report for the first time a Hepatozoon species that shares genetic similarity with Hepatozoon felis found in Dermacentor astrosignatus and Dermacentor auratus ticks collected from Wild boars in Thailand. In addition, we found the presence of a Theileria cervi-like sp. which suggests the potential role of Haemaphysalis lagrangei as a Theileria vector in Thailand.

Sumrandee C ，Baimai V ，Trinachartvanit W ，Ahantarig A ... -  《-》