Theileria orientalis Ikeda in host-seeking Haemaphysalis longicornis in Virginia, U.S.A.

The Asian longhorned tick, Haemaphysalis longicornis, has recently become established in the United States. In East Asia, Australia, and New Zealand, the native and previously introduced ranges, this tick is a vector of an important pathogen of cattle, Theileria orientalis. In 2017, the pathogenic Ikeda genotype of T. orientalis was associated with cattle mortalities in Virginia and in 2018 the exotic H. longicornis was detected at this same site. To investigate the possible role of this exotic tick in the epidemiology of theileriosis in Virginia, we tested host-seeking H. longicornis for piroplasm infections. We document the detection of exotic Theileria orientalis Ikeda genotype in 12.7 % (15/118) environmentally collected H. longicornis using both the 18S rRNA and major piroplasm surface protein (MPSP) gene targets. This is the first detection of a pathogen in H. longicornis in its introduced range in the United States and offers new insight into the animal health risks associated with the introduction of this exotic tick species to North America.

Thompson AT ，White S ，Shaw D ，Egizi A ，Lahmers K ，Ruder MG ，Yabsley MJ ... -  《-》

A U.S. isolate of Theileria orientalis, Ikeda genotype, is transmitted to cattle by the invasive Asian longhorned tick, Haemaphysalis longicornis.

Dinkel KD ，Herndon DR ，Noh SM ，Lahmers KK ，Todd SM ，Ueti MW ，Scoles GA ，Mason KL ，Fry LM ... -  《Parasites & Vectors》

Theileria orientalis Ikeda Genotype in Cattle, Virginia, USA.

Oakes VJ ，Yabsley MJ ，Schwartz D ，LeRoith T ，Bissett C ，Broaddus C ，Schlater JL ，Todd SM ，Boes KM ，Brookhart M ，Lahmers KK ... -  《-》

A multi-seasonal study investigating the phenology, host and habitat associations, and pathogens of Haemaphysalis longicornis in Virginia, U.S.A.

Understanding the abiotic and biotic variables affecting tick populations is essential for studying the biology and health risks associated with vector species. We conducted a study on the phenology of exotic Haemaphysalis longicornis (Asian longhorned tick) at a site in Albemarle County, Virginia, United States. We also assessed the importance of wildlife hosts, habitats, and microclimate variables such as temperature, relative humidity, and wind speed on this exotic tick's presence and abundance. In addition, we determined the prevalence of infection with selected tick-borne pathogens in host-seeking H. longicornis. We determined that the seasonal activity of H. longicornis in Virginia was slightly different from previous studies in the northeastern United States. We observed nymphal ticks persist year-round but were most active in the spring, followed by a peak in adult activity in the summer and larval activity in the fall. We also observed a lower probability of collecting host-seeking H. longicornis in field habitats and the summer months. In addition, we detected H. longicornis on several wildlife hosts, including coyote (Canis latrans), eastern cottontail (Sylvilagus floridanus), raccoon (Procyon lotor), Virginia opossum (Didelphis virginiana), white-tailed deer (Odocoileus virginianus), woodchuck (Marmota monax), and a Peromyscus sp. mouse. This latter record is the first detection of a larval H. longicornis on a North American rodent host important to the enzootic maintenance of tick-borne pathogens of humans and animals. Finally, we continued to detect the exotic piroplasm parasite, Theileria orientalis Ikeda, in H. longicornis as well as other pathogens, including Rickettsia felis, Anaplasma phagocytophilum (AP-1), and a Hepatozoon sp. previously characterized in Amblyomma americanum. These represent some of the first detections of arthropod-borne pathogens native to the United States in host-seeking H. longicornis. These data increase our understanding of H. longicornis biology in the United States and provide valuable information into the future health risks associated with this tick and pathogens.

Thompson AT ，White SA ，Shaw D ，Garrett KB ，Wyckoff ST ，Doub EE ，Ruder MG ，Yabsley MJ ... -  《-》

Multiple piroplasm parasites (Apicomplexa: Piroplasmida) in northeastern populations of the invasive Asian longhorned tick, Haemaphysalis longicornis Neumann (Ixodida: Ixodidae), in the United States.

Herb H ，González J ，Ferreira FC ，Fonseca DM ... -  《-》