In vitro isolation and cultivation of a Babesia from an American woodland caribou (Rangifer tarandus caribou)

The Contribution of Wildlife Hosts to the Rise of Ticks and Tick-Borne Diseases in North America

Wildlife vertebrate hosts are integral to enzootic cycles of tick-borne pathogens, and in some cases have played key roles in the recent rise of ticks and tick-borne diseases in North America. In this forum article, we highlight roles that wildlife hosts play in the maintenance and transmission of zoonotic, companion animal, livestock, and wildlife tick-borne pathogens. We begin by illustrating how wildlife contribute directly and indirectly to the increase and geographic expansion of ticks and their associated pathogens. Wildlife provide blood meals for tick growth and reproduction; serve as pathogen reservoirs; and can disperse ticks and pathogens-either through natural movement (e.g., avian migration) or through human-facilitated movement (e.g., wildlife translocations and trade). We then discuss opportunities to manage tick-borne disease through actions directed at wildlife hosts. To conclude, we highlight key gaps in our understanding of the ecology of tick-host interactions, emphasizing that wildlife host communities are themselves a very dynamic component of tick-pathogen-host systems and therefore complicate management of tick-borne diseases, and should be taken into account when considering host-targeted approaches. Effective management of wildlife to reduce tick-borne disease risk further requires consideration of the 'human dimensions' of wildlife management. This includes understanding the public's diverse views and values about wildlife and wildlife impacts-including the perceived role of wildlife in fostering tick-borne diseases. Public health agencies should capitalize on the expertise of wildlife agencies when developing strategies to reduce tick-borne disease risks.

Parasite prevalence, infection intensity and richness in an endangered population, the Atlantic-Gaspésie caribou

The Atlantic-Gaspésie caribou (Rangifer tarandus caribou) population is a small isolated relict herd considered endangered according to the Canadian Species at Risk Act (SARA). This population has low recruitment and survival rates but the potential role of parasites on individual fitness is unknown. In this context, we explored the parasite status of this population with the aim of 1) assessing the occurrence and intensity of parasite infections and the spatial, temporal and individual variations, 2) quantifying parasite richness and investigating factors such as sex and host body condition that may be associated with this variable and 3) evaluating the effects of parasite infections on survival in the Atlantic-Gaspésie caribou population. We examined fecal samples from 32 animals captured in 2013–2014 for eggs, oocysts and larvae of parasites and detected 7 parasite species: dorsal-spined larvae protostrongylids, presumably Parelaphostrongylus andersoni based on PCR identification of a subset, Nematodirus odocoilei and other unidentified Strongyles, Trichuris sp., Capillaria sp., Moniezia sp. and Eimeria sp. For each caribou, mean parasite species richness was 1.8 ± 1.1 (SD). Sex, body condition, year and capture location did not explain parasite prevalence, intensity of infection or richness except for intensity of infection of Capillaria sp. that was positively influenced by body condition. Parasites did not influence survival although mortality was higher for males than for females. We suggest that the relatively low and common gastrointestinal and protostrongylid parasite infections will not be a short-term threat leading to extinction.

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Fecal pellets from Gaspésie-Atlantic caribou population were examined for parasites.

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We identified 7 parasite species and mean species richness reached 1.8/caribou.

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Parelaphostrongylus andersoni was identified using PCR identification.

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Capillaria sp. were found yet are rare in other wild caribou in Canada.

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Despite a male-biased mortality, parasite infection did not affect caribou survival.

Guidelines for the Detection of Babesia and Theileria Parasites

The genera Babesia and Theileria (phylum Apicomplexa, order Piroplasmida) are mainly transmitted by Ixodid ticks in which the sexual part of their life cycle followed by sporogony takes place. They include protozoan parasites that infect erythrocytes of a variety of vertebrate hosts, including domestic and wild animals, with some Babesia spp. also infecting humans. Babesia sporozoites transmitted in the tick's saliva during the bloodmeal directly infect erythrocytes, where they asexually multiply to produce pear-shaped merozoites in the process of merogony; whereas a pre-erythrocytic schizogonic life stage in leukocytes is found in Theileria and precedes merogony in the erythrocytes. The wide spectrum of Babesia and Theileria species and their dissimilar characteristics with relation to disease severity, transmission, epidemiology, and drug susceptibility stress the importance of accurate detection of babesiosis and theileriosis and their causative agents. These guidelines review the main methods currently used for the detection of Babesia and Theileria spp. for diagnostic purposes as well as epidemiological studies involving their vertebrate hosts and arthropod vectors. Serological methods were not included once they did not indicate current infection but rather exposure.

Parasites in ungulates of Arctic North America and Greenland: a view of contemporary diversity, ecology, and impact in a world under change

Parasites play an important role in the structure and function of arctic ecosystems, systems that are currently experiencing an unprecedented rate of change due to various anthropogenic perturbations, including climate change. Ungulates such as muskoxen, caribou, moose and Dall's sheep are also important components of northern ecosystems and are a source of food and income, as well as a focus for maintenance of cultural traditions, for northerners. Parasites of ungulates can influence host health, population dynamics and the quality, quantity and safety of meat and other products of animal origin consumed by people. In this article, we provide a contemporary view of the diversity of nematode, cestode, trematode, protozoan and arthropod parasites of ungulates in arctic and subarctic North America and Greenland. We explore the intricate associations among host and parasite assemblages and identify key issues and gaps in knowledge that emerge in a regime of accelerating environmental transition.

Detection of Anaplasma phagocytophilum and Babesia odocoilei DNA in Ixodes scapularis (Acari: Ixodidae) collected in Indiana

The blacklegged tick, Ixodes scapularis Say, first reported in Indiana in 1987, has now been detected in more than half of Indiana's counties. The first case of human granulocytic ehrlichiosis (human anaplasmosis) in Indiana was reported in 2002. We now report the detection of Anaplasma phagocytophilum and Babesia odocoilei (Emerson and Wright 1968) in I. scapularis ticks collected in northern Indiana. Using polymerase chain reaction analysis, 41 of 193 adult ticks (21.2%) collected from deer were positive for A. phagocytophylum, and 22 (11.4%) were positive for Babesia sp. Restriction fragment analysis of 12, and sequencing of another five of the amplified products identified these parasites as B. odocoilei. Five ticks (2.6%) were coinfected. Eight of 68 questing adult ticks (11.8%) were positive for A. phagocytophilum; seven (10.3%) were positive for Babesia sp. Six of the latter seven positive samples were determined to be B. odocoilei by restriction fragment analysis and sequencing of two samples. None of 39 pools of nymphs was positive for Babesia sp. Three of 15 ticks (20%) collected from a dog were positive for A. phagocytophilum and three ticks (20%) were positive for Babesia sp. One was confirmed as B. odocoilei. One tick was coinfected. This is the first report of the presence of these two agents in ticks in Indiana.

Seroprevalence of Babesia ovis in Spanish ibex (Capra pyrenaica) in Catalonia, northeastern Spain

A serologic survey was carried out in order to detect antibodies against Babesia ovis in a large population of Spanish ibex (Capra pyrenaica) from a hunting reserve in Catalonia, northeastern Spain. For this purpose, an indirect fluorescent antibody test (IFAT) was developed using a B. ovis isolate of ovine origin as antigen. Of the total 475 sera tested, 155 (32.6%) showed titres between 1:160 and 1:1280 and were considered positive. These results reveal that exposure of Spanish ibex to B. ovis is common in the studied area. No significant differences could be detected when comparing season or year of capture and age or sex of the animals in positive and negative samples. A high proportion of low titres was found in comparison to those reported by other researchers in sheep in Spain; this could be a consequence of the existence of some minor antigenic differences between B. ovis of domestic sheep and that found in Spanish ibex.