Molecular detection of Babesia vesperuginis in bats from Lithuania

Babesia vesperuginis is an intraerythrocytic protozoan parasite that circulates among bats and ticks in many countries worldwide. However, the distribution of B. vesperuginis in the Baltic region has not been studied. A total of 86 dead bats from eight different species were collected and screened for Babesia spp. using real-time PCR. Overall, 52.3% (45/86) of the bats were found positive for Babesia spp. The prevalence of Babesia spp. in different organs varied, with the highest prevalence observed in heart tissues (37.0%) and the lowest in liver tissues (22.2%). However, the observed differences in prevalence among organs were not statistically significant. Blood samples from 125 bats of nine different species were also analyzed for Babesia spp. prevalence using real-time PCR and nested PCR. The results showed a prevalence of 35.2% and 22.4%, respectively. Moreover, 28.3% (17/60) of the examined blood samples were confirmed positive for Babesia spp. through blood smear analysis. The total of 32 partial sequences of the 18S rRNA gene derived in this study were 100% identical to B. vesperuginis sequences from GenBank. In eight species of bats, Pipistrellus nathusii, Pipistrellus pipistrellus, Pipistrellus pygmaeus, Vespertilio murinus, Eptesicus nilssonii, Eptesicus serotinus, Myotis daubentonii and Nyctalus noctula, Babesia parasites were identified. In E. nilssonii, Babesia spp. was identified for the first time.

Molecular detection of Babesia spp. in European bison (Bison bonasus) and their ticks

Babesia spp. are tick-borne haemoparasites that infect a wide range of domestic and wild mammals. Free-ranging ungulates are considered to be important reservoir hosts of Babesia parasites. The European bison (Bison bonasus) is a large and rare ungulate species, reintroduced into the forests of Central Europe after an absence of several decades. Owing to their protected status, studies of tick-borne pathogens in European bison have so far been rare and fragmented. The aim of this study was to investigate the presence of Babesia infection in free-ranging and captive herds of European bison and their ticks. Tissue samples obtained from 37 European bison individuals and 242 ticks belonging to two species, Ixodes ricinus and Dermacentor reticulatus, collected from bison were subjected to PCR analysis of the 18S rRNA gene followed by sequencing. Babesia spp. were detected in 8% of the samples from European bison and in 11% of the ticks. Sequence analysis of partial 18S rRNA gene indicated the presence of B. divergens and B. capreoli in European bison, while B. divergens, B. microti and B. venatorum were detected in ixodid ticks. To the best of authors' knowledge, this is the first molecular detection and characterization of Babesia spp. in European bison and their ticks.

Surveillance for Babesia odocoilei in Hunter-Harvested Wild-Elk (Cervus elaphus canadensis) from Pennsylvania, USA (2016-2017)

Babesia odocoilei is a tick-borne protozoal parasite which infects the erythrocytes of members of the families Cervidae and Bovidae. Infection can result in hemolytic anemia, lethargy, anorexia, and death. The reservoir host of B. odocoilei is the white-tailed deer (Odocoileus virginianus); however, infections with overt disease have only been documented in reindeer (Rangider tarandu tarandus), caribou (Rangider tarandu caribou) and captive elk (Cervus elaphus canadensis). Infected elk may remain asymptomatic, creating the risk for dissemination of the pathogen when elk are relocated. Additionally, infected asymptomatic elk may contribute to the spread of B. odocoilei in the local wildlife/captive population via feeding ticks. Information regarding endemic regions of B. odocoilei infection is limited due to frequent asymptomatic infections and a lack of targeted surveillance of B. odocoilei in wildlife. To obtain data on B. odocoilei infection in wild elk in Pennsylvania, we tested blood samples collected from 190 hunter-harvested wild elk between 2016 and 2017. Of the 190 blood samples tested, 18.4% (35/190) tested positive for Babesia spp. Genetic sequencing of the positive samples showed a 98.0–100.0% match for B. odocoilei. No other Babesia species were identified. Results of this study documents B. odocoilei infection within hunter-harvested wild elk from Pennsylvania.

Three cases of canine babesiosis caused by Babesia odocoilei-like parasites in Japan

Babesia odocoilei-like parasites were first reported in 2003, and their virulence and hosts remain unknown. We report three cases of dogs with canine babesiosis in Iwate Prefecture. Since Iwate Prefecture area is an area of Japan where canine babesiosis is not endemic, we suspected that these cases of canine babesiosis were caused by B. odocoilei-like parasites. In the present study, we tried to identify the Babesia species that caused these cases of canine babesiosis. To classify Babesia parasites, the heat shock protein 70 (HSP70) gene was examined. Accordingly, we cloned and analyzed the HSP70 gene sequences of B. odocoilei-like parasites from three Ixodes ovatus ticks. It was determined that the nucleotide sequence of the HSP70 gene of the B. odocoilei-like parasites was not consistent with that of B. odocoilei, which suggests that these parasites were from a different species than B. odocoilei. Second, we identified the Babesia species that infected the three dogs by using the HSP70 gene and 18S rRNA. A partial HSP70 gene of B. odocoilei-like parasites was detected in the three dogs, but that of B. gibsoni was not detected. Additionally, a partial sequence of 18S rRNA of B. odocoilei-like parasites was detected in two dogs. These results demonstrated that two dogs were certainly infected with B. odocoilei-like parasites and that one dog was probably infected with B. odocoilei-like parasites. Therefore, these dogs were diagnosed with canine babesiosis due to the presence of B. odocoilei-like parasites. As there were only three cases, additional cases are needed to confirm our findings.

A historical review of Babesia spp. associated with deer in Europe: Babesia divergens/Babesia divergens-like, Babesia capreoli, Babesia venatorum, Babesia cf. odocoilei

This review is intended to provide an overview of the occurrence and diversity of Babesia spp. in European deer. Babesiosis is an emerging vector-borne disease with negative implications on animal and public health. Cervidae are important hosts for Ixodidae ticks, playing a critical role in the epidemiology of the parasite. Deer are susceptible to different Babesia spp., some of them with zoonotic potential. The infection is usually asymptomatic with high prevalence rates, although some fatal cases due to B. capreoli and B. venatorum have been reported. In Europe, 3 main Babesia spp. have been described in deer: Babesia divergens/B. divergens-like, B. capreoli and B. venatorum. Additionally, close relatives of B. odocoilei, the Babesia species of the American white-tailed deer (Odocoileus virginianus), have been isolated in several European countries. The occurrence of B. divergens/B. divergens-like generated concerns about the role of cervidae in the life cycle of the parasite, and the potential threat for public health. Few human cases have been attributed to B. venatorum so far, including hunters. Although this species is strictly related to the presence of roe deer (Capreolus capreolus), it has been occasionally reported in moose (Alces alces) and captive reindeer (Rangifer tarandus). Over recent years, vector-borne diseases received increased attention from International Organizations. However, technical difficulties persist, affecting surveillance efficiency. Given the veterinary and zoonotic importance of babesiosis, the author advocates the need for an effective monitoring at wildlife-domestic animals-humans interface and the implementation of management plans to reduce the risk of Babesia spp. infection for both humans and domestic animals.

Anaplasma phagocytophilum and Babesia Species of Sympatric Roe Deer (Capreolus capreolus), Fallow Deer (Dama dama), Sika Deer (Cervus nippon) and Red Deer (Cervus elaphus) in Germany

(1) Background: Wild cervids play an important role in transmission cycles of tick-borne pathogens; however, investigations of tick-borne pathogens in sika deer in Germany are lacking. (2) Methods: Spleen tissue of 74 sympatric wild cervids (30 roe deer, 7 fallow deer, 22 sika deer, 15 red deer) and of 27 red deer from a farm from southeastern Germany were analyzed by molecular methods for the presence of Anaplasma phagocytophilum and Babesia species. (3) Results: Anaplasma phagocytophilum and Babesia DNA was demonstrated in 90.5% and 47.3% of the 74 combined wild cervids and 14.8% and 18.5% of the farmed deer, respectively. Twelve 16S rRNA variants of A. phagocytophilum were delineated. While the infection rate for A. phagocytophilum among the four cervid species was similar (71.4% to 100%), it varied significantly for Babesia between roe deer (73.3%), fallow deer (14.3%), sika deer (27.3%) and red deer (40.0%). Deer ≤2 years of age tested significantly more often positive than the older deer for both A. phagocytophilum and Babesia species. (4) Conclusions: This study confirms the widespread occurrence of A. phagocytophilum and Babesia species in wild cervids and farmed red deer in Germany and documents the co-occurrence of the two tick-borne pathogens in free-ranging sika deer.

Diversity of Babesia spp. in cervid ungulates based on the 18S rDNA and cytochrome c oxidase subunit I phylogenies

Free ranging ungulates, represented in Europe mostly by several deer species, are important hosts for ticks and reservoirs of tick-borne infections. A number of studies have focused on the prevalence of tick borne pathogens in deer chiefly with the aim to determine their potential role as reservoir hosts for important human and livestock pathogens. However, genetic similarity of Babesia spp. forming a group commonly termed as a clade VI that accommodates the deer piroplasms, complicates this task and has led to the description of a bewildering array of poorly characterised strains. This study aims to resolve this issue by using two independent genetic loci, nuclear 18S rRNA and mitochondrial cytochrome c oxidase subunit I genes, used in parallel to identify Babesia isolates in free-ranging red, sika, and roe deer in two areas of their co-occurrence in the Czech Republic. The COX1 loci, in contrast to 18S rRNA gene, shows a clear difference between interspecific and intraspecific variation at the nucleotide level. The findings confirm B. divergens, Babesia sp. EU1 and B. capreoli in studied deer species as well as common presence of another unnamed species that matches a taxon previously referred to as Babesia sp. or Babesia cf. odocoilei or Babesia CH1 group in several other sites throughout Europe. The invasive sika deers enter the life cycle of at least three piroplasmid species detected in native deer fauna. The presence of B. divergens in both sika and red deer in an area where bovine babesiosis is apparently absent raises important questions regarding the epidemiology, host specificity and taxonomic status of the parasite.

Prevalence and co-infection with tick-borne Anaplasma phagocytophilum and Babesia spp. in red deer (Cervus elaphus) and roe deer (Capreolus capreolus) in Southern Norway

Anaplasma phagocytophilum and Babesia spp. are causative agents of tick-borne infections that are increasingly considered as a threat to animal and public health. To assess the role of cervids in the maintenance of zoonotic pathogens in Norway, we investigated the prevalence of A. phagocytophilum and Babesia spp. in free-ranging roe deer and red deer. Initial screening of spleen samples of 104 animals by multiplex real-time PCR targeting the major surface protein (msp2) gene and 18S rRNA revealed the presence of A. phagocytophilum infection in 81.1% red deer (Cervus elaphus) and 88.1% roe deer (Capreolus capreolus), and Babesia spp. parasites in 64.9% red deer and 83.6% roe deer, respectively. Co-infections were found in 62.2% red deer and 79.9% roe deer. Nested PCR and sequence analysis of partial msp4 and 18S rRNA genes were performed for molecular characterization of A. phagocytophilum strains and Babesia species. A total of eleven A. phagocytophilum msp4 gene sequence variants were identified: five different variants were 100% identical to corresponding A. phagocytophilum sequences deposited in the GenBank database, while other six sequence variants had unique nucleotide polymorphisms. Sequence analysis of the 18S rRNA gene demonstrated the presence of multiple Babesia species, including Babesia capreoli, Babesia divergens, Babesia venatorum and Babesia odocoilei/Babesia cf. odocoilei. This study is the first report demonstrating the prevalence and molecular characterization of A. phagocytophilum strains and Babesia species in roe deer and red deer in Norway. The high infection and co-infection rates with A. phagocytophilum and Babesia spp. in red deer and roe deer suggest that these cervids may play an important role in the transmission of single and multiple pathogens.