Project description:Babesia venatorum is an increasingly prominent zoonotic parasite that predominantly infects wild deer. Our molecular examination of Babesia infecting mammals in the United Kingdom identified 18S sequences in domestic sheep isolates identical to zoonotic B. venatorum. Identification of this parasite in livestock raises concerns for public health and farming policy in Europe.
Project description:BackgroundThe epidemiology of the zoonotic tick-transmitted parasite Babesia spp. and its occurrence in wild reservoir hosts in Sweden is unclear. In European deer, several parasite species, including Babesia capreoli and the zoonotic B. venatorum and B. divergens has been reported previously. The European roe deer, Capreolus capreolus, is an important and common part of the indigenous fauna in Europe, as well as an important host for Ixodes ricinus ticks, the vector of several Babesia spp. in Europe. Here, we aimed to investigate the occurrence of Babesia spp. in roe deer in Sweden.FindingsRoe deer (n = 77) were caught and sampled for blood. Babesia spp. was detected with a PCR assay targeting the 18S rRNA gene. The prevalence of Babesia spp. was 52%, and two species were detected; B. capreoli and B. venatorum in 44 and 7.8% of the individuals, respectively. Infection occurred both in summer and winter.ConclusionsWe showed that roe deer in Sweden, close to the edge of their northern inland distributional range, are infected with Babesia spp. The occurrence of B. venatorum in roe deer imply that it is established in Sweden and the zoonotic implication of this finding should be regarded to a greater extent in future.
Project description:Bovine babesiosis is a tick-transmitted disease caused by different species of Babesia. The white yak is a unique yak breed that lives only in Tianzhu in the Tibetan Autonomous County, Gansu Province, in northwestern China. Previous research using the ELISA method has confirmed that the white yak could become infected with B. bigemina. The objective of this study was the molecular detection and identification of Babesia species in white yaks. A total of 409 white yak blood samples were collected from 11 areas of the Tianzhu Tibetan Autonomous County in Northwest China from April to August, 2015. The V4 hypervariable region of Babesia 18S rRNA was amplified from extracted genomic DNA using nested PCR and sequenced. The nearly full-length sequence of 18S rRNA including the V4 region from the newly discovered Babesia was amplified and sequenced with Sanger method. PCR detection and sequencing indicated that 4/409 samples were positive for B. bigemina, 3/409 samples were positive for B. bovis, and 5/409 samples were positive for B. ovata. Additionally, a new Babesia species was found in 4/409 white yaks. A unique sequence of 1,627 bp was obtained from two of the four samples. The sequence was similar to Babesia species Akita (98.5%) found in Ixodes ovatus and B. venatorum (98%) and shared a 98% identity with B. divergens and a 98.1% identity with B. odocoilei. This study provides new data about Babesia infections in white yaks in northwestern China, and a new Babesia species similar to B. venatorum was identified in white yaks for the first time.
Project description:BACKGROUND: Bovine babesiosis is regarded as a limited health problem for Norwegian cows, and the incidence has decreased markedly since the 1930s. Rare cases of babesiosis in splenectomised humans from infection with Babesia divergens and B.venatorum have been described. The objective of this study was to determine whether birds can introduce Babesia-infected ticks. There are between 30 and 85 million passerine birds that migrate to Norway every spring. METHODS: Passerine birds were examined for ticks at four bird observatories along the southern Norwegian coast during the spring migrations of 2003, 2004 and 2005. The presence of Babesia was detected in the nymphs of Ixodes ricinus by real-time PCR. Positive samples were confirmed using PCR, cloning and phylogenetic analyses. RESULTS: Of 512 ticks examined, real-time PCR revealed five to be positive (1.0%). Of these, four generated products that indicated the presence of Babesia spp.; each of these were confirmed to be from Babesia venatorum (EU1). Two of the four B. venatorum-positive ticks were caught from birds having an eastern migratory route (P< 0.001). CONCLUSIONS: Birds transport millions of ticks across the North Sea, the Skagerrak and the Kattegat every year. Thus, even with the low prevalence of Babesia-infected ticks, a substantial number of infected ticks will be transported into Norway each year. Therefore, there is a continuous risk for introduction of new Babesia spp. into areas where I. ricinus can survive.
Project description:BackgroundHuman babesiosis is a common zoonosis caused by Babesia and is attracting an increasing concern worldwide. The natural course of babesiosis infection and how the human immune system changes during the course of babesiosis infection are not clear.MethodsWe followed up 1 case infected with Babesia venatorum for 5 years. The patient was immune-intact and received no standard treatment. Clinical data were obtained from medical records. Microbiological tests, ribonucleic acid (RNA) sequence, and serum cytokines and chemokines were detected at different time points.ResultsThe patient was confirmed as B venatorum infection based on his tick-bite history, clinical manifestations, and positive results of microbiological tests. The parasitemia of the patient persisted for approximately 2 months. With flu-like symptoms aggravating, most cytokines and chemokines in RNA and protein levels increased progressively and reached the peak when fever occurred; and their concentrations decreased to baseline during the same time as clearance of babesia parasites.ConclusionsBabesia venatorum infection could take a mild self-limited course in immune-intact individuals. The natural changes of most cytokines and chemokines demonstrated very similar trends, which correlated with blood parasitemia and clinical manifestations. Cytokine profiles involving multiple inflammatory cytokines might be a good indicator of babesia infection.
Project description:BackgroundBabesiosis is an uncommon but emerging tick-borne disease caused by the genus Babesia. In this case study, we report a case of human infection with a novel Babesia sp. in China.FindingsThe patient in question had been suffering from repetitive occurrences of mild fever of unknown origin and fatigue for 10 years. Ring forms, tetrads, and one or two dots of chromatin or trophozoite-like organisms were observed in the patient's thin blood smears and bone marrow smears. Using a confocal laser-scanning microscope, it was observed that the patient's serum had reactivity with the surface proteins of the B. microti strain. Electron microscopy revealed oval red blood cells with 1 ~ 2 μm of knob protrusions in the cellular membrane. The results of the Babesia-specific nested PCR assay for 18S rRNA confirmed the presence of Babesia infection. The construction of a phylogenetic relationship showed clustering with B. microti and B. duncani, which was identified as a novel Babesia species and named as Babesia sp. XXB/HangZhou. Azithromycin, doxycycline, and moxifloxacin hydrochloride were shown to relieve symptoms but were not as effective after continuous usage. After atovaquone (Mepron®) administration, the patient recovered from fever and tested negative for detection of Babesia-specific genes.ConclusionBabesia sp. XXB/HangZhou is a novel Babesia species, which causes mild babesiosis in an immunocompetent patient.
Project description:BackgroundTo increase understanding of human bacterial and parasitic pathogens in bats, we investigated the prevalence of Babesia spp., Rickettsia spp., Anaplasma spp. and Coxiella burnetii in bats from China.MethodsBats were captured from Mengyin County, Shandong Province of China using nets. DNA was extracted from the blood and spleen of bats for molecular detection of Babesia spp., Rickettsia spp., Anaplasma spp. and Coxiella burnetii with specific primers for each species.ResultsA total of 146 spleen samples and 107 blood samples of insectivorous bats, which belonged to 6 species within two families, were collected from Mengyin County, Shandong Province of China. We found that two Eptesicus serotinus (2/15, 13.3%) were positive for Babesia vesperuginis. We were unable to detect genomic sequences for Rickettsia spp., Anaplasma spp. and Coxiella burnetii.ConclusionsTo our knowledge, our study showed for the first time the presence of Babesia vesperuginis in Eptesicus serotinus collected from China, suggesting that Babesia vesperuginis has a broad host species and geographical distribution.
Project description:Most reported U.S. zoonotic cases of babesiosis have occurred in the Northeast and been caused by Babesia microti. In Washington State, three cases of babesiosis have been reported previously, which were caused by WA1 (for "Washington 1")-type parasites. We investigated a case of babesiosis in Washington in an 82-year-old man whose spleen had been removed and whose parasitemia level was 41.4%. The complete 18S ribosomal RNA gene of the parasite was amplified from specimens of his whole blood by polymerase chain reaction. Phylogenetic analysis showed the parasite is most closely related, but not identical, to B. divergens (similarity score, 99.5%), a bovine parasite in Europe. By indirect fluorescent-antibody testing, his serum reacted to B. divergens but not to B. microti or WA1 antigens. This case demonstrates that babesiosis can be caused by novel parasites detectable by manual examination of blood smears but not by serologic or molecular testing for B. microti or WA1-type parasites.
Project description:BackgroundBabesiosis is an important haemoparasitic disease, caused by the infection and subsequent intra-erythrocytic multiplication of protozoa of the genus Babesia that impacts the livestock industry and animal health. The distribution, epidemiology and genetic characterization of B. bigemina, B. bovis, and B. ovata in cattle in China as well as the prevalence of these protozoan agents were assessed.MethodsA total of 646 blood specimens from cattle, dairy cattle and yaks from 14 provinces were collected and tested for the presence of the three Babesia species via a specific nested PCR assay based on the rap-1 and ama-1 genes. The PCR results were confirmed by DNA sequencing. Gene sequences and the genetic characterization were determined for selected positive samples from each sampling area.ResultsOf a total of 646 samples, 134 (20.7 %), 60 (9.3 %) and 10 (1.5 %) were positive for B. bovis, B. bigemina and B. ovata infections, respectively. Mixed infections were found in 7 of 14 provinces; 43 (6.7 %) samples were infected with B. bovis and B. bigemina. Three samples (0.5 %) exhibited a co-infection with B. bovis and B. ovata, and 6 (0.9 %) were infected with all three parasites. The rap-1a gene of B. bovis indicated a high degree of sequence heterogeneity compared with other published rap-1a sequences worldwide and was 85-100 % identical to B. bovis rap-1a sequences in Chinese isolates. B. bigemina rap-1c and B. ovata ama-1 genes were nearly identical, with 97.8-99.3 % and 97.8-99.6 % sequence identity, respectively, in GenBank.ConclusionsPositive rates of B. bovis and B. bigemina infection are somewhat high in China. The B. bovis infection in yaks was first reported. The significant sequence heterogeneity in different variants of the rap-1a gene from Chinese B. bovis isolates might be a great threat to the cattle industry if RAP-1a protein is used as immunological antigen against Babesia infections in China. The data obtained in this study can be used to plan effective control strategies against babesiosis in China.
Project description:BackgroundThe protozoan parasite Babesia microti that causes the zoonotic disease babesiosis resides in the erythrocytes of its mammalian host during its life-cycle. No effective vaccines are currently available to prevent Babesia microti infections.MethodsWe previously identified a highly seroactive antigen, named Bm8, as a B. microti conserved erythrocyte membrane-associated antigen, by high-throughput protein chip screening. Bioinformatic and phylogenetic analysis showed that this membrane-associated protein is conserved among apicomplexan hemoprotozoa, such as members of genera Babesia, Plasmodium and Theileria. We obtained the recombinant protein Bm8 (rBm8) by prokaryotic expression and purification.ResultsImmunofluorescence assays confirmed that Bm8 and its Plasmodium homolog were principally localized in the cytoplasm of the parasite. rBm8 protein was specifically recognized by the sera of mice infected with B. microti or P. berghei. Also, mice immunized with Bm8 polypeptide had a decreased parasite burden after B. microti or P. berghei infection.ConclusionsPassive immunization with Bm8 antisera could protect mice against B. microti or P. berghei infection to a certain extent. These results lead us to hypothesize that the B. microti conserved erythrocyte membrane-associated protein Bm8 could serve as a novel broad-spectrum parasite vaccine candidate since it elicits a protective immune response against Babesiosis and Plasmodium infection.