ABSTRACT
Babesia ovis, transmitted by Rhipicephalus bursa ticks, is the causative agent of ovine babesiosis, a disease characterized by fever, anemia, hemoglobinuria, and high mortality in sheep. This study investigates whether sheep that survived babesiosis without treatment can serve as a source of infection for B. ovis-free host-seeking R. bursa larvae in a later season. Three donor sheep were experimentally infected with B. ovis, and after six months, persistence of B. ovis was assessed through blood and tick transmission experiments. Blood from donor sheep was intravenously injected into three recipient sheep, while donor sheep were also infested with B. ovis-free R. bursa larvae. Engorged nymphs molted to adults, and new recipient sheep were infested with these ticks. All recipient sheep were monitored for B. ovis for 100 days using microscopic, serological, and molecular approaches. The presence of B. ovis was confirmed in the recipient sheep that received blood, leading to clinical infection in two. However, no B. ovis was detected in recipient sheep infested with ticks. These results suggest that sheep recovering from B. ovis infection do not serve as a source of infection for R. bursa larvae in subsequent seasons.
Subject(s)
Babesia , Babesiosis , Larva , Rhipicephalus , Sheep Diseases , Animals , Sheep , Babesiosis/transmission , Babesiosis/parasitology , Rhipicephalus/parasitology , Sheep Diseases/parasitology , Sheep Diseases/transmission , Babesia/isolation & purification , Babesia/pathogenicity , Female , Chronic DiseaseABSTRACT
BACKGROUND: Babesia spp. are protozoan parasites that infect the red blood cells of domesticated animals, wildlife and humans. A few cases of giant pandas (a flagship species in terms of wildlife conservation) infected with a putative novel Babesia sp. have been reported. However, comprehensive research on the morphological and molecular taxonomic classification of this novel Babesia sp. is still lacking. This study was designed to close this gap and formally describe this new Babesia sp. infecting giant pandas. METHODS: Detailed morphological, molecular and phylogenetic analyses were conducted to characterise this Babesia sp. and to assess its systematic relationships with other Babesia spp. Blood samples from giant pandas infected with Babesia were subjected to microscopic examination. The 18S ribosomal RNA (18S rRNA), cytochrome b (cytb) and mitochondrial genome (mitogenome) of the new Babesia sp. were amplified, sequenced and assembled using DNA purified from blood samples taken from infected giant pandas. Based on the newly generated 18S rRNA, cytb and mitogenome sequences, phylogenetic trees were constructed. RESULTS: Morphologically, the Babesia sp. from giant pandas exhibited various forms, including round to oval ring-shaped morphologies, resembling those found in other small canine Babesia spp. and displaying typical tetrads. Phylogenetic analyses with the 18S rRNA, cytb and mitogenome sequences revealed that the new Babesia sp. forms a monophyletic group, with a close phylogenetic relationship with the Babesia spp. that infect bears (Ursidae), raccoons (Procyonidae) and canids (Canidae). Notably, the mitogenome structure consisted of six ribosomal large subunit-coding genes (LSU1-6) and three protein-coding genes (cytb, cox3 and cox1) arranged linearly. CONCLUSIONS: Based on coupled morphological and genetic analyses, we describe a novel species of the genus Babesia, namely, Babesia ailuropodae n. sp., which infects giant pandas.
Subject(s)
Babesia , Babesiosis , Cytochromes b , Phylogeny , RNA, Ribosomal, 18S , Ursidae , Animals , Babesia/genetics , Babesia/classification , Babesia/isolation & purification , Ursidae/parasitology , RNA, Ribosomal, 18S/genetics , Babesiosis/parasitology , Cytochromes b/genetics , Genome, Mitochondrial , DNA, Protozoan/geneticsABSTRACT
Babesia is a tick-transmitted parasite that infects wild and domestic animals, causes babesiosis in humans, and is an increasing public health concern. Here, we investigated the prevalence and molecular characteristics of Babesia infections in the rodents in Southeastern Shanxi, China. Small rodents were captured, and the liver and spleen tissues were used for Babesia detection using traditional PCR and sequencing of the partial 18S rRNA gene. The analysis revealed that 27 of 252 small rodents were positive for Babesia, with an infection rate of 10.71%. The infection rates in different sexes and rodent tissues were not statistically different, but those in different rodent species, habitats, and sampling sites were statistically different. The highest risk of Babesia infection was observed in Niviventer confucianus captured from the forests in Huguan County. Forty-three sequences from 27 small rodents positive for Babesia infection were identified as Babesia microti, including 42 sequences from 26 N. confucianus, and one sequence from Apodemus agrarius. Phylogenetic analysis showed that all sequences were clustered together and had the closest genetic relationship with Babesia microti strains isolated from Rattus losea and N. confucianus in China, and belonged to the Kobe-type, which is pathogenic to humans. Compared to other Kobe-type strains based on the nearly complete 18S rRNA gene, the sequences obtained in this study showed the difference by 1-3 bp. Overall, a high prevalence of Babesia microti infection was observed in small rodents in Southeastern Shanxi, China, which could benefit us to take the implementation of relevant prevention and control measures in this area.
Subject(s)
Babesia microti , Babesiosis , Phylogeny , RNA, Ribosomal, 18S , Rodentia , Animals , Babesia microti/genetics , Babesia microti/isolation & purification , China/epidemiology , Babesiosis/epidemiology , Babesiosis/parasitology , Prevalence , Rodentia/parasitology , RNA, Ribosomal, 18S/genetics , Female , Male , Rodent Diseases/epidemiology , Rodent Diseases/parasitologyABSTRACT
BACKGROUND: In recent years, Babesia and Bartonella species co-infections in patients with chronic, nonspecific illnesses have continued to challenge and change the collective medical understanding of "individual pathogen" vector-borne infectious disease dynamics, pathogenesis and epidemiology. The objective of this case series is to provide additional molecular documentation of Babesia odocoilei infection in humans in the Americas and to emphasize the potential for co-infection with a Bartonella species. METHODS: The development of improved and more sensitive molecular diagnostic techniques, as confirmatory methods to assess active infection, has provided increasing clarity to the healthcare community. RESULTS: Using a combination of different molecular diagnostic approaches, infection with Babesia odocoilei was confirmed in seven people suffering chronic non-specific symptoms, of whom six were co-infected with one or more Bartonella species. CONCLUSIONS: We conclude that infection with Babesia odocoilei is more frequent than previously documented and can occur in association with co-infection with Bartonella spp.
Subject(s)
Babesia , Babesiosis , Bartonella Infections , Bartonella , Coinfection , Humans , Babesiosis/epidemiology , Babesiosis/complications , Babesiosis/parasitology , Coinfection/epidemiology , Coinfection/microbiology , Coinfection/parasitology , Bartonella Infections/epidemiology , Bartonella Infections/microbiology , Bartonella Infections/complications , Babesia/isolation & purification , Babesia/genetics , Bartonella/isolation & purification , Bartonella/genetics , Male , Female , Middle Aged , Adult , Americas/epidemiology , Aged , Molecular Diagnostic TechniquesABSTRACT
Babesia species are intraerythrocytic protozoan parasites that infect a variety of hosts. The goal of this study was to evaluate the piroplasm species present in skunks in various states in the United States and determine whether there was any geographic variation. Spleen, whole blood, or blood on filter paper were received from Pennsylvania, Kentucky, North Carolina, South Carolina, Georgia, Missouri, Louisiana, Texas, Kansas, and California, and were tested for Babesia sp. We tested four species of skunks including striped skunk (Mephitis mephitis, n = 72), eastern spotted skunk (Spilogale putorius, n = 28), western spotted skunk (Spilogale gracilis, n = 15), and hog-nosed skunk (Conepatus leuconotus, n = 11). A PCR assay targeting the 18S rRNA region and cox1 region were used to determine if skunks were infected with piroplasms and for phylogenetic analyses. A total of 48.4% (61/126) of skunks tested positive for a Babesia species. Both the 18S and cox1 analysis supported a skunk-specific Babesia microti-like sp. of carnivores as well as a species in the B. microti complex that is phylogenetically unique from both B. microti of humans and the B. microti-like sp. of carnivores. In the 18S analysis, there was a third species of Babesia in hog-nosed skunks in the western piroplasm group. This study shows that at least three species of piroplasms occur in skunk species in the United States and further highlights the importance of phylogenetic analyses and the use of multiple gene targets when studying piroplasms.
Title: Diversité des Babesia spp. chez des mouffettes provenant d'États sélectionnés des États-Unis. Abstract: Les espèces de Babesia sont des protozoaires parasites intraérythrocytaires qui infectent divers hôtes. Le but de cette étude était d'évaluer les espèces de piroplasmes présentes chez les mouffettes dans divers états des États-Unis et de déterminer s'il existait une variation géographique. Des rates, du sang total ou du sang sur papier filtre ont été reçus de Pennsylvanie, du Kentucky, de Caroline du Nord, de Caroline du Sud, de Géorgie, du Missouri, de Louisiane, du Texas, du Kansas et de Californie, et ont été testés pour Babesia sp. Nous avons testé quatre espèces de mouffettes, dont la mouffette rayée (Mephitis mephitis, n = 72), la mouffette tachetée de l'Est (Spilogale putorius, n = 28), la mouffette tachetée de l'Ouest (Spilogale gracilis, n = 15) et la mouffette à nez plat (Conepatus leuconotus, n = 11). Un test PCR ciblant la région de l'ARNr 18S et la région cox1 a été utilisé pour déterminer si les mouffettes étaient infectées par des piroplasmes et pour des analyses phylogénétiques. Au total, 48,4 % (61/126) des mouffettes ont été testées positives pour une espèce de Babesia. Les analyses du 18S et du cox1 ont toutes deux confirmé une espèce de type Babesia microti de carnivores spécifique aux mouffettes ainsi qu'une espèce du complexe B. microti qui est phylogénétiquement unique à la fois par rapport à B. microti de l'homme et à l'espèce des carnivores. Dans l'analyse 18S, il y avait une troisième espèce de Babesia chez les mouffettes à nez plat du groupe des piroplasmes de l'ouest. Cette étude montre qu'au moins trois espèces de piroplasmes sont présentes chez les espèces de mouffettes aux États-Unis et souligne en outre l'importance des analyses phylogénétiques et de l'utilisation de plusieurs cibles génétiques lors de l'étude des piroplasmes.
Subject(s)
Babesia , Babesiosis , Mephitidae , Phylogeny , RNA, Ribosomal, 18S , Babesiosis/epidemiology , Babesiosis/parasitology , Babesia/classification , Babesia/isolation & purification , Babesia/genetics , Animals , United States/epidemiology , RNA, Ribosomal, 18S/genetics , Mephitidae/parasitology , DNA, Protozoan , Genetic Variation , Polymerase Chain ReactionABSTRACT
BACKGROUND: Babesiosis is a tick-borne infection caused by piroplasmid protozoa and associated with anemia and severe disease in humans, domestic animals and wildlife. Domestic cats are infected by at least six Babesia spp. that cause clinical disease. METHODS: Infection with a piroplasmid species was detected by microscopy of stained blood smears in three sick cats from Israel. Genetic characterization of the piroplasmid was performed by PCR amplification of the 18S rRNA, cytochorme B (CytB) and heat shock protein 70 (HSP70) genes and the internal transcribed spacer (ITS) locus, DNA sequencing and phylogenetic analysis. In addition, Haemaphysalis adleri ticks collected from two cats were analyzed by PCR for piroplasmids. RESULTS: The infected cats presented with anemia and thrombocytopenia (3/3), fever (2/3) and icterus (1/3). Comparison of gene and loci sequences found 99-100% identity between sequences amplified from different cats and ticks. Constructed phylogenetic trees and DNA sequence comparisons demonstrated a previously undescribed Babesia sp. belonging to the Babesia sensu stricto (clade X). The piroplasm forms detected included pear-shaped merozoite and round-to-oval trophozoite stages with average sizes larger than those of Babesia felis, B. leo and B. lengau and smaller than canine Babesia s.s. spp. Four of 11 H. adleri adult ticks analyzed from cat # 3 were PCR positive for Babesia sp. with a DNA sequence identical to that found in the cats. Of these, two ticks were PCR positive in their salivary glands, suggesting that the parasite reached these glands and could possibly be transmitted by H. adleri. CONCLUSIONS: This study describes genetic and morphological findings of a new Babesia sp. which we propose to name Babesia galileei sp. nov. after the Galilee region in northern Israel where two of the infected cats originated from. The salivary gland PCR suggests that this Babesia sp. may be transmitted by H. adleri. However, incriminating this tick sp. as the vector of B. galilee sp. nov. would require further studies.
Subject(s)
Babesia , Babesiosis , Cat Diseases , Phylogeny , Animals , Cats , Babesia/genetics , Babesia/isolation & purification , Babesia/classification , Babesiosis/parasitology , Babesiosis/epidemiology , Cat Diseases/parasitology , Israel/epidemiology , RNA, Ribosomal, 18S/genetics , Male , DNA, Protozoan/genetics , Female , Sequence Analysis, DNAABSTRACT
Babesia spp. and Theileria spp. are tick-borne protozoan parasites with veterinary importance. In China, epidemiological and genetic investigations on many Babesia and Theileria species were still absent in many areas and many tick species. From Aug 2021 to May 2023, 645 ticks were collected from the body surface of domestic animals (camels, goats, sheep, and cattle) using tweezers in seven counties in three provinces including Xinjiang (Qitai, Mulei, Hutubi, and Shihezi counties), Chongqing (Youyang and Yunyang counties), and Qinghai (Huangzhong county). Three tick species were morphologically and molecularly identified (334 Hyalomma asiaticum from Xinjiang, 245 Rhipicephalus microplus from Chongqing, and 66 Haemaphysalis qinghaiensis from Qinghai). A total of three Babesia species and two Theileria species were detected targeting the 18S gene. The COI and cytb sequences were also recovered from Babesia strains for further identification. In R. microplus from Chongqing, Babesia bigemina, the agent of bovine babesiosis, was detected. Notably, in H. asiaticum ticks from Xinjiang, a putative novel genotype of Babesia caballi was identified (0.90%, 3/334), whose COI and cytb genes have as low as 85.82% and 90.64-90.91% nucleotide identities to currently available sequences. It is noteworthy whether the sequence differences of its cytb contribute to the drug resistance of this variant due to the involvement of cytb in the drug resistance of Babesia. In addition, Theileria orientalis and Theileria annulata were detected in R. microplus from Chongqing (12.20%, 31/245) and H. asiaticum from Xinjiang (1.50%, 5/334), respectively. These results suggest that these protozoan parasites may be circulating in domestic animals in these areas. The pathogenicity of the novel genotype of B. caballi also warrants further investigation.
Subject(s)
Babesia , Genotype , Theileria , Animals , Babesia/genetics , Babesia/isolation & purification , Babesia/classification , Theileria/genetics , Theileria/isolation & purification , China/epidemiology , Cattle , Phylogeny , Ixodidae/parasitology , Sheep , Babesiosis/parasitology , Babesiosis/epidemiology , Theileriasis/epidemiology , Theileriasis/parasitology , GoatsABSTRACT
Equine piroplasmosis (EP) is a global worldwide infection, which can lead to the death of animals. Despite the causative agents of EP being well studied, there are no data on the distribution and genetic characteristics of EP agents in any region of Russia. In this study, blood samples from 750 horses from Novosibirsk province, Irkutsk province, and Altai region of Russian Siberia were examined for the presence of EP agents. Theileria equi and Babesia caballi were detected in all examined regions, with mean prevalence rates of 60.4% and 7.2%, respectively. The identified pathogens were genetically characterized by the 18S rRNA gene. The determined T. equi sequences were highly conserved and belonged to genotypes A and E, with genotype E being found in 88.6% of genotyped samples. In contrast to T. equi, B. caballi sequences were genetically diverse. Seven sequence variants of B. caballi were identified, and only two of them matched known sequences from the GenBank database. The determined B. caballi sequences belonged to four distinct branches within genotype A. Mixed infections with several variants of B. caballi or with T. equi and B. caballi were common. The conducted phylogenetic analysis based on all available B. caballi sequences of the 18S rRNA gene (> 900 bp) from GenBank and from this study first demonstrated the presence of five monophyletic clusters within genotype A and three clusters within genotype B. Thus, the genetic study of B. caballi from Siberia has significantly expanded the data on the genetic diversity of this pathogen.
Subject(s)
Babesia , Babesiosis , Genetic Variation , Genotype , Horse Diseases , Phylogeny , RNA, Ribosomal, 18S , Theileria , Theileriasis , Animals , Theileria/genetics , Theileria/classification , Theileria/isolation & purification , Babesia/genetics , Babesia/classification , Babesia/isolation & purification , Babesiosis/epidemiology , Babesiosis/parasitology , Horses/parasitology , Horse Diseases/parasitology , Horse Diseases/epidemiology , Theileriasis/epidemiology , Theileriasis/parasitology , RNA, Ribosomal, 18S/genetics , Prevalence , Russia/epidemiology , DNA, Protozoan/genetics , Siberia/epidemiology , Sequence Analysis, DNA , DNA, Ribosomal/genetics , DNA, Ribosomal/chemistryABSTRACT
Tick-borne diseases in animals are increasing rapidly worldwide, but there is insufficient information about tick-borne diseases infecting dogs in southern Egypt. Thus, in the current study, we detected the presence of Anaplasma marginale (A. marginale) and Babesia canis vogeli (B. canis vogeli) in the blood of dogs. The results revealed that 4/100 (4%) were positive, and a higher infection rate was found in males (75%), than females (25%). The phylogenetic analysis for the major surface protein 4 (msp4) gene in this study was compared with amplicons separate from other reported isolates with alignment by identity 100% with cattle and camels from Egypt, and the phylogenetic analysis for the B. canis vogeli small subunit ribosomal RNA (SSU rRNA) gene in this study identified identity by 99.89% with dogs from Egypt. This report is considered the first report in southern Egypt about A. marginale in dogs based on the sequence analysis of the msp4 gene, providing new data for the classification and identification of A. marginale in dogs compared to A. marginale isolated from other animals in southern Egypt.
Subject(s)
Anaplasma marginale , Anaplasmosis , Babesia , Babesiosis , Dog Diseases , Phylogeny , Animals , Dogs , Egypt/epidemiology , Babesia/genetics , Babesia/isolation & purification , Babesia/classification , Anaplasmosis/microbiology , Anaplasmosis/epidemiology , Anaplasmosis/diagnosis , Anaplasma marginale/genetics , Anaplasma marginale/isolation & purification , Dog Diseases/parasitology , Dog Diseases/microbiology , Dog Diseases/diagnosis , Babesiosis/parasitology , Babesiosis/epidemiology , Babesiosis/diagnosis , Female , MaleABSTRACT
Pathogens such as Plasmodium, Babesia, and Theileria invade and multiply within host red blood cells, leading to the pathological consequences of malaria, babesiosis, and theileriosis. Establishing continuous in vitro culture systems and suitable animal models is crucial for studying these pathogens. This review spotlights the Babesia duncani in culture-in mouse (ICIM) model as a promising resource for advancing research on the biology, pathogenicity, and virulence of intraerythrocytic parasites. The model offers practical benefits, encompassing well-defined culture conditions, ease of manipulation, and a well-annotated genome. Moreover, B. duncani serves as a surrogate system for drug discovery, facilitating the evaluation of new antiparasitic drugs in vitro and in animals, elucidating their modes of action, and uncovering potential resistance mechanisms. The B. duncani ICIM model thus emerges as a multifaceted tool with profound implications, promising advancements in our understanding of parasitic biology and shaping the development of future therapies.
Subject(s)
Babesia , Babesiosis , Disease Models, Animal , Erythrocytes , Animals , Babesia/drug effects , Babesia/genetics , Erythrocytes/parasitology , Mice , Babesiosis/drug therapy , Babesiosis/parasitology , Antiparasitic Agents/therapeutic use , Antiparasitic Agents/pharmacology , Humans , VirulenceABSTRACT
Emerging tick-borne illnesses, such as anaplasmosis, babesiosis, or ehrlichiosis, are caused by obligate intracellular pathogens that have clinically comparable presentations. Diagnostics used in laboratories today are serologic assays and blood smear analyses, which have known diagnostic limits. This study evaluated the performance of a sample-to-answer direct real-time PCR laboratory-developed test for the multiplex qualitative detection of Anaplasma, Babesia, and Ehrlichia DNA in whole-blood specimens. Compared to two standard-of-care (SOC) methods, the DiaSorin tick-borne laboratory-developed test for Anaplasma detection demonstrated a positive percent agreement (PPA) and negative percent agreement (NPA) of 100% (95% CI, 0.80 to 1.0) and 89% (95% CI, 0.74 to 0.97), respectively with a discordant rate of 9.3% against microscopy. After discordant resolution, the NPA increased to 100%. For Babesia, the test demonstrated a PPA of 100% (95% CI, 0.90 to 1.0) and NPA of 100% (95% CI, 0.90 to 1.0). Compared to a SOC PCR method Anaplasma samples showed a PPA of 100% (95% CI, 0.66 to 1.0) and NPA of 100% (95% CI, 0.90 to 1.0). Ehrlichia results showed a PPA of 100% (95% CI, 0.69 to 1.0) and NPA of 100% (95% CI, 0.90 to 1.0). The total percent agreement was 98% (95% CI, 0.95 to 0.99) with a κ statistic of 0.95 (95% CI, 0.90 to 0.99) or almost perfect agreement compared to SOC methods. This laboratory-developed test for detecting Anaplasma, Babesia, and Ehrlichia DNA provides rapid and reliable detection of tick-borne infections without nucleic acid extraction. IMPORTANCE: This work demonstrates that detection of tick-borne illnesses, such as anaplasmosis, babesiosis, or ehrlichiosis, can be performed directly from whole blood with no extraction. The assay described here has a high positive and negative percent agreement with existing methods and is used as the standard of care. An increasing incidence of tick-borne illness combined with shortage of well-trained technologists to perform traditional manual testing, testing options that can be adapted to various lab settings, are of the utmost importance.
Subject(s)
Anaplasma phagocytophilum , Anaplasmosis , Babesia , Babesiosis , Ehrlichia , Ehrlichiosis , Real-Time Polymerase Chain Reaction , Humans , Ehrlichia/isolation & purification , Ehrlichia/genetics , Anaplasma phagocytophilum/isolation & purification , Anaplasma phagocytophilum/genetics , Real-Time Polymerase Chain Reaction/methods , Ehrlichiosis/diagnosis , Ehrlichiosis/microbiology , Babesiosis/diagnosis , Babesiosis/parasitology , Babesiosis/blood , Babesia/isolation & purification , Babesia/genetics , Anaplasmosis/diagnosis , Anaplasmosis/microbiology , Sensitivity and Specificity , Tick-Borne Diseases/diagnosis , Tick-Borne Diseases/microbiology , Tick-Borne Diseases/parasitology , DNA, Bacterial/genetics , DNA, Bacterial/bloodABSTRACT
Gonadectomy in dogs is associated with changes in risks of a variety of non-infectious health conditions, but few studies have examined its effects on infectious disease outcomes. The objectives of our study were to estimate the causal effect of gonadectomy on the incidence rate of babesiosis diagnosis, and on the risk of severe babesiosis in diagnosed cases, in dogs 6 months and older seen at a veterinary academic hospital in South Africa from 2013 through 2020. To estimate the effect of gonadectomy on the incidence rate of babesiosis diagnosis in dogs, we conducted a case-control study with incidence density sampling of dogs seen through the hospital's primary care service, adjusting for sex, age, breed category and weight. We identified 811 cases and selected 3244 time-matched controls. To estimate the effect of gonadectomy on disease severity in dogs with babesiosis, we conducted a retrospective cohort study among all dogs with a diagnosis of babesiosis (n=923), including these 811 cases and a further 112 referred to the hospital, also adjusting for sex, age, breed category and weight. Gonadectomy substantially reduced the incidence rate of babesiosis (total effect incidence rate ratio [IRR] 0.5; 95â¯% confidence interval [CI] 0.41-0.60) and the risk of severe babesiosis among diagnosed dogs (total effect risk ratio [RR] 0.72; 95â¯% CI 0.60-0.86). Tipping point sensitivity analysis shows that these effect estimates are robust to unmeasured confounding bias. There was no evidence for modification of the effect of gonadectomy by sex, with effect estimates qualitatively similar for males and females for both outcomes. Compared to females, males had a higher incidence rate of babesiosis (IRR 1.74; 95â¯% CI 1.49-2.04) and a higher risk of severe disease (RR 1.12; 95â¯% CI 0.98-1.28). In conclusion, our study shows a robust protective effect of gonadectomy on the incidence and severity of babesiosis in both male and female dogs 6 months of age and older, and contributes important evidence to the debate on the overall risks and benefits of gonadectomy to dogs in this population.
Subject(s)
Babesiosis , Dog Diseases , Animals , Dogs , Dog Diseases/epidemiology , Dog Diseases/parasitology , Babesiosis/epidemiology , Babesiosis/parasitology , South Africa/epidemiology , Retrospective Studies , Case-Control Studies , Female , Male , Incidence , Hospitals, Animal , Orchiectomy/veterinary , Risk Factors , Cohort Studies , Ovariectomy/veterinaryABSTRACT
Piroplasm including Babesia spp. and Theileria spp. in cattle can cause illness that affects livestock productivity, resulting in significant production losses, especially in tropical and subtropical regions such as Thailand. This study aimed to investigate the prevalence of bovine piroplasms and to identify these blood parasites based on the 18S ribosomal RNA gene in cattle in the northeastern part of Thailand. Piroplasmid infections among beef and dairy cattle were examined using nested PCR. Furthermore, amplicon DNA was sequenced and analyzed, and a phylogenetic tree was constructed to determine the genetic diversity and relationships of the parasite in each area. A total of 141 out of 215 (65.6%) cattle were positive for infection with Babesia or Theileria. DNA analysis revealed that infection by Babesia bigemina, Babesia bovis, Theileria orientalis, Theileria sinensis, and Theileria sp. were common piroplasms in cattle in this region, with a high sequence shared identity and similarity with each other and clustered with isolates from other countries. This study provides information on the molecular epidemiology and genetic identification of Babesia spp. and Theileria spp. in beef and dairy cattle to provide a better understanding of piroplasm infection in cattle in this region, which will help control these blood parasites. Moreover, this is the first report identifying T. sinensis circulating among Thai cattle.
Subject(s)
Babesia , Babesiosis , Cattle Diseases , DNA, Protozoan , Phylogeny , RNA, Ribosomal, 18S , Theileria , Theileriasis , Animals , Cattle , Thailand/epidemiology , Theileria/genetics , Theileria/isolation & purification , Theileria/classification , Babesiosis/parasitology , Babesiosis/epidemiology , Theileriasis/epidemiology , Theileriasis/parasitology , Babesia/genetics , Babesia/classification , Babesia/isolation & purification , RNA, Ribosomal, 18S/genetics , DNA, Protozoan/genetics , Cattle Diseases/parasitology , Cattle Diseases/epidemiology , Prevalence , Sequence Analysis, DNA , Polymerase Chain Reaction , Genetic Variation , DNA, Ribosomal/genetics , DNA, Ribosomal/chemistry , Cluster AnalysisABSTRACT
Blood samples from fifteen captive Indian wolves (Canis lupus pallipes) maintained at Arignar Anna Zoological Park, Vandalur, Chennai were screened for the presence of Babesia spp., Ehrlichia canis and Trypnosoma evansi DNA by PCR. Out of 15 wolf samples, 3 samples were found positive for Babesia spp. The amplified 18S rRNA gene fragments from 3 wolves were sequenced and confirmed as Babesia gibsoni. A maximum likelihood tree was constructed using the three sequences along with other Babesia spp. sequences derived from GenBank adopting HKY nucleotide substitution model based on the Bayesian Information Criterion. The phylogenetic analysis confirmed that the three sequences were of Babesia gibsoni and highly divergent from Babesia canis, B. vogeli and B. vulpes. This might be a possible spill over event of B. gibsoni from community dogs through blood feeding dog ticks. This is the first report and molecular confirmation of B. gibsoni infection in captive Indian wolves.
Subject(s)
Babesia , Babesiosis , Phylogeny , RNA, Ribosomal, 18S , Wolves , Animals , Babesia/isolation & purification , Babesia/genetics , Babesia/classification , Babesiosis/parasitology , Babesiosis/epidemiology , India/epidemiology , Wolves/parasitology , RNA, Ribosomal, 18S/genetics , RNA, Ribosomal, 18S/analysis , Animals, Zoo , Polymerase Chain Reaction/veterinary , DNA, Protozoan/genetics , Female , MaleABSTRACT
BACKGROUND: Piroplasmosis is a common and prevalent tick-borne disease that affects equids. OBJECTIVES: To determine the infection and molecular characteristics of the piroplasms in donkeys from Xinjiang, northwestern China, we undertook a cross sectional study by collecting representative samples across several counties within the region. METHODS: A total of 344 blood samples were collected from adult domestic donkeys from 13 counties in Xinjiang. PCR was conducted to test for T. equi and B. caballi in the blood samples based on the equine merozoite antigen-1 (Ema-1) gene and the 48 kDa rhoptry protein (BC48) gene, respectively. RESULTS: Sixteen blood samples tested positive for piroplasms and the overall infection rate was 4.7% (16/344). Seven of the 13 counties were positive for piroplasms. Among the 16 piroplasm-positive samples, 15 were singly infected with T. equi with an infection rate of 4.4% (15/344), and coinfection with T. equi and B. caballi was detected in one sample (0.3%, 1/344) from Wushi. Four T. equi sequence genotypes were identified and grouped into different branches of the evolutionary trees. CONCLUSION: These findings suggest that the infection rate of piroplasms is low in domestic donkeys in southern Xinjiang and that T. equi genotypes have a regional distribution.
Subject(s)
Babesia , Babesiosis , Equidae , Theileria , Animals , Equidae/parasitology , China/epidemiology , Babesiosis/epidemiology , Babesiosis/parasitology , Babesia/isolation & purification , Babesia/genetics , Babesia/classification , Theileria/genetics , Theileria/isolation & purification , Cross-Sectional Studies , Female , Male , Prevalence , Theileriasis/epidemiology , Theileriasis/parasitologyABSTRACT
Babesia caballi is an intra-erythrocytic parasite causing equine piroplasmosis. Three B. caballi genotypes (A, B, and C) have been identified based on the 18â¯S rRNA and rhoptry-associated protein (rap-1) gene sequences. These variant parasite genotypes compromise the diagnostic utility of the WOAH-recommended serological assays in declaring horses free of equine piroplasmosis. Although a gene encoding a spherical body protein 4 (sbp4) has recently been identified as a potential antigen for the serological detection of B. caballi, the ability of this antigen to detect the different geographical strains has not been determined. The molecular distinction between variant B. caballi genotypes is limited and therefore we developed molecular typing assays for the rapid detection and quantification of distinct parasite genotypes. Field samples were screened for the presence of B. caballi using an established multiplex equine piroplasmosis qPCR assay. In this study, B. caballi genotype A was not detected in any field samples screened. However, phylogenetic analysis of the amplified sbp4 and 18â¯S rRNA genes confirmed the phylogenetic groupings of the South African isolates into either B. caballi genotypes B or C. A multiple sequence alignment of the sbp4 gene sequences obtained in this study together with the published sbp4 sequences representing B. caballi genotype A, were used to identify conserved regions within the gene to design three primer pairs and three genotype-specific TaqMan minor-groove binder (MGB™) probes. The qPCR assays were shown to be specific and efficient in the detection and differentiation between B. caballi genotypes A, B, and C and could be used as a diagnostic assay to prevent the unintentional spread of variant B. caballi genotypes globally.
Subject(s)
Babesia , Babesiosis , Genotype , Horse Diseases , Phylogeny , Babesia/genetics , Babesia/classification , Animals , Horses , Babesiosis/parasitology , Babesiosis/diagnosis , Horse Diseases/parasitology , Horse Diseases/diagnosis , RNA, Ribosomal, 18S/genetics , Protozoan Proteins/genetics , South Africa , DNA, Protozoan/geneticsABSTRACT
BACKGROUND: Bovine babesiosis is caused by infection with the protozoal parasite Babesia bovis, which is transmitted by Rhipicephalus (Boophilus) spp. It can cause mortality rates up to 90% in immunologically naive Bos taurus cattle. In south Texas, R. (B.) microplus is known to infest nilgai antelope (Boselaphus tragocamelus); however, their susceptibility to infection with B. bovis and their role in the transmission of the parasite remain unknown. In this study, we challenged nilgai antelope with B. bovis and evaluated their susceptibility to infection. METHODS: Nilgai were needle inoculated with ≈108 B. bovis-parasitized erythrocytes (merozoites) or a homogenate of B. bovis-infected larval ticks (sporozoite) delivered intravenously. Bos taurus beef calves were inoculated in parallel, as this strain of B. bovis is lethal to cattle. Temperature and hematocrit were monitored daily over the course of each study, and whole blood was collected for molecular [polymerase chain reaction (PCR)] and serological [indirect enzyme-linked immunosorbent assay (ELISA)] diagnostic evaluation. Histological sections of nilgai cerebral tissue were examined for evidence of infection. Recipient bovine calves were sub-inoculated with blood from nilgai challenged with either stage of the parasite, and they were monitored for clinical signs of infection and evaluated by a PCR diagnostic assay. Red blood cells (RBCs) from prechallenged nilgai and B. taurus beef cattle were cultured with an in vitro B. bovis merozoite culture to examine colonization of the RBCs by the parasite. RESULTS: Nilgai did not display clinical signs of infection upon inoculation with either the merozoite or sporozoite stage of B. bovis. All nilgai were PCR-negative for the parasite, and they did not develop antibodies to B. bovis. No evidence of infection was detected in histological sections of nilgai tissues, and in vitro culture analysis indicated that the nilgai RBCs were not colonized by B. bovis merozoites. Cattle subinoculated with blood from challenged nilgai did not display clinical signs of infection, and they were PCR-negative up to 45 days after transfer. CONCLUSIONS: Nilgai do not appear to be susceptible to infection with a strain of B. bovis that is lethal to cattle. Tick control on these alternative hosts remains a critical priority, especially given their potential to disseminate ticks over long distances.
Subject(s)
Antelopes , Babesia bovis , Babesiosis , Animals , Babesia bovis/genetics , Babesia bovis/pathogenicity , Babesia bovis/isolation & purification , Babesia bovis/immunology , Babesiosis/parasitology , Cattle , Antelopes/parasitology , Cattle Diseases/parasitology , Erythrocytes/parasitology , Texas , Virulence , Rhipicephalus/parasitology , Female , Polymerase Chain ReactionABSTRACT
Human babesiosis is a malaria-like illness caused by protozoan parasites of the genus Babesia. Babesia microti is responsible for most cases of human babesiosis in the United States, particularly in the Northeast and the Upper Midwest. Babesia microti is primarily transmitted to humans through the bite of infected deer ticks but also through the transfusion of blood components, particularly red blood cells. There is a high risk of severe and even fatal disease in immunocompromised patients. To date, serology testing relies on an indirect immunofluorescence assay that uses the whole Babesia microti antigen. Here, we report the construction of phage display cDNA libraries from Babesia microti-infected erythrocytes as well as human reticulocytes obtained from donors with hereditary hemochromatosis. Plasma samples were obtained from patients who were or had been infected with Babesia microti. The non-specific antibody reactivity of these plasma samples was minimized by pre-exposure to the human reticulocyte library. Using this novel experimental strategy, immunoreactive segments were identified in three Babesia microti antigens termed BmSA1 (also called BMN1-9; BmGPI12), BMN1-20 (BMN1-17; Bm32), and BM4.12 (N1-15). Moreover, our findings indicate that the major immunoreactive segment of BmSA1 does not overlap with the segment that mediates BmSA1 binding to mature erythrocytes. When used in combination, the three immunoreactive segments form the basis of a sensitive and comprehensive diagnostic immunoassay for human babesiosis, with implications for vaccine development.
Subject(s)
Antigens, Protozoan , Babesia microti , Babesiosis , Gene Library , Babesia microti/immunology , Babesia microti/genetics , Humans , Antigens, Protozoan/immunology , Antigens, Protozoan/genetics , Babesiosis/immunology , Babesiosis/parasitology , Antibodies, Protozoan/immunology , Antibodies, Protozoan/blood , Erythrocytes/parasitology , Erythrocytes/immunology , Cell Surface Display Techniques , AnimalsABSTRACT
The currently accepted initiation of Babesia infection describes a sporozoite stage infused into the host, along with other saliva components, by the tick vector. This sporozoite can enter and initiate erythrocyte infection directly. In the particular case of Babesia microti, however, that sporozoite loses the ability to further propagate in vitro once deprived of its natural host. True B. sensu stricto do not require the host collaboration described in this study. Hence it has become a current topic of research involving B. microti (B. sensu lato), a rather unique species that requires host collaboration to maintain an erythrocyte propagation cycle. The main attachment protein is synthesized by this parasite in excess and exported to the host from the erythrocyte infrastructure to immunize the host at all stages of infection. The synthesis of host immune IgM antibody is necessary for the propagation of B. microti, being central to entry into uninfected host erythrocytes. Sequential use of the host immune system then involves complement factor C3b to complete the three-part assembly necessary to initiate the rhoptry sequence for invasion of uninfected erythrocytes and further propagation. These several components must be furnished within the in vitro culture medium and the sequence of these reactions is discussed. The corollary view of the parasite survival versus the host immune defenses is also discussed as it involves the same host factors promoting continuing parasite growth. This is the first description of continuous in vitro propagation of B. microti.
Subject(s)
Babesia microti , Erythrocytes , Animals , Humans , Babesia microti/immunology , Babesiosis/parasitology , Babesiosis/immunology , Erythrocytes/parasitology , Host-Parasite InteractionsABSTRACT
Ticks parasitize various hosts, including humans, and are known to transmit pathogens that can be harmful not only to animals but also to humans. To evaluate the possible presence of pathogens in ticks, we aimed to collect and identify tick fauna specimens in Lagoa Comprida Municipal Natural Park, an anthropogenic urban area located in Aquidauana, Mato Grosso do Sul, Brazil. A total of 1216 ticks, of which 51.2% were Amblyomma sculptum, 1.2% were Amblyomma dubitatum, and 41% were Amblyomma spp. were collected. These results show that the prevalence of A. sculptum is significantly higher than that of A. dubitatum across all four seasons. Molecular analyses revealed positive samples for the genus Babesia, including the confirmation of Babesia bigemina in an A. sculptum specimen, marking the first record of this relationship. This unexpected finding demands greater attention and deeper analysis in the context of the epidemiology of tick-borne diseases.