Genetic diversity of Babesia bovis studied longitudinally under natural transmission conditions in calves in the state of Rio de Janeiro, Brazil / Diversidade genética de Babesia bovis estudada longitudinalmente em condições de transmissão natural entre bezerros no estado do Rio de Janeiro, Brasil

Abstract Serum and DNA samples from 15 naturally infected calves in Seropédica, Brazil, were obtained quarterly from birth to 12 months of age, in order to longitudinally evaluate their humoral immune response against Babesia bovis and the merozoite surface antigen diversity of B. bovis. Anti-B. bovis IgG antibodies were detected by an indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA). Using DNA amplification, sequencing and phylogenetic analysis, the genetic diversity of B. bovis was assessed based on the genes that encode merozoite surface antigens (MSA-1, MSA-2b and MSA-2c). The serological results demonstrated that up to six months of age, all the calves developed active immunity against B. bovis. Among the 75 DNA samples evaluated, 0, 3 and 5 sequences of the msa-1, msa-2b and msa-2c genes were obtained, respectively. The present study demonstrated that the msa-2b and msa-2c gene sequences amplified from blood DNA of B. bovis-positive calves were genetically diversified. These data emphasize the importance of conducting deeper studies on the genetic diversity of B. bovis in Brazil, in order to design diagnostic antigens and vaccines in the future.

Resumo Para avaliar longitudinalmente a resposta imune humoral anti-B. bovis e a diversidade genética de antígenos de superfície de merozoítos de B. bovis, entre bezerros naturalmente infectados em Seropédica, Brasil, amostras de soro e DNA de 15 bezerros foram obtidas trimestralmente, desde o nascimento até 12 meses de idade. Anticorpos IgG para B. bovis foram detectados pelos testes de Imunofluorescência Indireta e Ensaio de Imunoadsorção Enzimático Indireto. Usando-se amplificação de DNA, sequenciamento e análises filogenéticas, a diversidade genética de B. bovis, com base nos genes que codificam antígenos de superfície de merozoítos (MSA-1, MSA-2b e MSA-2c) foi investigada. Os resultados da sorologia demonstraram que, até os seis meses de idade, todos os bezerros desenvolveram imunidade ativa contra B. bovis. Entre as 75 amostras de DNA avaliadas, foram obtidas 0, 3 e 5 sequências dos genes msa-1, msa-2b e msa-2c. O presente estudo demonstrou que sequências dos genes msa-2b e msa-2c amplificadas a partir de amostras de sangue positivas para B. bovis de bezerros de Seropédica, foram geneticamente distintas. O presente trabalho realça a importância de se realizar estudos aprofundados sobre a diversidade genética de B. bovis no Brasil, objetivando o desenvolvimento de antígenos para o diagnóstico e vacinas no futuro.

Molecular detection of vector-borne agents in cats in Southern Brazil / Detecção molecular de agentes transmitidos por vetores em felinos domésticos no Sul do Brasil

Abstract This study used serological and molecular methods to investigate the occurrence of vector-borne pathogens (VBP) with zoonotic potential in cats neutered at the University Veterinary Hospital in Canoinhas, Santa Catarina. The combined PCR and serological results revealed that 17 (56.6%) cats were positive for one or more pathogens. The sampled cats had antibodies to Ehrlichia spp. (7/30), Anaplasma phagocytophilum (3/30) and Leishmania infantum (2/30). The PCR assay detected DNA closely related to Ehrlichia canis in 6/30 cats, Mycoplasma haemofelis in 2/30 cats, A. phagocytophilum and Cytauxzoon sp. in one cat each. While Bartonella clarridgeiae and B. henselae were detected in two cats each, and B. koehlerae was detected in one cat.

Resumo Como os felinos podem ser parasitados por diversos patógenos transmitidos por vetores (PTV), alguns com caráter zoonótico, este estudo objetivou detectar por métodos sorológicos e moleculares, patógenos transmitidos por vetores hematófagos, em gatos atendidos em um Hospital Veterinário Universitário em Santa Catarina. Os resultados da PCR e da sorologia combinados, revelaram que 17 (56,6%) gatos foram positivos para um ou mais patógenos. Na sorologia, foram positivos 7/30 gatos para Ehrlichia, 3/30 para Anaplasma phagocytophilum e 2/30 para Leishmania infantum. Na PCR foi detectado DNA filogeneticamente associado a: Ehrlichia canis em 6/30 gatos; Mycoplasma haemofelis, em 2/30 gatos; A. phagocytophilum e Cytauxzoon sp. em 1/30 gatos cada. Enquanto Bartonella clarridgeiae e B. henselae foram detectadas, cada uma, em dois gatos, B. koehlerae foi detectada em um gato.

Cathepsin L-a novel cysteine protease from Haemaphysalis flava Neumann, 1897.

Ixodid ticks are ectoparasites responsible for the transmission of a large number of bacterial, viral, and protozoan pathogens to animals and humans. As long-term blood-pool feeders, the digestion of host blood is critical to their development as well as to the establishment of the sexual cycle of hemoparasites such as Babesia parasites, the agents of human and animal babesiosis. Previous studies have demonstrated that cysteine proteases are involved in blood digestion, embryogenesis, and pathogen transmission in other species of ticks, but their characteristics and functions are still unidentified in Haemaphysalis flava. Here, we describe the characterization of a cysteine protease HfCL from H. flava. We show that HfCL belongs to the L-like papain family of proteases, exhibits high expression in nymphs and adults, and localizes to both the midgut and salivary glands. Biochemical assays using purified recombinant enzyme reveal that rHfCL can hydrolyze the fluorogenic substrate Z-phe-Arg-MCA with optimal activity detected at pH 6. Furthermore, the short-term growth assay indicates that rHfCL can inhibit the intraerythrocytic development of Babesia microti and Babesia gibsoni in vitro.

Dynamics of natural infection by Babesia bovis and Babesia bigemina in dairy cattle from an enzootic instability area in Northeastern Brazil / Dinâmica da infecção natural por Babesia bovis e Babesia bigemina em bovinos leiteiros de uma área de instabilidade enzoótica no Nordeste do Brasil

Abstract This study aimed to determine the dynamics of natural infection in the transmission of Babesia spp. to cattle in an enzootic instability area in Northeastern Brazil. Blood samples were collected from 30 calves located on two dairy farms to determine the packed cell volume (PCV) and the timing of the primo-infection using polymerase chain reaction (PCR) and their association with climatic factors and management practices. On Farm A, the determination of primo-infection was observed on average at 249.4 (±24.42) days of age for B. bigemina and at 252.6 (±17.07) days of age for B. bovis; there was no significant difference between the times of infection (P> 0.05). The infection coincided with a period of high rainfall in the region. On Farm B, primo-infection infection was not observed. There was no infection by Babesia spp. on Farm B due to the intensive use of acaricides that led to an absence of ticks. There was no significant difference between the average PCV of animals from Farms A and B (P> 0.05). The management practices on the properties, in addition to the weather conditions influenced the exposure of the animals to disease vectors and may have contributed to the maintenance of this enzootic area in Northeastern Brazil.

Resumo Este estudo teve como objetivo determinar a dinâmica da infecção natural na transmissão de Babesia spp. em bovinos de uma área de instabilidade enzoótica no Nordeste do Brasil. Foram coletadas amostras de sangue de 30 bezerras, proveniente de duas propriedades leiteiras para determinação do volume globular e da primo-infecção por meio da reação em cadeia da polimerase associando aos fatores climáticos e medidas de manejo. Na fazenda A, o período médio da primo-infecção para B. bigemina, determinado por meio da PCR, foi de 249,4 (±24,42) dias de idade, enquanto que para B. bovis foi aos 252,6 (±17,07) dias de idade, não existindo diferença estatística. A infecção coincidiu com o período de alta precipitação pluviométrica na região. Não houve infecção por Babesia spp. na fazenda B, na qual o uso intensivo de acaricidas determinou ausência de carrapatos. Não houve diferença significativa entre médias de VG dos animais das fazendas A e B. O manejo adotado nas fazendas estudadas, associado às condições climáticas, interferem na exposição dos animais aos vetores, podendo favorecer a manutenção de uma área de instabilidade enzoótica no Nordeste do Brasil.

Transfusion-transmitted babesiosis leading to severe hemolysis in two patients with sickle cell anemia.

The intracellular parasites Babesia microti and Babesia duncani can be transmitted by blood transfusion and cause severe life-threatening hemolytic anemia in high-risk patients, including those with sickle cell disease. The rarity of the diagnosis, as well as its similar clinical presentation to delayed hemolytic transfusion reaction, may lead to a delay in diagnosis, as well as inappropriate treatment with steroids or other immunosuppressive agents. The morbidity caused by this disease in especially vulnerable populations justifies the need for a universal blood-screening program in endemic areas.

Inactivation of Babesia microti in red blood cells and platelet concentrates.

BACKGROUND: With an increasing number of recognized transfusion-transmitted (TT) babesiosis cases, Babesia microti is the most frequently TT parasite in the United States. We evaluated the inactivation of B. microti in red blood cells (RBCs) prepared in Optisol (AS-5) using amustaline and glutathione (GSH) and in platelet components (PCs) in 100% plasma using amotosalen and low-energy ultraviolet A (UVA) light. STUDY DESIGN AND METHODS: Individual RBCs and apheresis PCs were spiked with B. microti-infected hamster RBCs (iRBCs) to a final concentration of 106 iRBCs/mL and treated with the respective inactivation systems according to the manufacturer's instruction. Samples were collected before (control) and after (test) each treatment. Dilutions of the control samples to 10-6 were inoculated into hamsters, while the test samples were inoculated neat or at 10-1 dilution. At 3 and 5 weeks postinoculation, hamsters were evaluated for B. microti infection by microscopic observation of blood smears and 50% infectivity titers (ID50 ) were determined. Log reduction was calculated as control log ID50 minus test log ID50 . RESULTS: Parasitemia was detected in hamsters injected with as low as 100,000-fold diluted control samples, while no parasites were detectable in the blood smears of any hamsters receiving neat test samples. Mean log reduction was more than 5 log/mL by amustaline/GSH for RBCs and more than 4.5 log/mL by amotosalen/UVA for PCs. CONCLUSION: B. microti was inactivated to the limit of detection in RBCs and PCs after the respective inactivation treatment. Complete inactivation of B. microti was achieved in this animal infectivity model, and pathogen reduction treatment inhibited transmission of infection.

Cases of transfusion-transmitted babesiosis occurring in nonendemic areas: a diagnostic dilemma.

BACKGROUND: Transfusion-transmitted babesiosis (TTB) has been rapidly increasing in incidence since the beginning of the 21st century. Asymptomatic individuals with Babesia infection are able to donate blood in the United States because of the lack of specific blood donation testing. Blood products collected in Babesia-endemic areas are distributed nationally; thus, clinicians in nonendemic states may fail to include babesiosis in the differential diagnosis of a patient who had a recent transfusion history and a fever of unknown origin. STUDY DESIGN AND METHODS: We report the details of two cases of clinical transfusion-transmitted babesiosis and one asymptomatic infection identified in red blood cell recipients in two nonendemic states (South Carolina and Maryland), which, when combined with three recent additional cases in nonendemic states, totals six recipient infections in three nonendemic states. RESULTS: Delayed diagnosis of transfusion-transmitted babesiosis places patients at risk for increased morbidity and mortality and may result in clinical mismanagement or unnecessary treatments. A peripheral blood smear should be reviewed in any patient with a recent transfusion and a fever of unknown origin. Prompt communication of the diagnosis among physicians is key to ensuring that patients with transfusion-transmitted babesiosis are treated expeditiously, and a transfusion service investigation is necessary to identify additional recipients from the same donor. CONCLUSION: TTB is appearing in traditionally nonendemic states because of blood product distribution patterns. Clinicians should include TTB on the differential diagnosis in any patient presenting who had a recent transfusion history and a fever of unknown origin, regardless of where the transfusion took place.

Screening for Babesia microti in the U.S. Blood Supply.

BACKGROUND: Babesia microti, a tickborne intraerythrocytic parasite that can be transmitted by means of blood transfusion, is responsible for the majority of cases of transfusion-transmitted babesiosis in the United States. However, no licensed test exists for screening for B. microti in donated blood. We assessed data from a large-scale, investigational product-release screening and donor follow-up program. METHODS: From June 2012 through September 2014, we performed arrayed fluorescence immunoassays (AFIAs) for B. microti antibodies and real-time polymerase-chain-reaction (PCR) assays for B. microti DNA on blood-donation samples obtained in Connecticut, Massachusetts, Minnesota, and Wisconsin. We determined parasite loads with the use of quantitative PCR testing and assessed infectivity by means of the inoculation of hamsters and the subsequent examination for parasitemia. Donors with test-reactive samples were followed. Using data on cases of transfusion-transmitted babesiosis, we compared the proportions of screened versus unscreened donations that were infectious. RESULTS: Of 89,153 blood-donation samples tested, 335 (0.38%) were confirmed to be positive, of which 67 (20%) were PCR-positive; 9 samples were antibody-negative (i.e., 1 antibody-negative sample per 9906 screened samples), representing 13% of all PCR-positive samples. PCR-positive samples were identified all through the year; antibody-negative infections occurred from June through September. Approximately one third of the red-cell samples from PCR-positive or high-titer AFIA-positive donations infected hamsters. Follow-up showed DNA clearance in 86% of the donors but antibody seroreversion in 8% after 1 year. In Connecticut and Massachusetts, no reported cases of transfusion-transmitted babesiosis were associated with screened donations (i.e., 0 cases per 75,331 screened donations), as compared with 14 cases per 253,031 unscreened donations (i.e., 1 case per 18,074 unscreened donations) (odds ratio, 8.6; 95% confidence interval, 0.51 to 144; P=0.05). Overall, 29 cases of transfusion-transmitted babesiosis were linked to blood from infected donors, including blood obtained from 10 donors whose samples tested positive on the PCR assay 2 to 7 months after the implicated donation. CONCLUSIONS: Blood-donation screening for antibodies to and DNA from B. microti was associated with a decrease in the risk of transfusion-transmitted babesiosis. (Funded by the American Red Cross and Imugen; ClinicalTrials.gov number, NCT01528449 .).

Transfusion-transmitted babesiosis: is it time to screen the blood supply?

PURPOSE OF REVIEW: This review summarizes the current status of blood screening to prevent transfusion-transmitted babesiosis (TTB). RECENT FINDINGS: Babesia microti has recently been determined to be the most common transfusion-transmitted pathogen in the United States. Patients who acquire TTB often experience severe illness with an associated mortality rate of about 20%. Recent studies have demonstrated that laboratory screening using B. microti antibody and/or PCR assays can effectively identify infectious blood donors and that this approach may offer a cost- effective means of intervention. Pathogen inactivation methods may offer an alternative solution. None of these methods has yet been licensed by US Food and Drug Administration, however, and current efforts to prevent TTB rely on excluding blood donors who report having had babesiosis. SUMMARY: TTB imposes a significant health burden on the United States population. Further research is needed to better inform decisions on optimal screening strategies and reentry criteria, but given the acute need and the currently available screening tools, initiation of blood donor screening to prevent TTB should be given high priority.

Molecular assays reveal the presence of Theileria spp. and Babesia spp. in Asian water buffaloes (Bubalus bubalis, Linnaeus, 1758) in the Amazon region of Brazil.

Approximately 50% of buffalo herds in Brazil are located in Pará state in northern Brazil. There are several properties where cattle and buffalo live and graze together, and thus, buffalo pathogens may threaten the health of cattle and vice versa. Therefore, knowledge of infectious agents of buffalo is essential for maintaining healthy livestock. Clinical disease caused by Theileria and Babesia parasites in the Asian water buffalo is not common, although these animals may act as reservoir hosts, and the detection of these hemoparasites in buffaloes is as important as it is in cattle. Studies of the infection of buffaloes by hemoparasites in Brazil are scarce. The objective of the present study was to investigate the occurrence of Piroplasmida parasites in Asian water buffaloes in the state of Pará in the Amazon region of Brazil using nested PCR assays and phylogenetic analysis. The 18S rRNA gene and ITS complete region were amplified from DNA extracted from blood samples collected from 308 apparently healthy buffaloes bred on six properties in the state of Pará, Brazil. The prevalence of positive buffalo samples was 4.2% (13/308) for Theileria spp., 3.6% (11/308) for Babesia bovis and 1% (3/308) for Babesia bigemina. Animals infected with Theileria were detected in 50% (3/6) of the assessed properties. Phylogenetic analyses indicated that the Theileria species detected in this study were closely related to Theileria buffeli, Theileria orientalis and Theileria sinensis. To our knowledge, this is the first report of Theileria in Asian water buffaloes in the Americas. The majority of Theileria-positive buffaloes (11/13) belong to a property that has a history of animals presenting lymphoproliferative disease of unknown etiology. Therefore, the present research suggests that this disorder can be associated with Theileria infection in this property. Our results provide new insights on the distribution and biological aspects of hemoparasites transmissible from buffaloes to cattle.

[Human babesiosis - a rare but potentially dangerous zoonosis]. / Humane Babesiose - eine seltene, aber potenziell gefährliche Zoonose.

Human babesiosis is caused by the intraerythrocytic parasite of the genus Babesia (phylum Apicomplexa). Humans are commonly infected by the bite of Ixodid ticks. Rarely, transmission does occur perinatal or via contaminated blood transfusion. There is only insufficient data available on the clinical relevance in Europe, whereas there are known endemic states in the United States with an increasing importance of the disease in transfusion medicine. The following article gives an overview of the situation in Germany. Human babesiosis is a zoonotic disease with a worldwide increasing importance according to the increasing number of immunocompromised patients. Clinical symptoms have a wide range from asymptomatic to severe and letal cases. So far, the detection of the parasites in ticks and seroepidemiological data in Europe identified 3 humanpathogenic species: B. microti, B. divergens und B. venatorum (EU1-3). The relative small number of approximately 50 documented human cases is probably due to the lack of knowledge of the disease and the availability of diagnostic tools. Comprehensive systematic investigations of the prevalence in ticks, seroepidemiological data and improved diagnostic tests are urgently needed to evaluate the importance of the parasite.

Riboflavin and ultraviolet light reduce the infectivity of Babesia microti in whole blood.

BACKGROUND: Babesia microti is the parasite most frequently transmitted by blood transfusion in the United States. Previous work demonstrated the efficacy of riboflavin (RB) and ultraviolet (UV) light to inactivate B.microti in apheresis plasma and platelet units. In this study we investigated the effectiveness of RB and UV light to reduce the levels of B.microti in whole blood (WB). STUDY DESIGN AND METHODS: WB units were spiked with B. microti-infected hamster blood. Spearman-Karber methods were used to calculate infectivity of each sample in terms of hamster infectious dose 50% (HID50 ) value. After RB addition, the units were illuminated with 80 J/mLRBC UV light. Two samples were collected: one before illumination and one after illumination. The samples were serially diluted and dilutions injected into a group of five naive hamsters. Four weeks postinoculation (PI), blood was collected from the animals and evaluated by microscopic observation. RESULTS: One pilot study showed a good dose response in the animals and demonstrated that sample infectivity could be calculated in terms of an HID50 . Three additional replicates were performed in the same manner as the pilot study, but with fewer dilutions. Infectivity values were consistent between the experiments and were used to calculate log reduction. The posttreatment reduction of B. microti for all the experiments was more than 5 log. CONCLUSIONS: The data collected indicate that use of RB and UV is able to decrease the parasite load in WB units thus reducing the risk of transfusion-transmitted B. microti from blood components containing B. microti-infected RBCs.

Transfusion-transmitted babesiosis in an immunocompromised patient: a case report and review.

Babesiosis is a tick- and transfusion-borne disease caused by intraerythrocytic Babesia parasites. In 2009, a 61-year-old Minnesota woman with chronic lymphocytic leukemia and a history of recent chemotherapy and numerous blood transfusions for gastrointestinal bleeding became febrile and anemic 12 days postsplenectomy. Babesia were visualized on blood smears, confirmed by polymerase chain reaction as B. microti. She developed respiratory failure despite initiation of clindamycin and quinine, and required 12 weeks of azithromycin and atovaquone before blood smear and polymerase chain reaction findings were negative. Serologic evidence of B. microti infection was identified in 1 associated blood donor and 1 other recipient of that donor's blood. Babesia infection can be asymptomatic or cause mild to fulminant disease resulting in multiorgan failure or death. Patients with advanced age, asplenia, or other immune compromise are at risk for severe babesiosis and may require prolonged treatment to eradicate parasitemia. Incidence of transfusion-transmitted babesiosis has increased over the past decade.

Tick vitellogenin receptor reveals critical role in oocyte development and transovarial transmission of Babesia parasite.

A cDNA encoding the vitellogenin receptor of the ixodid tick, Haemaphysalis longicornis Neumann (HlVgR) was cloned and characterized. The full-length cDNA is 5631 bp, including an intact ORF encoding an expected protein with 1782 amino acids. The deduced amino acid sequence of the HlVgR cDNA revealed two ligand-binding domains with four class A cysteine-rich repeats in the first domain and eight in the second domain similar to those of insect VgRs. The immunoblot analysis detected approximately 197 kDa protein in both tick ovary and egg. The developmental expression profile demonstrated that HlVgR mRNA exists throughout the ovarian development, and the transcriptional level is especially high in the previtellogenic period. Immuno electron microscopy analysis demonstrated that the localization of HlVgR is detected on the external surface of oocyte plasma membrane. RNAi showed that eggs of HlVgR dsRNA-injected adult ticks had not developed into fully mature oocytes and laid abnormal eggs. The Babesia parasite DNA was not detected in the eggs of HlVgR dsRNA-injected tick that fed on Babesia gibsoni infected dog, whereas it was detected in the eggs of PBS-injected ticks and noninjected ticks. Expression of HlVgR was increased by the vitellogenic hormone 20-hydroxyecdysone. These results indicate that HlVgR, which is produced by the developing oocytes, is essential for Vg uptake, egg development in the H. longicornis tick, and transovarial transmission of Babesia parasites.

A cysteine protease is critical for Babesia spp. transmission in Haemaphysalis ticks.

Vector ticks possess a unique system that enables them to digest large amounts of host blood and to transmit various animal and human pathogens, suggesting the existence of evolutionally acquired proteolytic mechanisms. We report here the molecular and reverse genetic characterization of a multifunctional cysteine protease, longipain, from the babesial parasite vector tick Haemaphysalis longicornis. Longipain shares structural similarity with papain-family cysteine proteases obtained from invertebrates and vertebrates. Endogenous longipain was mainly expressed in the midgut epithelium and was specifically localized at lysosomal vacuoles and possibly released into the lumen. Its expression was up-regulated by host blood feeding. Enzymatic functional assays using in vitro and in vivo substrates revealed that longipain hydrolysis occurs over a broad range of pH and temperature. Haemoparasiticidal assays showed that longipain dose-dependently killed tick-borne Babesia parasites, and its babesiacidal effect occurred via specific adherence to the parasite membranes. Disruption of endogenous longipain by RNA interference revealed that longipain is involved in the digestion of the host blood meal. In addition, the knockdown ticks contained an increased number of parasites, suggesting that longipain exerts a killing effect against the midgut-stage Babesia parasites in ticks. Our results suggest that longipain is essential for tick survival, and may have a role in controlling the transmission of tick-transmittable Babesia parasites.

Photochemical inactivation with amotosalen and long-wavelength ultraviolet light of Plasmodium and Babesia in platelet and plasma components.

BACKGROUND: Transfusion-transmitted cases of malaria and babesiosis have been well documented. Current efforts to screen out contaminated blood products result in component wastage due to the lack of specific detection methods while donor deferral does not always guarantee safe blood products. This study evaluated the efficacy of a photochemical treatment (PCT) method with amotosalen and long-wavelength ultraviolet light (UVA) to inactivate these agents in red blood cells (RBCs) contaminating platelet (PLT) and plasma components. STUDY DESIGN AND METHODS: Plasmodium falciparum- and Babesia microti-contaminated RBCs seeded into PLT and plasma components were treated with 150 micromol per L amotosalen and 3 J per cm2 UVA. The viability of both pathogens before and after treatment was measured with infectivity assays. Treatment with 150 micromol per L amotosalen and 1 J per cm2 UVA was used to assess the robustness of the PCT system. RESULTS: No viable B. microti was detected in PLTs or plasma after treatment with 150 mol per L amotosalen and 3 J per cm2 UVA, demonstrating a mean inactivation of greater than 5.3 log in PLTs and greater than 5.3 log in plasma. After the same treatment, viable P. falciparum was either absent or below the limit of quantification in three of four replicate experiments both in PLTs and in plasma demonstrating a mean inactivation of at least 6.0 log in PLTs and at least 6.9 log in plasma. Reducing UVA dose to 1 J per cm2 did not significantly affect the level of inactivation. CONCLUSION: P. falciparum and B. microti were highly sensitive to inactivation by PCT. Pathogen inactivation approaches could reduce the risk of transfusion-transmitted parasitic infections and avoid unnecessary donor exclusions.

[Babesiosis of human and domestic dog; ethiology, pathogenesis, diagnostics]. / Babeszjoza czlowieka i psa domowego; etiologia, chorobo- twórczosc, diagnostyka.

This article presents the current state of our knowledge on babesiosis (piroplasmosis), one of the dangerous, invasive disease of humans and animals, transmitted by ticks. It is included among emerging diseases because its spread and significance have increased in recent years. This sickness is caused by intraerythrocytic parasites belonging to the Babesia species and it is a well-known zoonosis occurring in animals; as a human disease it was unknown almost till the first half of the last century. The intensified migration of human population and human interference in a forest biotope caused that number of recognized cases has grown considerably in recent years. Piroplasmosis in dogs is widely spread all over the world and it is caused by several Babesia species. The principal etiological factor of babesiosis in dogs is B. canis, which turned out to be a collective species represented by three subspecies for which the vectors are three different species of ticks. Their geographical extent indicates the endemic areas for this often fatal disease. A technique, the most often applied in the detection of Babesia is a full blood smear stained with Giemsa or Wright method. However, the estimation of the specimen depends to a large extent on the experience of the diagnostician. The immunological and serological methods are characterized with a high specificity and sensitivity but there are patients in which the false negative results have been obtained. Therefore, the traditional methods have been complemented or even ousted by the molecular methods, in which polymerase chain reaction (PCR) brings the biggest profits. However, the standardization of this technique still remains under elaboration. The usefulness of the PCR protocol has been tested with different molecular destinations from which sequences of genes encoding rRNA for small ribosomal subunit are taken into consideration. Within ribosome, the evolutionally conservative areas can be distinguished, i.e. having the nucleotide sequences similar to the majority or all Babesia species and to others closely related to them. Such construction of gene enables designing of starters complementary to conservative sites to PCR, detecting a large group of related organisms. Another molecular marker allowing on the accurate identification of Babesia is gene encoding the beta-tubuline protein. There are two introns within this gene, from which the first one shows a big variability with regard to the length as well as to the nucleotide sequence, therefore, the PCR products show a diverse length depending on the Babesia species. But these differences are too small for some species and, confirming methods that extend time of diagnostics are essential. The other genes which sequences can be used as molecular aim to the detection of DNA and Babesia species diversification are genes encoding the Heat Shock Proteins HSP 70. However, the gene hsp 70 shows a big conservatism of the nucleotide sequence even between the non related organisms; therefore, this method, based on the amplification of whole genome or its fragments, applies mainly in analysis of molecular phylogenetic.

Infection and blood transfusion: a guide to donor screening.

In recent years, blood-component therapy has become more accessible in veterinary practice. As with human medicine, care must be taken to minimize the risk of disease transmission from donor to recipient. Determining the appropriate diseases to screen for is complicated by regional variations in disease incidence, the existence of chronic carrier states for some diseases, the difficulty in screening-test selection, and testing cost. The feline diseases considered include retroviral infections, feline coronaviruses, ehrlichiosis (Ehrlichia canis-like), anaplasmosis (Anaplasma phagocytophilum), neorickettsiosis (Neorickettsia risticii), hemoplasmosis (Mycoplasma hemofelis and M. hemominutum, previously feline hemobartonellosis), and cytauxzoonosis (Cytauxzoon felis). The canine diseases considered in this paper include babesiosis (Babesia canis and B. gibsonii,) ehrlichiosis (E. canis and E. ewingii), anaplasmosis (A. phagocytophilum), neorickettsiosis (N. risticii var. atypicalis), leishmaniasis (Leishmania donovani complex), brucellosis (Brucella canis), hemoplasmosis (M. hemocanis, previously canine hemobartonellosis), and bartonellosis (Bartonella vinsonii).

Prevalência de anticorpos antiBabesia equi em eqüinos no Planalto Catarinense / Prevalence of Babesia equi antibodies in horses in the Santa Catarina Plateau, Brazil

Para avaliar a prevalência de anticorpos antiBabesia equi, através da técnica de imunofluorescência indireta (IFI), foram examinados 397 amostras de soro. As amostras de sangue, para obtençäo dos soros, foram coletadas de eqüinos de diferentes idades, raças, sexos, nascidos e criados no Planalto Catarinense, dos municípios de Lages, Säo Joaquim, Bom Jardim da Serra, Campos Novos, Anita Garibaldi, Curitibanos e Correia Pinto. Os resultados obtidos indicaram a existência de 50,38 por cento de animais sorologicamente reativos para B. equi, na diluiçäo de 1:40. Entre os municípios, os percentuais de animais soropositivos variaram de 18,51 por cento a 64,70 por cento.