Babesiose cerebral em bezerros / Cerebral babesiosis in calves

Babesiose cerebral é uma enfermidade causada pelo protozoário Babesia bovis. O agente faz parte do complexo Tristeza Parasitária Bovina, uma das mais importantes doenças parasitárias em bovinos. O presente estudo relata um surto causado por B. bovis em vinte bezerros de aproximadamente 7 a 25 dias de idade. O surto ocorreu entre março e junho de 2015, na região sul do Brasil, área de instabilidade enzoótica para a Tristeza Parasitária Bovina. O diagnóstico foi realizado pela epidemiologia, lesões macroscópicas e pela presença de numerosas formas parasitárias de Babesia bovis em capilares encefálicos, observados em imprints corados por Giemsa. Surtos de babesiose por B. bovis cerebral nos primeiros dias de vida de bezerros é incomum, porém não pode ser desconsiderada em surtos com alta letalidade em áreas de instabilidade enzoótica.(AU)

Cerebral babesiosis is a protozoan disease caused by Babesia bovis. This parasite belongs to the bovine parasitic complex of tick-borne diseases that affect livestock worldwide. The present study reports an outbreak caused by B. bovis affected twenty 7-25 day-old calves. Outbreak occurred from May to July 2015 in the south of Brazil, where there is an area of enzootic instability for cattle tick fever. The macroscopic lesions were anemia, hemoglobinuria, splenomegaly, hepatomegaly, yellow liver and cherry-pink discoloration of cerebral and cerebellar cortex. The diagnosis was based on epidemiology, necropsy and microscopic findings in the brain that showed B. bovis in the capillary vessels of the brain in imprints stained by Giemsa. Cases of cerebral babesiosis by Babesia bovis in such young calves are uncommon but should be considered as a diagnosis possibility when there is high mortality rate in areas ofen zootic instability.(AU)

Caracterização histoquímica no diagnóstico da babesiose bovina por Babesia bovis / Histochemical characterization in the diagnosis of bovine babesiosis by Babesia bovis

A babesiose é uma doença hemolítica transmitida por carrapatos e causada por protozoários intraeritrocitários do gênero Babesia. Esta é uma doença de incidência elevada na Região Sul do Brasil e responsável por perdas econômicas consideráveis. O diagnóstico clínico-patológico pode ser feito através da demonstração do parasito pelo exame de esfregaços sanguíneos ou de tecidos frescos. Entretanto, com frequência, somente órgãos fixados em formol são remetidos para laboratórios de patologia, o que impossibilita a realização do esfregaço. O principal objetivo deste estudo foi encontrar técnicas histoquímicas alternativas e capazes de aprimorar a evidenciação de Babesia bovis intraeritrocitária em tecidos fixados em formol. Para este estudo, foram analisadas retrospectivamente amostras de tecidos de 50 casos de necropsias de bovinos, as quais haviam sido fixadas em formol e processadas rotineiramente para histopatologia. Os casos foram divididos em um grupo controle, constituído por 12 casos de babesiose cerebral com substância cinzenta encefálica róseo-cereja característica (grupo A), e 38 casos sugestivos de tristeza parasitária bovina (grupo B), conforme os protocolos de necropsias. Foram testadas as técnicas histoquímicas de Azul Alciano, Azul de Metileno, Azul de Toluidina, Giemsa, Gram (método de McCallum-Goodpasture), Grocott, Ácido Periódico de Schiff e Ziehl-Neelsen. Dentre estas, observou-se que as técnicas de Azul de Metileno e Azul de Toluidina permitiram observar características morfológicas e tintoriais de maneira mais nítida, auxiliando na identificação de B. bovis. Adicionalmente, foram estabelecidos vários parâmetros clínico-epidemiológicos e anatomopatológicos da babesiose por B. bovis.(AU)

Babesiosis is a hemolytic tick-borne disease caused by intraerythrocytic protozoal parasites of the genus Babesia. This is a disease of high incidence in the southern Brazil and responsible for considerable economic losses. Clinical-pathological diagnosis can be made by demonstrating the parasite by examining blood smears or fresh tissues. However, frequently, only formalin-fixed organs are sent to pathology laboratories, which makes it impossible to perform the smears. The main objective of this study was to find alternative histochemical techniques capable to improve the identification of intraerythrocytic Babesia bovis in histological sections. For this study, tissue samples from 50 bovine necropsy cases were retrospectively analyzed, which had been fixed in formalin and routinely processed for histopathology. The cases were divided into a control group, consisting of 12 cases of cerebral babesiosis with characteristic pink-cherry gray matter (group A), and 38 cases suggestive of cattle tick fever (group B), according to necropsy protocols. Histochemical techniques of Alcian Blue, Methylene Blue, Toluidine Blue, Giemsa, Gram (McCallum-Goodpasture method), Grocott, Periodic Acid of Schiff and Ziehl-Neelsen were tested. Among these, it was observed that the techniques of Methylene Blue and Toluidine Blue allowed to observe morphological and dye characteristics in a clearer way, aiding in the identification of B. bovis. In addition, several clinical-epidemiological and anatomopathological parameters of babesiosis caused by B. bovis were established.(AU)

[Babesosis--difficulty of diagnosis]. / Babesjoza--trudnosci diagnostyczne.

Human babesiosis is caused predominantly by B. microti and B. divergens, a protozooan parasites of red blood cells. Both are transmitted by Ixodes ricinus ticks, also the primary vector of Lyme disease. Clinical manifestation varied widely from asymptomatic infection to a serve rapidly fatal disease. The diagnosis of babesiosis include examination of stained blood smers, serological evaluation indirect antibody tests and PCR. With the evolution PCR--based techniques, the diagnosis and monitoring of babesial infections became more sensitive and reliable.

Babesiosis: new insights from phylogenetic analysis.

Piroplasms of the genus Babesia, along with their relatives to the Theileridae, comprise a genetically and antigenically diverse group of tick-transmitted intraerythrocytic pathogens that together have considerable veterinary, medical, and economic importance. Since the first description of a human case of babesiosis in 1957, this zoonotic infection has now attained a worldwide distribution. In the northeastern and upper midwestern United States, the transmission cycle of Babesia microti overlaps that of another well-known zoonotic agent, Borrelia burgdorferi, the causative agent of Lyme disease. Phylogenetic analysis of Babesia and Babesia-like piroplasms from human and animal sources has shown that many of the small Babesia spp., including B. microti, B. equi, B. gibsoni, and a recently described piroplasm infectious for humans known as WA1, may be phylogenetically related to Theileria. Implications of this observation may include the possible existence of an exoerythrocytic stage of parasite development and attendant features of chronicity, immune suppression, and perhaps lymphoproliferation. In this review, we provide a brief summary of recent developments in the study of Babesia and related piroplasms and speculate on the ramifications of chronic babesial infection in humans.

The occurrence of babesiasis affecting small terrestrial mammals and the importance of this zoonosis in Europe.

A short survey is given of the occurrence of babesiasis affecting small terrestrial mammals in some parts of Europe. Results obtained in studies of 7,038 small terrestrial mammals (42 species) from Czechoslovakia, Austria, Hungary, Yugoslavia and Bulgaria, show the distribution of Babesia microti in these countries. The authors found babesias in the following host species: Neomys anomalus, Clethrionomys glareolus. Microtus arvalis, M. agrestis, Apodemus agratius, A. flavicollis, A. sylvaticus and Mus musculus. The average incidence was very low-0.2% and varied in individual countries from negative to 0.7%. Problems of the natural foci of B. microti in Central Europe and discussed and hitherto recorded cases of Babesia infections in man are summarised. The epidemiological importance of the unspecific mammal hosts of B. microti is emphasised and the necessity of surveillance of this zoonosis in Europe is pointed out.