Made available in DSpace on 2014-06-11T19:27:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-04Bitstream added on 2014-06-13T19:56:55Z : No. of bitstreams: 1 rubini_as_me_botfmvz.pdf: 399182 bytes, checksum: cc59c7f85b768dee73fd877f9abb2a5a (MD5) / Universidade Estadual Paulista (UNESP) / Hepatozoon canis é um protozoário que infecta cães e é transmitido pela ingestão do carrapato Rhipicephalus sanguineus. Existem duas espécies distintas de Hepatozoon que infectam cães, H. canis e H. americanum. O diagnóstico de rotina é realizado pelo encontro de gamontes em esfregaço sangüíneo corados por Giemsa. O objetivo desse estudo foi verificar a prevalência de infecção em cães de áreas rurais, comparar a sensibilidade da técnica de esfregaço sangüíneo com a reação da polimerase em cadeia (PCR), e caracterizar a espécie de Hepatozoon spp. que infecta cães no Brasil. Foram realizados esfregaços sangüíneos de sangue periférico e de sangue da veia jugular. O exame por esfregaço sangüíneo detectou 17 animais positivos (11,33%), sendo 14/150 (9,3%) em esfregaços de sangue capilar (ponta de orelha), e 7/150 (4,7%) em esfregaços de sangue da veia jugular. O diagnóstico pela PCR detectou 80/150 (53,3%) amostras positivas. Carrapatos das espécies Rhipicephalus sanguineus e Amblyomma sp. foram encontrados em 36/150 (24%) dos cães, em porcentagens iguais. As espécies identificadas para o gênero Amblyomma foram: A. cajennense, A. ovale . Análises dos dados demonstraram que técnica de PCR foi mais sensível do que o exame por esfregaço sangüíneo. A espécie de Hepatozoon identicada nas amostras de cães no Brasil foi o H. canis. / Hepatozoon canis is a protozoan that infects dogs and is transmitted by the ingestion of the brown dog tick, Rhipicephalus sanguineus. Two distinct species of Hepatozoon genus can infect dogs, H. canis and H. americanum. Routine tests to detect the disease are based in direct examination of gametocytes on Giemsa stained blood smears. The purpose of this study was the investigation of disease prevalence in rural area dogs, comparison the blood smear examination to PCR in diagnostic tests, and characterize the Hepatozoon species implicated in the infection of Brazilian dogs. Blood smear examination was undertaken with blood collected by puncture of the cephalic vein and ear margin capillary bed. This technique detected 17 positive animals (11.33%), 14 out 150 (9.3%) in peripherical blood and 7 out 150 (4.7%) in cephalic vein blood. PCR tests detected 80 out 150 (53.3%) positive animals. Rhipicephalus sanguineus and Amblyomma sp. were found in 36 out 150 of the dogs (24%), in equal proportions. The identified species for Amblyomma genus were A. cajennense, A. ovale. Data analysis showed that PCR was much more sensitive compared to blood smear examination. Hepatozoon species identified in the subjects was H. canis.

Orientador: Lúcia Helena O'Dwyer de Oliveira / Banca: Marcelo Bahia / Banca: Paulo Eduardo Martins Ribolla / Resumo: Hepatozoon canis é um protozoário que infecta cães e é transmitido pela ingestão do carrapato Rhipicephalus sanguineus. Existem duas espécies distintas de Hepatozoon que infectam cães, H. canis e H. americanum. O diagnóstico de rotina é realizado pelo encontro de gamontes em esfregaço sangüíneo corados por Giemsa. O objetivo desse estudo foi verificar a prevalência de infecção em cães de áreas rurais, comparar a sensibilidade da técnica de esfregaço sangüíneo com a reação da polimerase em cadeia (PCR), e caracterizar a espécie de Hepatozoon spp. que infecta cães no Brasil. Foram realizados esfregaços sangüíneos de sangue periférico e de sangue da veia jugular. O exame por esfregaço sangüíneo detectou 17 animais positivos (11,33%), sendo 14/150 (9,3%) em esfregaços de sangue capilar (ponta de orelha), e 7/150 (4,7%) em esfregaços de sangue da veia jugular. O diagnóstico pela PCR detectou 80/150 (53,3%) amostras positivas. Carrapatos das espécies Rhipicephalus sanguineus e Amblyomma sp. foram encontrados em 36/150 (24%) dos cães, em porcentagens iguais. As espécies identificadas para o gênero Amblyomma foram: A. cajennense, A. ovale . Análises dos dados demonstraram que técnica de PCR foi mais sensível do que o exame por esfregaço sangüíneo. A espécie de Hepatozoon identicada nas amostras de cães no Brasil foi o H. canis. / Abstract: Hepatozoon canis is a protozoan that infects dogs and is transmitted by the ingestion of the brown dog tick, Rhipicephalus sanguineus. Two distinct species of Hepatozoon genus can infect dogs, H. canis and H. americanum. Routine tests to detect the disease are based in direct examination of gametocytes on Giemsa stained blood smears. The purpose of this study was the investigation of disease prevalence in rural area dogs, comparison the blood smear examination to PCR in diagnostic tests, and characterize the Hepatozoon species implicated in the infection of Brazilian dogs. Blood smear examination was undertaken with blood collected by puncture of the cephalic vein and ear margin capillary bed. This technique detected 17 positive animals (11.33%), 14 out 150 (9.3%) in peripherical blood and 7 out 150 (4.7%) in cephalic vein blood. PCR tests detected 80 out 150 (53.3%) positive animals. Rhipicephalus sanguineus and Amblyomma sp. were found in 36 out 150 of the dogs (24%), in equal proportions. The identified species for Amblyomma genus were A. cajennense, A. ovale. Data analysis showed that PCR was much more sensitive compared to blood smear examination. Hepatozoon species identified in the subjects was H. canis. / Mestre

Made available in DSpace on 2014-06-11T19:27:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-22Bitstream added on 2014-06-13T20:27:43Z : No. of bitstreams: 1 demoner_lc_me_botfmvz.pdf: 668999 bytes, checksum: f0837d7e0a185cd0a8385b4105355512 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Hepatozoon canis é um hemoparasita transmitido por carrapatos que afeta cães em diversas regiões do mundo. Rhipicephalus sanguineus é considerado seu vetor biológico, entretanto, é possível que existam outros vetores. No Brasil, H. canis é descrito principalmente em áreas rurais, onde cães podem ser infestados por outras espécies, incluindo Amblyomma spp. O objetivo do presente trabalho foi infectar experimentalmente diferentes espécies de carrapatos com H. canis, a partir de cães naturalmente infectados. Para isso, foram utilizadas ninfas de A. cajennense e R. sanguineus e adultos de A. cajennense e A. ovale. Após o ingurgitamento dos espécimes em animal infectado, foi realizada pesquisa de formas evolutivas do protozoário na hemolinfa, intestino e hemocele dos ixodídeos, por técnicas citológicas e histológicas. Alguns carrapatos foram submetidos ao diagnóstico molecular pela técnica de PCR. Somente em duas fêmeas de A. cajennense foram observadas estruturas morfologicamente semelhantes a Hepatozoon spp. e uma fêmea de A. ovale apresentou oocistos na hemocele. Além disso, duas fêmeas de A. ovale e uma de A. cajennense foram positivas na PCR. Entretanto, não é possível caracterizar essas espécies como vetores de H. canis, pois foram usados muitos exemplares nas infecções experimentais e poucos foram capazes de se infectar com o parasita. É provável que R. sanguineus tenha pouca importância epidemiológica na transmissão de H. canis no Brasil, pois este estudo, assim como pesquisas anteriores, demonstraram que a espécie foi incapaz de se infectar experimentalmente com o protozoário / Hepatozoon canis is a hemoparasite that afflicts dogs in several regions of the world. Rhipicephalus sanguineus is considered to be the biologic vector of this agent, although other species may act as possible vectors. In Brazil, H. canis is described mainly in rural areas, where dogs are infested by other species, such as Amblyomma spp. The aim of this study was to transmit experimentally H. canis to different species of ticks, using naturally infected dogs. For this purpose A. cajennense and R. sanguineus nymphs and A. cajennense and A. ovale adults were used. After the repletion of specimens fed on a naturally infected animal, we searched for development forms of the protozoa in hemolymph, gut and hemocoel of the ticks by cytological and histopathologic examinations. Some ticks were also examined by molecular detection (PCR). Only two female ticks of the species A. cajennense contained structures morphologically similar to Hepatozoon spp. and oocysts were recovered from the hemocoel of an A. ovale female. In addition, two females of A. ovale and one female of A. ovale were positive through PCR. However, our results are not enough to characterize these species as vectors of H. canis mainly because many ticks were used in experimental infections and few were infected with the parasite. It is likely that R. sanguineus has little epidemiological importance in the transmission of H. canis in Brazil, since this research and previous researchers demonstrated that R. sanguineus was unable to experimentally get infected with the protozoan

Orientador: Lucia Helena O'Dwyer / Banca: Elizabeth Moreira dos Santos Schmidt / Banca: Gervásio Henrique Bechara / Resumo: Hepatozoon canis é um hemoparasita transmitido por carrapatos que afeta cães em diversas regiões do mundo. Rhipicephalus sanguineus é considerado seu vetor biológico, entretanto, é possível que existam outros vetores. No Brasil, H. canis é descrito principalmente em áreas rurais, onde cães podem ser infestados por outras espécies, incluindo Amblyomma spp. O objetivo do presente trabalho foi infectar experimentalmente diferentes espécies de carrapatos com H. canis, a partir de cães naturalmente infectados. Para isso, foram utilizadas ninfas de A. cajennense e R. sanguineus e adultos de A. cajennense e A. ovale. Após o ingurgitamento dos espécimes em animal infectado, foi realizada pesquisa de formas evolutivas do protozoário na hemolinfa, intestino e hemocele dos ixodídeos, por técnicas citológicas e histológicas. Alguns carrapatos foram submetidos ao diagnóstico molecular pela técnica de PCR. Somente em duas fêmeas de A. cajennense foram observadas estruturas morfologicamente semelhantes a Hepatozoon spp. e uma fêmea de A. ovale apresentou oocistos na hemocele. Além disso, duas fêmeas de A. ovale e uma de A. cajennense foram positivas na PCR. Entretanto, não é possível caracterizar essas espécies como vetores de H. canis, pois foram usados muitos exemplares nas infecções experimentais e poucos foram capazes de se infectar com o parasita. É provável que R. sanguineus tenha pouca importância epidemiológica na transmissão de H. canis no Brasil, pois este estudo, assim como pesquisas anteriores, demonstraram que a espécie foi incapaz de se infectar experimentalmente com o protozoário / Abstract: Hepatozoon canis is a hemoparasite that afflicts dogs in several regions of the world. Rhipicephalus sanguineus is considered to be the biologic vector of this agent, although other species may act as possible vectors. In Brazil, H. canis is described mainly in rural areas, where dogs are infested by other species, such as Amblyomma spp. The aim of this study was to transmit experimentally H. canis to different species of ticks, using naturally infected dogs. For this purpose A. cajennense and R. sanguineus nymphs and A. cajennense and A. ovale adults were used. After the repletion of specimens fed on a naturally infected animal, we searched for development forms of the protozoa in hemolymph, gut and hemocoel of the ticks by cytological and histopathologic examinations. Some ticks were also examined by molecular detection (PCR). Only two female ticks of the species A. cajennense contained structures morphologically similar to Hepatozoon spp. and oocysts were recovered from the hemocoel of an A. ovale female. In addition, two females of A. ovale and one female of A. ovale were positive through PCR. However, our results are not enough to characterize these species as vectors of H. canis mainly because many ticks were used in experimental infections and few were infected with the parasite. It is likely that R. sanguineus has little epidemiological importance in the transmission of H. canis in Brazil, since this research and previous researchers demonstrated that R. sanguineus was unable to experimentally get infected with the protozoan / Mestre

Orientador: Lucia Helena O'Dwyer / Resumo: Animais silvestres são considerados reservatórios para uma infinidade de patógenos transmitidos por ectoparasitas, dentre os quais Hepatozoon spp. e piroplasmas; e os ectoparasitas atuam como vetores desses micro-organismos. O presente estudo teve por objetivo investigar a ocorrência de Hepatozoon spp., piroplasmas e ectoparasitas em Nasua nasua e Didelphis spp. da região peri-urbana e urbana dos municípios de Botucatu, Palmital e São Paulo, além de identificar os ectoparasitas e caracterizar morfologicamente e molecularmente os hemoparasitas encontrados. Foram coletados ectoparasitas e amostras de sangue de 69 Didelphis albiventris, 11 Didelphis aurita e 83 N. nasua. Também, foram coletadas amostras de baço e fígado de dois N. nasua e de 25 D. albiventris, para análise histológica. Os carrapatos foram identificados e dissecados para pesquisa de oocistos de Hepatozoon spp. e alguns exemplares tiveram seu DNA extraído para verificar a presença de hemoparasitas. Para identificação dos hemoparasitas foram realizados esfregaços sanguíneos, a PCR, clonagem, e posterior sequenciamento das amostras. Primeiramente, Hepatozoon procyonis foi identificado em N. nasua. Dois carrapatos Amblyomma ovale, coletados em N. nasua, também foram positivos para Hepatozoon spp. Um espécimen foi positivo para H. procyonis e o outro para Hepatozoon sp. próximo de um haplótipo de Hepatozoon americanum. Um piroplasma próximo de Babesia sp. capybara foi detectado em Amblyomma sculptum, também coletado e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Wild animals are considered reservoirs for several pathogens transmitted by ectoparasites, among which Hepatozoon spp., and piroplasms, and the ectoparasites are the vectors of these microorganisms. The present study aim to investigate the occurrence of Hepatozoon spp., piroplasms and ectoparasites in Nasua nasua and Didelphis spp., from peri-urban and urban regions of Botucatu, Palmital and São Paulo municipalities, besides to identify ectoparasites and characterize morphologically and molecularly the hemoparasites found. For this purpose, were collected ectoparasites and blood samples from 69 Didelphis albiventris, 11 Didelphis aurita e 83 N. nasua. In addition, tissue samples were collected from two N. nasua and 25 D. albiventris for histological analysis. Ticks were identified and dissected to recover oocysts of Hepatozoon spp. Some specimens of ticks had their DNA extracted for identification of hemoparasites. For parasitological diagnosis, blood smears were performed, for subsequent identification and morphometry of the parasites. The molecular diagnosis was performed by PCR or cloning and sequencing. First, we detected Hepatozoon procyonis infecting N. nasua. Amblyomma ovale collected on N. nasua was also infected by H. procyonis and by Hepatozoon sp. closely related to a Hepatozoon americanum haplotype. A piroplasm closely related to de Babesia sp. capybara was detected in Amblyomma sculptum collected also on N. nasua. We detected, for the first time, H. canis infecti... (Complete abstract click electronic access below) / Doutor

Die vorliegende epidemiologische Studie umfaßte 153 Hunde aus der Nähe von Athen, Griechenland. Um die Prävalenz arthropogener Infektionen abschätzen zu können, wurden Serumproben auf Antikörper gegen Leishmania infantum, Ehrlichia canis und Borrelia burgdorferi sowie auf Antigene von Dirofilaria immitis überprüft. Blutausstriche wurden auf das Vorkommen von Babesia canis und Hepatozoon canis untersucht. Außerdem wurden von den Hunden abgesammelte Zecken bestimmt. Bei 126 Hunden erfolgte eine klinische Allgemeinuntersuchung. Des weiteren wurden die serologischen Testverfahren ELISA und IFAT für den Nachweis von Antikörpern gegen Borrelia burgdorferi miteinander verglichen. Insgesamt waren 94 (61,4 %) der 153 untersuchten Hunde infiziert, 63 (41,2 %) Hunde wiesen Antikörper gegen Ehrlichia canis auf. Infektionen mit Borrelia burgdorferi wurden im ELISA insgesamt bei 43 (28,1 %), im IFAT bei 35 (22,9 %) Tieren nachgewiesen. Außerdem konnte bei 28 (18,3 %) Tieren eine Infektion mit Leishmania infantum und bei 20 (13,1 %) mit Dirofilaria immitis gefunden werden. Ein Nachweis von Babesia canis im Blutausstrich gelang bei vier (2,6 %) Hunden, von Hepatozoon canis nur bei einem (0,7 %) Hund. Für keinen der untersuchten Infektionserreger konnten signifikante Alters-, Geschlechts- oder Rasseprädispositionen festgestellt werden. Die Infektionsraten mit Leishmanien, Babesien, Dirofilarien und Borrelien waren bei den im Tierheim lebenden Hunden geringer als bei den Streunern. Vierundvierzig (28,8 %) der 153 getesteten Hunde waren gleichzeitig mit zwei, drei oder vier durch Arthropoden übertragene Erregerarten infiziert. Zweifachinfektionen kamen bei 29 (19,0 %), Dreifachinfektionen bei sieben (4,6 %) und Vierfachinfektionen bei acht (5,2 %) Tieren vor. In der Regel war das Risiko für Hunde, einen Erreger zu beherbergen, höher, wenn bereits eine Infektion mit einem anderen Erreger vorhanden war. Insgesamt waren 28 (18,3 %) Streuner und 15 (9,8 %) Tierheimhunde von Mehrfachinfektionen betroffen. Von den 94 mit mindestens einem der berücksichtigten Erreger infizierten Hunden wurden 75 (79,8 %) einer klinischen Untersuchung unterzogen. Dreiunddreißig (44,0 %) dieser Tiere zeigten Krankheitserscheinungen. Bei 21 (67,7 %) der 31 klinisch untersuchten und mit mehreren Erregern gleichzeitig infizierten Hunde konnten Krankheitssymptome diagnostiziert werden. Von 44 klinisch untersuchten Tieren, die nur mit einem Erreger infiziert waren, zeigten 12 (27,3 %) klinische Symptome. Die diagnostizierten Symptome waren bei allen untersuchten Erregern von einer starken Variabilität geprägt. Die Übereinstimmung der Testsysteme IFAT und ELISA für den Nachweis von Antikörpern gegen Borrelia burgdorferi lag bei 92,2 %. Die Testverfahren sind damit als nahezu gleichwertig anzusehen, wobei der ELISA etwas sensitiver zu sein scheint. Eine Infektionsgefahr besteht demnach in Griechenland vor allem für Ehrlichia canis, Borrelia burgdorferi und Leishmania infantum, aber auch für Infektionen mit Dirofilaria immitis besteht ein Risiko. Infektionen mit Babesia canis kommen in dieser Region seltener vor, es muss jedoch insbesondere bei geschwächten oder in Deutschland geborenen und somit hochempfänglichen Tieren mit Erkrankungen gerechnet werden. Hepatozoon canis ist nach den vorliegenden Ergebnissen in der Umgebung von Athen von geringer Verbreitung. Ein Rückschluß vom klinischen Bild auf das Vorliegen einer Infektion mit einem bestimmten Erreger kann aufgrund der Variabilität der Symptome in Verbindung mit häufig auftretenden Mehrfachinfektionen nicht gezogen werden. Die Möglichkeit von gleichzeitig vorliegenden Infektionen sollte in der Diagnostik und Therapie unbedingt berücksichtigt werden. Gute Haltungsbedingungen und eine tierärztliche Überwachung und Prophylaxe reduzieren offensichtlich die Inzidenz von Infektionen mit arthropodenübertragenen Erregern. Die überwiegende Anzahl (449 von 457 Exemplaren) der bestimmten Zecken gehörte der Art Rhipicephalus sanguineus an. Es wurden sechs Nymphen und 443 adulte Tiere gefunden. Die adulten Tiere verteilten sich auf 243 männliche und 200 weibliche Zecken. Bei acht Zecken handelte es sich um weibliche Ixodes ricinus. Bei aus Griechenland stammenden Hunden wie auch bei Tieren, die sich reisebegleitend dort aufgehalten haben, muss mit einer starken Infestation mit Rhipicephalus sanguineus gerechnet werden. Da Rhipicephalus sanguineus der Vektor für Ehrlichia canis, Babesia canis vogeli und Hepatozoon canis ist, sollten Prophylaxemaßnahmen eine geeignete Zeckenbekämpfung einbeziehen. / 153 dogs from the environs of Athens, Greece, were surveyed for tick infestation and arthropod borne infections. Serology was performed for Leishmania infantum, Dirofilaria immitis, Ehrlichia canis and Borrelia burgdorferi and bloodfilms were microscopically examined for Babesia canis and Hepatozoon canis. Ticks collected from the dogs were differentiated. 126 dogs underwent clinical examination. Suitability of an indirect immunofluorescent antibody assay (IFAT) and an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of antibodies to Borrelia burgdorferi was compared. Altogether 94 (61.4 %) dogs were infected with an arthropod borne pathogen, 63 (41.2 %) produced antibodies to Ehrlicha canis. ELISA detected Borrelia burgdorferi infection in 43 (28.1 %) dogs while IFAT was positive in 35 (22.9 %). 28 (18.3 %) dogs were infected with Leishmania infantum and 20 (13.1 %) with Dirofilaria immitis. Babesia canis was found in blood smears of four (2.6 %) dogs, Hepatozoon canis was detected only in one case (0,7 %). No association was found between the breed, age or sex of the dogs and any of the tested pathogens. The rate of infection with Leishmania, Babesia, Dirofilaria or Borrelia was lower in dogs living in the animal shelter than in those living as strays. 44 (28.8 %) of the 153 dogs examined were infected concurrently with two (n = 29, 19,0 %), three (n = 7, 4,6 %) or four (n = 8, 5,2 %) arthropod borne pathogens. In general the risk of infection was higher in dogs that were already infected with another pathogen. Altogether 28 (18.3 %) of the strays and 15 (9.8 %) of the dogs living in the animal shelter had a multiple infection. 75 of the 94 dogs infected with at least one of the tested pathogens were examined clinically. 33 (44.0 %) showed clinical symptoms. In 21 (67,7 %) of the 31 clinically examined dogs with multiple infection symptoms of disease were diagnosed. Twelve (27.3 %) of the 44 clinically examined dogs that were only infected with one pathogen had symptoms of some kind. Clinical symptoms varied considerably irrespective of the causative agent. The concordance of the IFAT and the ELISA for the diagnosis of Borrelia burgdorferi was 92.2 %. The serologic diagnosis of Borrelia burgdorferi with IFAT or ELISA can be regarded similarly suitable although ELISA seems to be somewhat more sensitive. In conclusion the risk of infection in Greece is particularly high for Ehrlichia canis, Borrelia burgdorferi and Leishmania infantum and Dirofilaria immitis as well. Babesia canis is obviously transmitted less. However dogs in poor condition or born in non endemic areas may acquire babesiosis in Greece. According to the results of this study Hepatozoon canis seems to be of negligible relevance in Greece. Due to the variability of the clinical symptoms and the frequent occurrence of multiple infections diagnosis based on the clinical picture only is not possible. Multiple infections should also be considered with respect to treatment. Infections with arthropod borne pathogens seem to occur less often in prophylactically treated dogs living under good conditions. Most of the examined ticks were identified as Rhipicephalus sanguineus (449 out of 457 specimens). Six nymphs and 419 adults were found. Of the adult Rhipicephalus sanguineus ticks 243 were males and 200 were females. Eight of the ticks were female Ixodes ricinus. In dogs originating from Greece as well as in dogs having accompanied tourists into Greece infestation with Rhipicephalus sanguineus is probable. As Rhipicephalus sanguineus is known to transmit Ehrlicha canis, Babesia canis vogeli and Hepatozoon canis prophylactic measures should include a suitable tick-control.

Die vorliegende epidemiologische Studie umfaßte 153 Hunde aus der Nähe von Athen, Griechenland. Um die Prävalenz arthropogener Infektionen abschätzen zu können, wurden Serumproben auf Antikörper gegen Leishmania infantum, Ehrlichia canis und Borrelia burgdorferi sowie auf Antigene von Dirofilaria immitis überprüft. Blutausstriche wurden auf das Vorkommen von Babesia canis und Hepatozoon canis untersucht. Außerdem wurden von den Hunden abgesammelte Zecken bestimmt. Bei 126 Hunden erfolgte eine klinische Allgemeinuntersuchung. Des weiteren wurden die serologischen Testverfahren ELISA und IFAT für den Nachweis von Antikörpern gegen Borrelia burgdorferi miteinander verglichen. Insgesamt waren 94 (61,4 %) der 153 untersuchten Hunde infiziert, 63 (41,2 %) Hunde wiesen Antikörper gegen Ehrlichia canis auf. Infektionen mit Borrelia burgdorferi wurden im ELISA insgesamt bei 43 (28,1 %), im IFAT bei 35 (22,9 %) Tieren nachgewiesen. Außerdem konnte bei 28 (18,3 %) Tieren eine Infektion mit Leishmania infantum und bei 20 (13,1 %) mit Dirofilaria immitis gefunden werden. Ein Nachweis von Babesia canis im Blutausstrich gelang bei vier (2,6 %) Hunden, von Hepatozoon canis nur bei einem (0,7 %) Hund. Für keinen der untersuchten Infektionserreger konnten signifikante Alters-, Geschlechts- oder Rasseprädispositionen festgestellt werden. Die Infektionsraten mit Leishmanien, Babesien, Dirofilarien und Borrelien waren bei den im Tierheim lebenden Hunden geringer als bei den Streunern. Vierundvierzig (28,8 %) der 153 getesteten Hunde waren gleichzeitig mit zwei, drei oder vier durch Arthropoden übertragene Erregerarten infiziert. Zweifachinfektionen kamen bei 29 (19,0 %), Dreifachinfektionen bei sieben (4,6 %) und Vierfachinfektionen bei acht (5,2 %) Tieren vor. In der Regel war das Risiko für Hunde, einen Erreger zu beherbergen, höher, wenn bereits eine Infektion mit einem anderen Erreger vorhanden war. Insgesamt waren 28 (18,3 %) Streuner und 15 (9,8 %) Tierheimhunde von Mehrfachinfektionen betroffen. Von den 94 mit mindestens einem der berücksichtigten Erreger infizierten Hunden wurden 75 (79,8 %) einer klinischen Untersuchung unterzogen. Dreiunddreißig (44,0 %) dieser Tiere zeigten Krankheitserscheinungen. Bei 21 (67,7 %) der 31 klinisch untersuchten und mit mehreren Erregern gleichzeitig infizierten Hunde konnten Krankheitssymptome diagnostiziert werden. Von 44 klinisch untersuchten Tieren, die nur mit einem Erreger infiziert waren, zeigten 12 (27,3 %) klinische Symptome. Die diagnostizierten Symptome waren bei allen untersuchten Erregern von einer starken Variabilität geprägt. Die Übereinstimmung der Testsysteme IFAT und ELISA für den Nachweis von Antikörpern gegen Borrelia burgdorferi lag bei 92,2 %. Die Testverfahren sind damit als nahezu gleichwertig anzusehen, wobei der ELISA etwas sensitiver zu sein scheint. Eine Infektionsgefahr besteht demnach in Griechenland vor allem für Ehrlichia canis, Borrelia burgdorferi und Leishmania infantum, aber auch für Infektionen mit Dirofilaria immitis besteht ein Risiko. Infektionen mit Babesia canis kommen in dieser Region seltener vor, es muss jedoch insbesondere bei geschwächten oder in Deutschland geborenen und somit hochempfänglichen Tieren mit Erkrankungen gerechnet werden. Hepatozoon canis ist nach den vorliegenden Ergebnissen in der Umgebung von Athen von geringer Verbreitung. Ein Rückschluß vom klinischen Bild auf das Vorliegen einer Infektion mit einem bestimmten Erreger kann aufgrund der Variabilität der Symptome in Verbindung mit häufig auftretenden Mehrfachinfektionen nicht gezogen werden. Die Möglichkeit von gleichzeitig vorliegenden Infektionen sollte in der Diagnostik und Therapie unbedingt berücksichtigt werden. Gute Haltungsbedingungen und eine tierärztliche Überwachung und Prophylaxe reduzieren offensichtlich die Inzidenz von Infektionen mit arthropodenübertragenen Erregern. Die überwiegende Anzahl (449 von 457 Exemplaren) der bestimmten Zecken gehörte der Art Rhipicephalus sanguineus an. Es wurden sechs Nymphen und 443 adulte Tiere gefunden. Die adulten Tiere verteilten sich auf 243 männliche und 200 weibliche Zecken. Bei acht Zecken handelte es sich um weibliche Ixodes ricinus. Bei aus Griechenland stammenden Hunden wie auch bei Tieren, die sich reisebegleitend dort aufgehalten haben, muss mit einer starken Infestation mit Rhipicephalus sanguineus gerechnet werden. Da Rhipicephalus sanguineus der Vektor für Ehrlichia canis, Babesia canis vogeli und Hepatozoon canis ist, sollten Prophylaxemaßnahmen eine geeignete Zeckenbekämpfung einbeziehen. / 153 dogs from the environs of Athens, Greece, were surveyed for tick infestation and arthropod borne infections. Serology was performed for Leishmania infantum, Dirofilaria immitis, Ehrlichia canis and Borrelia burgdorferi and bloodfilms were microscopically examined for Babesia canis and Hepatozoon canis. Ticks collected from the dogs were differentiated. 126 dogs underwent clinical examination. Suitability of an indirect immunofluorescent antibody assay (IFAT) and an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of antibodies to Borrelia burgdorferi was compared. Altogether 94 (61.4 %) dogs were infected with an arthropod borne pathogen, 63 (41.2 %) produced antibodies to Ehrlicha canis. ELISA detected Borrelia burgdorferi infection in 43 (28.1 %) dogs while IFAT was positive in 35 (22.9 %). 28 (18.3 %) dogs were infected with Leishmania infantum and 20 (13.1 %) with Dirofilaria immitis. Babesia canis was found in blood smears of four (2.6 %) dogs, Hepatozoon canis was detected only in one case (0,7 %). No association was found between the breed, age or sex of the dogs and any of the tested pathogens. The rate of infection with Leishmania, Babesia, Dirofilaria or Borrelia was lower in dogs living in the animal shelter than in those living as strays. 44 (28.8 %) of the 153 dogs examined were infected concurrently with two (n = 29, 19,0 %), three (n = 7, 4,6 %) or four (n = 8, 5,2 %) arthropod borne pathogens. In general the risk of infection was higher in dogs that were already infected with another pathogen. Altogether 28 (18.3 %) of the strays and 15 (9.8 %) of the dogs living in the animal shelter had a multiple infection. 75 of the 94 dogs infected with at least one of the tested pathogens were examined clinically. 33 (44.0 %) showed clinical symptoms. In 21 (67,7 %) of the 31 clinically examined dogs with multiple infection symptoms of disease were diagnosed. Twelve (27.3 %) of the 44 clinically examined dogs that were only infected with one pathogen had symptoms of some kind. Clinical symptoms varied considerably irrespective of the causative agent. The concordance of the IFAT and the ELISA for the diagnosis of Borrelia burgdorferi was 92.2 %. The serologic diagnosis of Borrelia burgdorferi with IFAT or ELISA can be regarded similarly suitable although ELISA seems to be somewhat more sensitive. In conclusion the risk of infection in Greece is particularly high for Ehrlichia canis, Borrelia burgdorferi and Leishmania infantum and Dirofilaria immitis as well. Babesia canis is obviously transmitted less. However dogs in poor condition or born in non endemic areas may acquire babesiosis in Greece. According to the results of this study Hepatozoon canis seems to be of negligible relevance in Greece. Due to the variability of the clinical symptoms and the frequent occurrence of multiple infections diagnosis based on the clinical picture only is not possible. Multiple infections should also be considered with respect to treatment. Infections with arthropod borne pathogens seem to occur less often in prophylactically treated dogs living under good conditions. Most of the examined ticks were identified as Rhipicephalus sanguineus (449 out of 457 specimens). Six nymphs and 419 adults were found. Of the adult Rhipicephalus sanguineus ticks 243 were males and 200 were females. Eight of the ticks were female Ixodes ricinus. In dogs originating from Greece as well as in dogs having accompanied tourists into Greece infestation with Rhipicephalus sanguineus is probable. As Rhipicephalus sanguineus is known to transmit Ehrlicha canis, Babesia canis vogeli and Hepatozoon canis prophylactic measures should include a suitable tick-control.