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Blood serum samples were collected from 451 bats captured within the São Paulo city from April 2007 to November 2008, and individually tested by indirect immunofluorescence assay against antigens derived from five Rickettsia species reported to occur in Brazil: the spotted fever group (SFG) species R. rickettsii, R. parkeri, R. amblyommii, R. rhipicephali, and the ancestral group species R. bellii. For this purpose, an anti-bat immunoglobulin G was produced and used in the present study. Overall, 8.6% (39/451), 9.5% (34/358), 7.8% (28/358), 1.1% (4/358), and 0% (0/358) serum samples were reactive to R. rickettsii, R. parkeri, R. amblyommii, R. rhipicephali, and R. bellii, respectively. Endpoint titers of reactive sera ranged from 64 to 256. From 20 bat species of 3 different families (Molossidae, Vespertilionidae, and Phyllostomidae), 46 animals were shown to be reactive to at least one rickettsial antigen. Seropositivity per bat species ranged from 0% to 33.3%. Most of the serologically positive sera reacted with two or more rickettsial antigens. Seropositivity for SFG rickettsial antigens in the absence of reactivity against R. bellii (ancestral group species) suggests that bats from São Paulo city can be infected by SFG rickettsiae. The possible role of soft ticks in serving as vectors of SFG rickettsiae to bats within the São Paulo city, associated to its public health risks, is discussed.

Diseases transmitted by ticks have been an important health problem all over the world. Brazilian Spotted Fever (BSF) stands for a serious epidemiological concern due to the high mortality rates pointed out. Capybaras are commonly incriminated as possible reservoirs in the BSF transmission cycle. In the last decades the numbers of these animals raised sharply and they have invaded human areas. They intensify the contact between ticks and humans beings. This study aim is to contribute to the possible role performed for this rodent in the BSF epidemiology in some areas located in Campinas region, São Paulo. Cabybaras infected by rickettsiae of BSF group were studied through the analysis of the frequencies of BSF-group rickettisae antibodies titer = 64 by indirect immunofluorescence test (IFA), and data from human cases epidemiological surveillance. The serum frequency positiveness varied greatly according to areas where animals were captured. However it was found serum positiviness only in the areas where human cases of BSF were reported. These findings suggest the capybara may be seen as sentinel animal. Due to presence of serological cross reactivity between microorganisms belonging to SF group, the results must be interpreted carefully and additional methods to distinguish pathogenic rickettsiae are required in our country. Doenças transmitidas por carrapatos vêm sendo um importante problema de saúde pública no mundo. A Febre Maculosa Brasileira (FMB) representa um sério risco epidemiológico devido às altas taxas de letalidade apresentadas. As capivaras são freqüentemente incriminadas como possíveis reservatórios no ciclo de transmissão da FMB. Nas últimas décadas o número desses animais cresceu intensamente e eles invadiram os espaços humanos. As capivaras intensificam o contato entre carrapatos e seres humanos na medida em que se apresentam muito infestadas por estes parasitos. O objetivo deste estudo é contribuir para o conhecimento do possível papel desempenhado por este roedor na epidemiologia da FMB em algumas áreas da região de Campinas, SP. Foi estudada a infecção das capivaras por rickettsias do grupo da FMB, por meio da análise das freqüências de anticorpos contra este grupo, nestes animais, e dados da vigilância epidemiológica de casos humanos. A freqüência desses anticorpos variou amplamente entre as localidades, entretanto, só foram encontrados soros com anticorpos com titulagem =64 naquelas onde havia notificação de casos humanos. Estes achados sugerem que a capivara poderá ser um animal sentinela. No entanto, devido à ocorrência de reação cruzada entre os microorganismos do grupo de FM estes resultados devem ser interpretados com cautela e são necessários métodos capazes de distinguir rickettsias patogênicas.

An autochthonous case of visceral leishmaniasis is reported in a dog (Canis familiaris) as an apparently natural infection in a non-endemic area. DNA obtained from spleen and liver samples produced the expected fragment in a Leishmania-specific rDNA-based nested-PCR assay. The PCR product, a 490 bp fragment, was sequenced and the nucleotide sequence was identical to that of Leishmania (Leishmania) infantum chagasi. These results are surprising since no autochthonous human or canine cases of visceral leishmaniasis have ever been reported in this municipality. This case suggests that natural transmission of this disease is occurring in this area.

Toxoplasmosis is a parasitic zoonosis caused by Toxoplasma gondii protozoan with a worldwide distribution. The aim of this study was to determine the frequency of IgG anti-T. gondii antibodies in bats from Sao Paulo city, Brazil. A total of 616 serum samples were collected from 22 species of bats. Anti-T. gondii antibodies were searched using the indirect fluorescent antibody test (IFAT ≥ 1:16) and IgG anti-bat antibodies produced in sheep on samples collected during 2006-2011; 32.62% (201/616) of bats had T. gondii antibodies. The modified agglutination test (MAT ≥ 1:25) was performed on samples collected during 2010-2011; 18.61% (35/188) were seropositive. The concordance between IFAT and MAT (serum samples from 2010 to 2011) by Kappa (95% CI) was 0.144, resulting in a low agreement between the techniques. The specificity and sensitivity of MAT and IFAT have not been evaluated for the diagnosis of toxoplasmosis in bats. Thus, it was verified that bats are exposed to T. gondii during their lifetime and they are also part of the toxoplasmosis epidemiology.

SUMMARYBetween December 2007 and March 2009, small mammals were captured in 6 Atlantic Forest patches in Brazil. We assessed tick-host associations and whether they differ among forest strata, sites, seasons, and host age classes or between sexes. Moreover, we assessed the exposure of animals to Rickettsia spp. In total, 432 animals were captured and 808 ticks were found on 32·9% of them. Significant differences were found among host species, collection sites, and forest strata; microhabitat preference was a strong risk factor for tick infestation. The highest tick density rates were recorded in forest fragments settled in rural areas; 91·3% of the ticks were collected from animals trapped in these forest fragments. A high prevalence (68·8%) of antibodies to Rickettsia spp. was detected among animals. This study suggests that disturbed Atlantic Forest fragments provide an environment for ticks and small mammals, which are highly exposed to rickettsiae. It also indicates that forest patches settled in rural areas are usually associated with higher small mammal diversity as well as with higher tick density rates.

This study had the purpose to compare the occurrence of Leishmania spp. in felines through two methods (cytological and serological), as well as to associate the occurrence of this protozoan with the sex, age and breed variables. Serum samples from 283 domestic felines were processed by means of Indirect Immunofluorescence Reaction (IIR), and the direct parasitological test for linfonodes was also carried out in order to verify positivity for Leishmania spp. Occurrence of 0.7% (2/283) was observed in the tested felines by means of linfonode imprinting and no animal showed title of antibodies for Leishmania spp. The two positive females were mongrel, a young female and an adult female feline. From the obtained results, no statistically significant difference was observed as regards the sex, breed and age variables in this research (p0.05). Occurrence of Leishmania spp. in the cats of this study was low. Such low incidence suggests that these hosts has no epidemiological relevance in the study area.

A serological survey was made in 973 stray dogs caught near green areas in S. Paulo county by the indirect immunofluorescence test. No positive serum was found, however autochthonous human cases of ACL that occurred in the county show the circulation of the parasite in the environment. This fact, associated with the existence of the vectors and the apparent absence of infected dogs in the areas studied, suggest that stray dog plays an insignificant role in the spread of the parasite. The cycle of the parasite in Sao Paulo county has been maintained by wild animals, hence the dog would be an accidental host just as humans.

A natural case of co-infection by Leishmania and Trypanosoma is reported in a dog (Canis familiaris) in south- western state of Mato Grosso do Sul, Brazil. Both amastigote and trypomastigote forms were observed after Giemsa staining of cytological preparations of the dog's bone marrow aspirate. No parasite was detected using medium culture inoculation of the sample. DNA obtained from the bone marrow aspirate sample and from the blood buffy coat was submitted to polymerase chain reaction (PCR) with a set of rDNA-based primers S4/S12. The nucleotide sequence of the PCR product was identical to that of Trypanosoma (Trypanozoon) evansi. The S4/S12 PCR was then used as template in a nested-PCR using a specific Leishmania set S17/S18 as primers, to explain the amastigote forms. The nucleotide sequence of the new PCR product was identical to that of Leishmania (Leishmania) chagasi. This case, as far as we know, is the first report of a dog co-infected with these parasites, suggesting that besides L. (L.) chagasi, the natural transmission of T. (T.) evansi occurs in the area under study.

A serological survey among domestic and stray dogs of the municipality of S o Jos do Rio Preto, Brazil, was conducted to identify infected animals and detect the chances of transmitting the American visceral leishmaniasis. From November 1998 to June 2000, 2,104 sera samples were tested by indirect immunofluorescence reaction, using as antigen promastigotes of Leishmania (L.) chagasi. There were 2,092 no reactive samples and 12 reactive ones. Of the dogs with reactive serum it was possible to prepare lesion smears in only 3. The slide was stained by Giemsa method and only in one of them it was found amastigotes forms characteristic of Leishmania sp. This finding suggests the need of canine serological and entomological surveillance in S o Jos do Rio Preto for an early detection of any local epidemiological changes.

Realizou-se inquérito sorológico em cães domiciliados e errantes do Município de São José do Rio Preto, SP, para identificar animais infectados e detectar a possibilidade de transmissão da leishmaniose visceral americana. De novembro de 1998 a junho de 2000, 2.104 amostras de soros foram testadas por meio da reação de imunofluorescência indireta, empregando-se como antígeno formas promastigotas de Leishmania (L.) chagasi. Observaram-se 2.092 amostras não reagentes e 12 reagentes. Dos cães com sorologia positiva foi possível realizar raspados de lesão em três animais. O material fixado em lâminas foi corado por Giemsa e, em apenas um, foram encontradas formas amastigotas características de Leishmania sp. Este resultado indica a necessidade de manutenção da vigilância sorológica canina e entomológica no município de São José do Rio Preto, a fim de detectar, precocemente, qualquer alteração na epidemiologia local. A serological survey among domestic and stray dogs of the municipality of São José do Rio Preto, Brazil, was conducted to identify infected animals and detect the chances of transmitting the American visceral leishmaniasis . From November 1998 to June 2000, 2,104 sera samples were tested by indirect immunofluorescence reaction, using as antigen promastigotes of Leishmania (L.) chagasi. There were 2,092 no reactive samples and 12 reactive ones. Of the dogs with reactive serum it was possible to prepare lesion smears in only 3. The slide was stained by Giemsa method and only in one of them it was found amastigotes forms characteristic of Leishmania sp. This finding suggests the need of canine serological and entomological surveillance in São José do Rio Preto for an early detection of any local epidemiological changes.

Durante estudos sobre a fauna flebotomínea em assentamento do Instituto Nacional de Reforma Agrária (INCRA) na Serra da Bodoquena, Estado de Mato Grosso do Sul, Brasil, foram observados cães com manifestações clínicas sugestivas de leishmaniose visceral. Inquérito sorológico para leishmaniose em 97 cães, utilizando reação de imunofluorescência indireta, mostrou 23 (23,7%) soros reagentes. Amostras do parasita foram identificadas como Leishmania (Leishmania) chagasi.

Capybaras (Hidrochoeris hidrochoeris) are 1 of the largest rodents used for meat in South and Central America. Prevalence of anti–Toxoplasma gondii antibodies in 149 feral H. hidrochoeris from the state of Sao Paulo, Brazil, was evaluated using the indirect immunofluorescent antibody test (IFAT) and the modified agglutination test (MAT). Using IFAT, antibodies (>1:16) were found in 104 (69.8%) and with the MAT, antibodies (>1:25) were found in 63 (42.3%) capybaras. This is the first report of prevalence of T. gondii antibodies in this host.