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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.

Although bats are one of the most abundant mammals in the new world and are present in virtually all ecosystems, including urban and peri-urban environments, few studies have investigated the role of these animals in the epidemiological chain of leishmaniosis. Here, we report a study of 683 bats captured in São Paulo county (southeastern from Brazil), which were screened by serology, parasitologic methods and polymerase chain reaction (PCR) for trypanosomatids. The indirect immunofluorescent antibody test demonstrated that 0.9% of bats react positively for leishmaniosis and PCR detected the presence of DNA of Leishmania (Leishmania) amazonensis in 18 bats and Leishmania (Leishmania) infantum chagasi in 3 specimens. These results indicate that further studies are necessary to evaluate the role of bats in maintenance of the Leishmania life cycle, especially in areas where these diseases are endemic.

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 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 case of feline cutaneous leishmaniasis is reported in a domestic cat (Felis catus) as an apparently natural infection in a non-endemic area. Amastigotes were seem in smears of a nodular lesion on the cat's nose. No parasite could be seen in cytological preparations of liver or spleen but DNA obtained from a sample of the spleen produced the expected fragment in a Leishmania specific rDNA based PCR assay. The PCR product, a 520 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 from this region. This case suggests that natural transmission of this disease is occurring in this area, and that cats could act as a reservoir of L. (L.) infantum chagasi.

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.

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.