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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.

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.

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 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.

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.