Ronalda Silva de Araújo

Genotypic Characterization of Cryptosporidium hominis from Water Samples in São Paulo, Brazil

The protozoan parasite Cryptosporidium has emerged as one of the most important water contaminants, causing waterborne outbreaks of diarrheal diseases worldwide. The small size of oocysts under the microscope and the possibility of changes in characteristics of oocysts, mainly in environmental samples, make the taxonomy of the genus difficult if morphologic characteristics are considered. This limitation encouraged the application of molecular methods to identify this microorganism. The aim of this study was to detect and identify by nested-polymerase chain reaction oocysts of Cryptosporidium present in water samples in the state of São Paulo, Brazil. Water samples were concentrated through a membrane filter, DNA was extracted by using a standard technique, and both amplification reactions used forward and reverse oligonucleotides that were complementary to Cryptosporidium 18S ribosomal RNA gene sequences. Thirty water samples from different sites of collection in the state of São Paulo were evaluated. Cryptosporidium oocysts were detected in 30% of the samples. By genoptyping, C. hominis and Cryptosporidium sp. were identified in recreational water and C. meleagridis was identified in surface water samples. This is the first report of C. hominis in environmental samples in Brazil. Although identification of Cryptosporidium is still a difficult task, molecular methods are essential for specific identification and are a helpful tool to aid to understand the epidemiology of this parasite in Brazil.

Protocol for DNA extraction of Cryptosporidium spp. oocysts in fecal samples

Molecular characterization of Cryptosporidium spp.oocysts in clinical samples is useful for public health since it allows the study of sources of contamination as well as the transmission in different geographical regions. Although widely used in developed countries, in Brazil it is restricted to academic studies, mostly using commercial kits for the extraction of genomic DNA, or in collaboration with external reference centers, rendering the method expensive and limited. The study proposes the application of the modifications recently introduced in the method improving feasibility with lower cost. This method was efficient for clinical samples preserved at -20 degrees C for up to six years and the low number of oocysts may be overcome by repetitions of extraction.

Ocorrência de Giardia, Cryptosporidium e microsporídios em animais silvestres em área de desmatamento no Estado de São Paulo, Brasil

The occurrence of Giardia, Cryptosporidium and microsporidia was investigated in 98 faecal specimens from wildlife animals, captured in an area of deforestation for the construction of two water reservoirs (Paraitinga and Biritiba), located in the municipalities of Mogi das Cruzes, Salesopolis and Biritiba-Mirim, in the state of Sao Paulo (Brazil). Samples were obtained from 46 rodents, 21 marsupials, 16 frogs, 9 bats, 3 tamarins and 3 lizards. For the detection of Giardia, Cryptosporidium and microsporidia it was used, respectively, the floatation technique with lead sulphate, the Kinyoun method and the Gram-Chromotrope staining. The total number of parasitized animals by one of these protozoans was 17.35% (17/98). Cysts of Giardia were found in faecal samples from 2 prehensile-tailed porcupines (Coendou villosus). The three positive animals for Cryptoporidium were rodents - 1 montane akodont (Akodon montensis), 1 ebony akodont (Thaptomyces nigrita) and 1 guainan squirrel (Sciurus aestuans). Microporidia spores were seen in the stools of 12 animals - 6 small rodents, including 3 montane akodonts, 1 prehensile-tailed porcupine and 2 pigmy rice rats (Oligoryzomys sp.); 3 marsupials, including 1 gray slender mouse opossum (Marmosops incanus) and 2 big eared opossums (Didelphis aurita); 3 hairy-legged vampire bats (Diphylla ecaudata). This is the first description of microsporidiosis in wildlife animals in Brazil. The present study emphasizes the importance of these animals, particularly small mammals, as potential sources of protozoan infection to other animal populations, including man, in areas of deforestation.

INTESTINAL AND PULMONARY INFECTION BY Cryptosporidium parvum IN TWO PATIENTS WITH HIV/AIDS

We describe two patients with HIV/AIDS who presented pulmonary and intestinal infection caused by Cryptosporidium parvum, with a fatal outcome. The lack of available description of changes in clinical signs and radiographic characteristics of this disease when it is located in the extra-intestinal region causes low prevalence of early diagnosis and a subsequent lack of treatment.

Ocorrência de microsporídios em pequenos mamíferos silvestres no Estado de São Paulo

ABSTRACT This study describes infection of microsporidia in the natural fauna of small wildlife animals in an area of deforestation for a water reservoir construction in the state of Sao Paulo, Brazil. It was focused on marsupials, small rodents, frogs, primates, bats, and others mammals taken from this area to access whether they may represent environmental sources of these zoonoses. From all captured animals, microsporidia spores were observed in the feces of bats, small rodents, and marsupials. This study emphasises the importance of wild animals, particularly small mammals as potential sources of microsporidia to human and animal populations from deforested areas. Keywords: microsporidia, small wildlife mammals REFERENCIAS BIBLIOGRAFICAS AVERY, S.W.; UNDEEN, A.H. The isolation of microsporidia and other pathogens from concentrated ditch water. J. Am. Mosq. Control Assoc ., v.3, p.54-58, 1987. BORNAY-LLINARES, F.J.; SILVA, A.J.; MOURA, H. et al. Immunologic, microscopic, and molecular evidence of