Lymnaea columella: two new Brazilian localities in the states of Amazonas and Bahia

The occurrence of Lymnaea columella is recorded in Tefé, Amazonas state, where it was found together with Drepanotrema anatinum, Physa marmorata and pomacea sp. L. columella was also collected in Salvador, Bahia state, at the dique do Tororó, an urban lake formely mentioned (as "lac Baril") by Moricand (1853) as a breeding-place of Biomphalaria glabrata, Drepanotrema cimex, D. depressissimum, Pomacea lineata, P. decussata and Ancylus moricandi. The four first-mentioned species, as well as physa cubensis and Hemisinus brasiliensis, were also collected now. This is the first record of a lymnaeid in the Northeastern region of Brazil.

Infecção natural de Equus asinus por Leishmania braziliensis braziliensis - Bahia, Brasil

Em Corte de Pedra, Valença, Bahia, foi encontrado um jumento (Equus asinus), com infecção natural por Leishmania braziliensis braziliensis. O parasito foi isolado de uma lesão localizada na cicatriz da castração e identificado através de anticorpos monoclonais.

Características epidemiológicas da leishmaniose tegumentar americana em uma região endêmica do Estado da Bahia: III. Fauna flebotomínica

A fauna flebotomínica da região de Três Braços, uma área endêmica de leishmaniose cutânea-mucosa localizada no sudeste do Estado da Bahia, na região cacaueira, é muito variada. Foram identificadas 30 espécies de Lutzomyia em 13.535 exemplares coletados entre os anos de 1976 e 1984. Lu. withmani foi a espécie altamente predominante no ambiente peridoméstico e no interior das residências, com percentuais de 99,0 e 97,5, respectivamente. Na floresta, as espécies predominantes foram Lu. ayrozai e Lu. yuilli, aparecendo Lu. whitmani com apenas 1,0% do total de exemplares examinados. Lu. flaviscutellata, vetor comprovado da Leishmania mexicana amazonensis, foi também coletada em baixos índices. Lu. wellcomei, vetor da L. braziliensis braziliensis na Serra dos Carajás, Pará, Brasil, não foi encontrada na região de Três Braços onde o parasito causando infecções humanas é predominantemente L. b. braziliensis. Embora não se tenha encontrado infecção natural por promastigotas em 1.832 fêmeas de diversas espécies examinadas, discute-se a possibilidade de Lu. whitmani ser um vetor da L.b. braziliensis na região, mantendo, provavelmente, a transmissão entre o cão e o homem.

Pesquisa de anticorpos para arbovírus no soro de residentes no povoado de Corte de Pedra, Valença, Bahia

Foi realizado um estudo sorológico para verificação da presença de anticorpos para arbovírus em 288 indivíduos, residentes no povoado de Corte de Pedra, Valença, Bahia. Foram observados anticorpos inibidores de hemaglutinação e neutralizantes em 3.8% da amostra com a seguinte distribuição para flavivírus: Ilhéus (6), St. Louis (2), febre amarela (3), Rocio (1). Em um indivíduo, com residência anterior na Região Norte foram detectados anticorpos para Mayaro. Em 75 indivíduos testados aleatoriamente não foram observados anticorpos neutralizantes para o vesiculovírus Piry. Em outros 28 indivíduos, também selecionados ao acaso, anticorpos fixadores de complemento não foram detectados para os vírus dos grupos Changuinola, Phlebotomus e não grupados BE AR 408005 e BE AR 421710. Chama-se a atenção para a necessidade de estudos complementares para esclarecer a transmissão do vírus na área.

Ocorrência de planobídeos pleistocênicos no município de Jacobina, Bahia

Registramos, com base em dados paleontológicos e estratigráficos e de acordo com a morfologia da concha, Biomphalaria aff. glabrata (Say,l8l8), do Pleistoceno superior (ou Holoceno) da Gruta das Onças, distrito de Caatinga do Moura, município de Jacobina, Estado da Bahia. Registramos também mais uma evidência da antiga presença de água na referida gruta, que apoia a hipótese levantada por Cartelle & Bohorquez (1982) sobre o local.

Sarcopromusca pruna (Diptera: Muscidae) as an egg transport host of Dermatobia hominis (Diptera: Cuterebridae) in the cacau region of Bahia, Brazil

Sarcopromusca pruna appears to be the predominant transport host for Dermatobia hominis eggs among cattle herds in central eastern Bahia, Brazil. In the study area, two seasonal peaks of S. Pruna abundance coincide with those of Dermatobia, from mid July through late September and from mid November until early January, two periods of moderate monthly rainfall between anual extremes. Among more than 26,000 flies examined during the study, 75 (all female S. pruna) bore Dermatobia eggs. Certain aspects of Dermatobia behavior and ovoposition habits in the field are also discussed.

Pleistocene gastropods from Toca da Esperança, municipality of Central, State of Bahia, Brazil

Fossil shells collected during excavations in Toca da Esperança, BA, were identified on morphological grounds as: Artemon intermedius intermedius (Albers, 1857); Gastrocopta (Privatula) corticaria (Say); Bulimulus (Rhinus) heterotrichus (Moricand, 1836) and Polygyratia polygyrata polygyrata (Born, 1780). Bone samples found associated with these shells were dated by the Uranium - Thorium method as being between 204,000 and 295,000 years old (Middle - Upper Pleistocene). Species of the mastofauna also found associated, on the other hand, were identified as being of the Upper Pleistocene or even of the beginning of the Holocene. The material studied here was not dated.

The sand fly fauna (Diptera: Psychodidae: Phlebotominae) of a focus of cutaneous leishmaniasis in Ilhéus, state of Bahia, Brazil

The municipality of Ilhéus, State of Bahia, has a focus of cutaneous leishmaniasis where entomological studies were carried out to determine the sand fly species and their habits. Lutzomyia migonei, L. sallesi, L. tupynambai, L. schreiberi, L. intermedia, L. whitmani, L. yuilli yuilli, L. fischeri, L. pessoai, L. shannoni and L. misionensis were identified. Lutzomyia whitmani was the predominant species. Specimens were collected indoors, at peridomestic sites, in the cocoa plantations and in other types of collections. Females fed readily on humans and were attracted to domestic animals. Our evidence suggests that L. whitmani is a probable vector.

Ecological interactions of visceral leishmaniasis in the state of Bahia, Brazil

The laboratory and field observations summarized in this paper on visceral leishmaniasis ecology in the State of Bahia, Brazil are based on the author's observations over the past 35 years in a number of state's foci, public health records and literature citations. The disease is endemic with epidemic outbreaks occurring every ten years and its geographical distribution is expanding rapidly in the last years. Leishmania chagasi is the main ethiologic agent of the visceral leishmaniasis but Le. amazonensis s. lato was the only leishmania isolated by other authors from some visceral leishmaniasis human cases in the state. Lutzomyia longipalpis (with one or two spots on tergites III and IV and two sized different populations) was epidemiologically incriminated as the main vector. It was found naturally infected with promastigotes, and it was infected with four species of leishmanias in the laboratory. Although the experimental transmission of Le. amazonensis by the bite of Lu. longipalpis to hamsters was performed, the author was not successful in transmitting Le. chagasi in the same way. The dog is the most important domestic source for infection of the vector, however it is not a primary reservoir. The opossum Didelphis albiventris was found naturally infected with Le. chagasi but its role as reservoir is unknown. Foxes and rodents were not found infected with leishmanias in Bahia.

Comparative Analysis by Polymerase Chain Reaction Amplified Minicircles of Kinetoplast DNA of a Stable Strain of Trypanosoma cruzi from São Felipe, Bahia, its Clones and Subclones: Possibility of Predominance of a Principal Clone in this Area

Molecular characterization of one stable strain of Trypanosoma cruzi, the 21 SF, representative of the pattern of strains isolated from the endemic area of São Felipe, State of Bahia, Brazil, maintained for 15 years in laboratory by serial passages in mice and classified as biodeme Type II and zymodeme 2 has been investigated. The kinetoplast DNA (kDNA) of parental strain, 5 clones and 14 subclones were analyzed. Schizodeme was established by comparative study of the fragments obtained from digestion of the 330-bp fragments amplified by polymerase chain reaction (PCR) from the variable regions of the minicicles, and digested by restriction endonucleases Rsa I and Hinf I. Our results show a high percentual of similarity between the restriction fragment lenght polymorphism (RFLP) for the parental strain and its clones and among these individual clones and their subclones at a level of 80 to 100%.This homology indicates a predominance of the same "principal clone" in the 21SF strain and confirms the homogeneity previously observed at biological and isozymic analysis. These results suggest the possibility that the T. cruzi strains with similar biological and isoenzymic patterns, circulating in this endemic area, are representative of one dominant clone. The presence of "principal clones" could be responsible for a predominant tropism of the parasites for specific organs and tissues and this could contribute to the pattern of clinico-pathological manifestations of Chagas's disease in one geographical area.

Sylvatic vectors invading houses and the risk of emergence of cases of Chagas disease in Salvador, State of Bahia, Northeast Brazil

During the last twenty years, several adults of Triatoma tibiamaculata infected with Trypanosoma cruzi have been spontaneously caught by inhabitants, inside their houses in the new habitational district of Pituaçu of Salvador, Bahia. In this communication the authors call attention to the necessity of studies about the possibility of occurrence of new human cases of Chagas disease, to clarify the obscure origin of some positive blood donors in Salvador.

Horizontal stratification of the sand fly fauna (Diptera: Psychodidae) in a transitional vegetation between caatinga and tropical rain forest, state of Bahia, Brazil

A study about the horizontal stratification of the sand fly fauna in two distinct ecosystems, caatinga area, endemic for visceral leishmaniasis, and the tropical rain forest area, endemic for cutaneous leishmaniasis, was performed in the state of Bahia, Brazil. Lutzomyia longipalpis was predominant in the caatinga, and following it came the species L. capixaba and L. oswaldoi. In the tropical rain forest other species were found, such as L. intermedia, L. migonei, L. whitmani, L. yuilli, L.fischeri, L. damascenoi, L. evandroi, L. monticola, and L. lenti. It was found that the geographical limits of the vector species of visceral and cutaneous leishmaniasis are clearly defined by the biological and phytogeographic characteristics.

Prevalence of diarrheagenic Escherichia coli in children with diarrhea in Salvador, Bahia, Brazil

We report the frequency of the different diarrheagenic Escherichia coli (DEC) categories isolated from children with acute endemic diarrhea in Salvador, Bahia. The E. coli isolates were investigated by colony blot hibridization whit the following genes probes: eae, EAF, bfpA, Stx1, Stx2, ST-Ih, ST-Ip, LT-I, LT-II, INV, and EAEC, as virulence markers to distinguish typical and atypical EPEC, EHEC/STEC, ETEC, EIEC, and EAEC. Seven of the eight categories of DEC were detected. The most frequently isolated was atypical EPEC (10.1%) followed by ETEC (7.5%), and EAEC (4.2%). EHEC, STEC, EIEC, and typical EPEC were each detected once. The strains of ETEC, EAEC, and atypical EPEC belonged to a wide variety of serotypes. The serotypes of the others categories were O26:H11 (EHEC), O21:H21 (STEC), O142:H34 (typical EPEC), and O?H55 (EIEC). We also present the clinical manifestations and other pathogenic species observed in children with DEC. This is the first report of EHEC and STEC in Salvador, and one of the first in Brazil.