A contribution to the study of simulium and Culicoides of Rio de Janeiro: monthly incidence and biting activity

During March 1984 to February 1985, we captured simuliids and biting midges in the National Park of Tijuca, Rio de Janeiro. A study on monthly incidence and biting activity and their correlation to air temperature, relative humidity, and rainfall was made.

Substratos utilizados para a criação de dípteros caliptratos em uma área urbana do Município do Rio de Janeiro

Em uma área urbana do município do Rio de Janeiro, foram criados 10.988 dípteros caliptratos, pertencentes a quatro famílias e 22 espécies. As criações foram efetuadas em quatro etapas durante os anos de 1986 a 1987. Foram utilizados como substratos: peixe, fígado, carcaça de camundongo, fezes humanas e caninas, camarão, siri, banana, manga mamaão e tomate. As espécies criadas com maior freqüência foram: Fania sp (subgrupo pusio), Atherigona orientalis, Phaenicia eximia, Paraphrissopoda chrisostoma, Chrisomyia megacephala, Ophyra solitaria, Musca domestica, Synthesiomyia nudiseta, Phaenicia cuprina, Ophyra aenescens, Sarcophagula occidua, Morellia flavicornis, e Sarcodexia innota.

Virological study of a dengue type 1 epidemic at Rio de Janeiro

A dengue outbreak started in March, 1986 in Rio de Janeiro and spread very rapidly to other parts of the country. The great majority of cases presented classical dengue fever but there was one fatal case, confirmed by virus isolation. Dengue type 1 strains were isolated from patients and vectors (Aedes aegypti) in the area by cultivation in A. albopictus C6/36 cell line. The cytopathic effect (CPE) was studied by electron microscopy. An IgM capture test (MAC-ELISA) was applied with clear and reproducible results for diagnosis and evaluation of virus circulation; IgM antibodies appeared soon after start of clinical disease, and persisted for about 90 days in most patients. The test was type-specific in about 50% of the patients but high levels of heterologous response for type 3 were observed. An overall isolation rate of 46,8% (813 virus strains out of 1734 specimens) was recorded. The IgM test increased the number of confirmed cases to 58,2% (1479 out of 2451 suspected cases). The importance of laboratory diagnosis in all regions where the vectors are present is emphasized.

Immunological abnormalities of acquired immunodeficiency syndrome and related disorders in patients from Rio de Janeiro, Brazil

The immunoloical profile of acquired immunodeficiency syndrome (AIDS) and chronic lymphadenopathy syndrome (CLAS) in 15 and 11 Brazilian patients, respectively, was studied. The AIDS patients showed reduced percentage of total T (CD3) and T-helper-inducer (CD4) lymphocytes, relative increase in numbers of T-suppressor-cytotoxic (CD8) cells and a marked inversion of T-helper-inducer/suppressor-cytotoxic (CD4/CD8) ratio. Lymphoproliferative responses to PHA, ConA, PPD and PWM were diminished. Hypergamaglobulinemia and high levels of circulating immune complexes were also found. The CLAS patients also showed important immunological alterations, but not so intense as those with AIDS. These data seems to be similar to those observed in other parts of the world.

An outbreak of american cutaneous leishmaniasis (Leishmania braziliensis braziliensis) in a periurban area of Rio de Janeiro city, Brazil: clinical and epidemiological studies

From July 1984 to September 1986, 105 cases of American cutaneous leishmaniasis were studied in a locality closely situated to an urbanized area of the city of Rio de Janeiro, Brazil. Settement in this area was established at least 20 years ago but the first cases were noted six months prior to the beginning of this study. Cases were almost exlusively cutaneous and ulcerated, with one to six months of evolution. Montenegro's skin tests were positive in all cases and anti-Leishmania antibodies were detected by indirect immunofluorescence test in 74.3% of the patients. Parasites were demonstrated in 69.5% of cases. Domestic animals were easily found infected; 32% of the examined dogs and 30.8% of the examined equines were positive to the presence of Leishmania in cutaneous ulcerated lesions. Parasite isolates from human, dog andequines were immunologically characterized and identified as L. b. braziliensis. 73,0% of the sandfly population were Lutzomyia intermedia mainly caught on human baits and on domestic animals. Our observations suggest that this is an area of recent established L. b. braziliensis infection and that transmission probably occurs indoors or outdoors close to the houses.

Substratos utilizados para a criação de dípteros caliptratos no jardim zoológico do Rio de Janeiro (Rio-Zoo)

No Rio-Zoo, foram criados 7.377 dípteros caliptratos, pertencentes a quatro famílias e 22 espécies. As criações foram efetuadas de agosto de 1987 a abril de 1988. Foram utilizados como substratos de criação: banana, camarão, carcaça de camundongo,fezes caninas, fezes humanas, fígado bovino, lula, mamão, peixe, siri e tomate. As espécies criadas com maior freqüência foram: Fannia sp. (subgrupo pusio), Atherigona orientalis, Chrysomyia megacephala, Phaenicia eximia. Paraphrissopoda chrysosotoma, Ophyra aenescens, Synthesiomyia nudiseta, Ophyra chalcogaster, Oxisarcodexia fluminensis e Hemilucilia segmentaria. Foi efetuado um estudo, ainda que incompleto, das espécies que se desenvolvem em fezes de animais cativos do Rio-Zoo. Dentre as mais freqüentes destacam-se: Fannia sp., Sarcophagula occidua, Ophyra chalgogaster, Ravinia belforti e Phaenicia eximia.

Study of a population of Biomphalaria tenagophila (Orbigny, 1835) and of schistosomiasis transmission in "Alto da Boa Vista", Rio de Janeiro

The present study was performed using data from a Biomphalaria tenagophila population located in a water cress garden in the Alto da Boa Vista region representing an isolated focal point of schistosomiasis in the city of Rio de Janeiro. The density and age structure of this B. tenagophila population and its rate of intection by Schistosoma mansoni were studied for a period of 15 months. The snail population showed seasonal variation in density, with a decrease in number of individual at the begining of the rainy season. At the end of this season, the population consisted mainly of adults (92.8% in May 1985 and 82.8% in April 1986). The population growth curve was logistic and of sigmoidal configuration. Shiscotoma mansoni cercariae were eliminated over a short period of time (March, April and May 1986). The release of cercariae of S. mansoni and of birds seems to depend on environmental temperature, which during certain months would show a daily variation of up to 13ºC, with the lower thermal limit approaching the limit value for sporocyte development.

Enteric parasites and HIV infection: occurrence in AIDS patients in Rio de Janeiro, Brazil

The occurrence of intestinal parasites, its relation with the transmission mechanism of HIV, and the clinical state of the AIDS patients, were analyzed in 99 Group IV patients (CDC, 1986), treated at "Hospital Universitário Pedro Ernesto" (HUPE), between 1986 and 1988. The group consisted of 79 (79.8%) patients whose HIV transmission mechanism took place through sexual contact and of 16 (20.2%) who were infected through blood. Feces samples from each patient were examined by four distincts methods (Faust et al, Kato-Katz, Baermann-Moraes and Baxby et al.). The moste occuring parasites were: Cryptosporidium sp., Entamoeba coli and Endolimax nana (18.2%), Strongyloides stercoralis and Giardia lambia (15.2%). E. histolytica and/or E. hartmanni (13.1%), Ascaris lumbricoides (11.1%) and Isospora belli (10.1%). Furthermore, 74.7% of the patients carried at least one species. Intestinal parasites were found in 78.5% of the patients who acquired the HIV through sexual intercourse and in 56,3% of those infected by blood contamination. The difference, was not statistically significant (p > 0.05). In the group under study, the increase of the occurrence of parasitc infections does not seem to depend on the acquisiton of HIV through sexual contact. It appears that in developing countries, the dependancy is more related to the classic mechanisms of parasites transmission and its endemicity.

Variação sazonal da fauna vágil de Sargassum stenophyllum (Martens) em duas estações com diferentes graus de exposicäo às ondas, em Ibicuí, Baía de Sepetiba, estado do Rio de Janeiro, Brasil

The seasonal variation of the vagile fauna associated to Sargassum stenophyllum was analyzed from March/1986 to February/1987. The samples were obtained at two stations with differents intensity of wave exposures. Hight density of nematods and amphipods were observed during all of sampling period. Gammarids seems to be more dominant on the exposure site, while nematods, polychaetes and mollusks do on the sheltered one.