Canine Visceral Leishmaniasis in Rio de Janeiro, Brazil: clinical, parasitological, therapeutical and epidemiological findings (1977-1983)

Forty dogs from the periphery of the city of Rio de Janeiro were studied. All dogs where diagnosed as positive for leishmaniasis either parasitologically and/or serologically. Among them, 19 came from areas where only Visceral Leishmaniasis (VL) occurs (Realengo, Bangu, Senador Camará). Clinical signs of the disease were seen in 36.8% of the cases, including emaciation - 100%, lymphadenopathy and depilation - 85.7%. The other 21 dogs came from an area (Campo Grande) where both diseases (VL, and American Cutaneous Leishmaniasis - ACL) occur. Clinical signs of the disease, mainly cutaneous or mucocutaneous ulcers were seen in 76.2% of the cases. Leishmania parasites were found in 39 cases: 22% in viscera, 42.5% in viscera and normal skin and 35% in cutaneous or mucocutaneous ulcers. All the Leishmania stocks isolated from dogs which came from Realengo, Bangu, Senador Camará (VL area), and from Campo Grande (VL + ACL area) were characterized as L. donovani (except in one case) according to their schizodeme, zymodeme and serodeme. The only stock characterized as L. b. braziliensis, was isolated from the lymph node of a dog from Campo Grande with visceral disease and without skin lesions. Antimony therapy attempted in eight Leishmania donovani positive dogs was unsuccessful.

Culex siphanulatus, a new species of mosquito from the coast of Rio de Janeiro State, Brazil (Diptera: Culicidae)

Culex siphanulatus, sp. n. is described from specimens collected in bromeliads of the coast of Rio de Janeiro State, Brazil. The description includes illustrations of female, male genitalia and chaetotaxy of pupa and larva. This species is easily distinguished from the others of subgenus Microculex and does not belong to any of the four series proposed for the grouping of its species.

Epidemiological aspects of toxoplasmosis in schoolchildren residing in localities with urban or rural characteristics within the city of Rio de Janeiro, Brazil

Immunofluorescence tests (IF) for toxoplasmosis were performed on a total of 608 schoolchildren in elementary and junior high grades. 166 being in the Bonsucesso district (an urban region of Rio de Janeiro) and 442 children from locations within the lowlands of Jacarepaguá (with rural characteristics). All the IF-IgM were nonreactive, whilst 416 schoolchildren (68.4%) were IF-IgG serum-reactive ([greater than or equal to] 1:16). The percentages of serum-reactives in Jacarepaguá were significantly higher than in Bonsucesso, both as regards the total number of schoolchildren (p < 0.001), as also when subdivided according to the age-grades from six to eight years (p < 0.001) or from twelve to fourteen (p < 0.05). Both in Jacarepaguá and in Bonsucesso, the prevalence of reactions in the 12 to 14 year age-grade was significantly greater than in the 6 to 8 year age-grade (p < 0.001 in both cases). Expressively larger prevalences of serum reactions were found in Jacarepaguá among schoolchildren who preferred eating raw or undercooked meat, as well as among those having cats as pets; this occurred equally in the 6 to 8 year and in the 12 to 14 year age-grades. In Bonsucesso, the only significant difference was in the 6 to 8 year age-grades that had cats as pets. Thus, it has been verified that the risk of infection is greater and more precocious in localities with rural characteristics than in urban regions.

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.

Zoonotic cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis associated with domestic animals in Venezuela and Brazil

After outbreaks of cutaneous leishmaniasis in Solano State, Venezuela, 5% of the population had parasitized ulcers while after similar outbreaks in Mesquita, Rio de Janeiro State, Brazil, 9% had the disease. In these foci children, including some under six years of age, wre affected. There was no significant difference in the occurence of the disease according to sex or type of employment. In Solano, 3% of dogs and 28% of donkeys had parasitized lesions, while in Mesquita these indices were 19.8% and 30.8% respectively. The parasite from man, dogs and equines was identified as Leishmania (Viannia) braziliensis, by zymodeme and serodeme characterization. In these foci there is evidence suggesting that leishmaniasis is a zoonosis, possibly with equine and dogs as reservoirs, although both a wild enzootic cycle and the role of man as a source of infection can not be ruled out. Transmission is assumed to occur peridomestically by sandfly vectors such as Lutzomyia panamensis in Venezuela and Lutzomyia intermedia in Brazil. Information about the origin of these foci suggests that infected equines may be an important factor in the dissemination of the parasite in a peridomestic situation where these sandflies are abundant.

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.

Associação e distribuição das espécies de peixes na laguna de Marapendi, Rio de Janeiro, no período de março de 1985 a fevereiro de 1987

From March 1985 to February 1987 montly cast net and beach seine sambles were collected at the Marapendi lagoon, Rio de Janeiro, Brazil, to describe its ichthyofauna and analyze associations between species and their distribution in areas with different salinity regimes. A stratified random sampling design was used and the lagoon diveided in four areas (1-4) according to salinity gradient. The "Bravais-Pearson" correlation index was utilized to analyze the similarity between species and between areas and also group them according to the UPGMA method. According to the results eight species groups were established. The majority of the species were wuryhaline, having a marine origin and were distributed in areas 1, 2 and 3 (high salinity areas). The formation of smaller groups with species of fresh water origin, which occurred in areas 2, 3 and 4 is also discussed.

Bionomia de mosquitos (Diptera: Culicidae) em áreas da Mata Atlântica no município de Itaguaí, estado do Rio de janeiro, Brasil: I. Frequência intra, peri e extradomiciliar

Along 24 consecutive months, from January 1984 to December 1986, mosquito captures were performed in a rural area of said municipality. Aiming to evaluate the comparative frequency of the mosquito species inside houses and in the immediate vicinity and far from houses, the captures were made in two types of domiciles - one permanently and the other only sporadically inhabited - as well as in surrounding woods. Variations in temperature, relative humidity and rainfall were locally recorded. A tendency for domiciliation became evident by the presence of Aedes scapularis in the human domiciles, mainly in those permantely inhabited. Culex quinquefasciatus showed to be adapted to live with humans also in rural areas, in which, in some instances, insecticides had to be used to keep in under control. Such observations, mainly in terms of Ae. scapularis, reinforce the possibility of those mosquitoes, under favourable conditions, becoming carries of arboviroses to humans in rural environments.

Avaliação da infestação e diversidade de Teredinidae (Mollusca - Bivalvia) ao longo da costa do estado do Rio de Janeiro, Brasil

In order to evaluate the diversity and infestation level of Teredinidae wood-boring molluscs, ten satations were chosen along the coast of Rio de Janeiro State. Using five pine-wood panels in each station, it was possible to distinguish five areas according to species dominance. Ilha Grande Bay is characterized by the dominance of Lyrodus floridanus (Bartsch, 1922); Sepetiba Bay, by Bankia fimbriatula Moll & Roch, 1931, Tijuca Lagoon by Teredo navalis Linnaeus, 1758; Guanabara Bay by Notoredo knoxi (Bartsch, 1917) and Araruama Lagoon by Teredo furcifera Martens, 1894. Specific composition and dominance of these species were due mainly to abiotic factors such as salinity whereas infestation level was associated not only to salinity but also to other factors such as the quantity and quality of fouling, the presence of larval dispersion focus and the wood supply in each area.

Studies on sandfly fauna (Diptera: Psychodidae) in a foci of cutaneous leishmaniasis in Mesquita, Rio de Janeiro State, Brazil

Lutzomyia intermedia was the predominant species. It was collected indoors but in much higher numbers outdoors, in the close vicinity of houses. In comparative captures it was found to feed more frequently on equines, and less frequently on man and dogs. Studies, using man and animals as baits, showed that blood-feeding started in the evening, and remained stable during the night, until early morning. June, August and October were the months of highest density.

Human leptospirosis in a slum area in the city of Rio de Janeiro, Brazil: a serological and epidemiological study

A serologic survey was carried out on slum dwellers in the city of Rio de Janeiro. A total of 259 serum samples from male and female individuals of different age groups were tested for the presence of antileptospire antibodies by microagglutination. Prevalence data were analyzed in relation to the major risk factors present at the site, mainly represented by the presence of carrier animals and the occurence of frequent floods. Of the samples tested, 25% reacted with antigens of different serogroups at titres ranging from 1:100 to 1:6400, with a predominance of titres <= 1:400; 35% of positive sera reacted with leptospirae of the Icterohaemorrhagiae serogroup. Reactions with Djasiman, Panama, Javanica, Canicola, Pyrogenes, Australis, Ballum, Sejroe, Bataviae, Grippotyphosa, Autumnalis and Cynopteri were also detected, though at lower frequencies. There was no statistically significant difference between sexes, but higher prevalence rates were found to be associated with increasing age. A focus of infection was characterized, in which social and economic factors contribute to the persistance of leptospirae by favoring the proliferation of the main reservoir.