Infecção per os de gatos com formas vegetativas de Toxoplasma gondii Nicolle & Manceaux, 1909 sem produção de oocistos

Quatro grupos de 6 gatos (24 gatos) recém-nascidos e desmamados receberam "per os", respectivamente, suspensões de toxoplasmas de camundongos com 3-4 dias de infecção, de 4 amostras de T. gondii. Cada grupo teve um gato testemunha. Nenhum dos gatos de experiência eliminou oocistos atribuíveis a T. gondii, em períodos de observação de 6 a 20 dias; e suas fezes, conservadas 2-4 dais em bicromato de potássio a 2,5% e ministradas "per os" a camundongos, não induziram toxoplasmose nesses roedores. Com exceção dos que eram portadores de Isospora, os gatos não mostraram formas evolutivas de coccídios no epitélio intestinal. Em todos os grupos a infecção toxoplásmica foi comprovada pela positividade da reação de Sabin & Feldman (1:16 a 1:1024); e pelo isolamento de toxoplasmas pela inoculação de triturados dos seus principais órgãos em camundongos indicadores. De um modo geral, os gatos mais crescidos não mostraram sinais de doença, porém os outros, e principalmente os recém-nascidos adoeceram e vários morreram de toxoplasmose sistêmica: esplenite, hepatite, enterite, penumonia e, mais raramente, miocardite e encefalite. Os toxoplasmas foram encontrados em todos esses órgãos e, tamém, nos rins e supra-renais.

Quatro especies nuevas de nematodos del sur del Perú y redescripción de Hedruris Orestiae Moniez, 1889

En el estudio helmintológico de anfibios del género Telmatobius Wiegmann, 1834, y del pez Orestias luteus Valenciennes, 1839, de las zonas de Arequipa, Puno y del Lago Titicaca, se han encontrado nematodes de los géneros Hedruris Nitzsch, 1821 y Falcaustra Lane, 1915. Se redescribe Hedruris orestiae Moniez, 1889 y se describen cuatro especies nuevas: Hedruris moniezi sp. n., Falcaustra condorcanquii sp. n., Falcaustra pumacahuai sp. n. y Falcaustra tiahuanaquensis sp. n.

Serological survey for canine cutaneous and visceral leishmaniasis in areas at risk for transmission in Rio de Janeiro where prophylatic measures had been adopted

A serological survery for canine visceral (VL) and American cutaneous leishmaniasis (ACL) has been carried out during 1984-1989, to assess the effects of the prophylactic measures adopted in areas where there was a risk of transmission of the diseases in Rio de Janeiro. A previous serologival survey (1982/83) had detected serum positive dogas as well as the human disease in these same areas. A total fo 22,828 dogs have been examined in this last survey, 7,807 of which came from Campo Grande (VL and ACL area), 4,110 from Jacarepaguá (ACL area), 4,l46 from Realengo, 3,879 from Bangu and 2,886 from Senador Camará, (three VL areas). The analysis of these results showed a notable reduction in the number of serum positve dogs, compared to those of the first survey was 12.7%, against 0.62% of the second; (b) in Jacarepaguá (ACL) it decreased from 8.6%) to l.8% (c) in Bangu, Realengo and Senador Camará (VL) the rate decreased from 4.3% to 0.38%. The results indicate that this decrease was due to the prophylactic measures adopted in those areas.

Integrated control measures against Culex quinquefasciatus, the vector of filariasis in Recife

Integrated control measures against Culex quinquefasciastus have been implemented in a pilot urban area in Recife, Brazil. About 3,000 breeding sites found within the operational area were responsible for very high mosquito densities recorded during the pretrial period. Physical control measures have been applied to cess pits before starting a series of 37 treatments of the other sites with Bacillus sphaericus strain 2362, over 27 months. In spite of the difficulties due to environmental conditions, very significant reductions in preimaginal population of C. quinquefasciatus were achieved and, as a consequence, low adult mosquito densities were maintained for a relatively long period of time. Entomological and environmental data gathered in this pilot project can contribute to design an integrated mosquito control program in Recife city.

Monogenean parasitic on marine fishes from Perú and Chile: three new species and two new combinations

Five species of monogeneans collected from marine fishes of the Pacific coast of Chile and Perú were studied. Three of them are new species: Interniloculus chilensis n. sp. (Capsalidae), Neoheterobothrium insalaris n. sp. (Diclidophoridae) and Loxura peruensis n. sp. (Axinidae) parasitic on Sebastes capensis (Scorpaenidae), Paralichthys sp. (Bothiidae) and Belone scapularis (Belonidae), respectively. Two new combinations are proposed, Intracotyle neghmei (Microcotylidae) for Neobivagina neghmei Villalba, 1987 and Hargicotlyle conceptionensis (Diclidophoridae) for Choricotyle conceptionensis Villalba, 1987.

Control of schistosomiasis mansoni in ravena (Sabará, State of Minas Gerais, Brazil) through Water supply and quadrennial treatments

In this study, the results obtained in a control programme of schistosomiasis in Ravena (Sabará, Minas Gerais) between 1980 and 1992 are evaluated. Control measures used in this programme were: specific treatment of the people infected with Schistosoma mansoni at four year-intervals (1980/84/88) and the supply of tap water to 90% of the residences in 1980. A significant reduction of the prevalence (36.7% to 11.5%, p < 0.05) and of the intensity of the infection (228.9 eggs per gram of feces (epg), s = 3.7 to 60.3 epg, s = 3.5, p < 0.05) was observed. No cases of the severe form of the disease were diagnosed in the area. Factors independently associated with the infection were in 1980 daily sand extraction and the lack of tap water in residences and in 1992 daily sand extraction and fishing and weekly swimming. Concluding, the supply of tap water together with quadrennial treatments significantly diminished both the prevalence and intensity of the S. mansoni infection, with the additional gain of persistent low indices even after four-year intervals between the treatments.

Schistosomiasis control based on repeated chemotherapy in a rural village of the sugar-cane zone in Northeast Brazil

A schedule of repeated chemotherapy with oxamniquine, consisting of biannual treatment of school-aged (7-13 years) children and annual treatment of all other age groups, was used in a representative rural village from a highly endemic area of schistosomiasis in Pernambuco. Significant reductions in infection were obtained only after two cycles of treatment, as the overall prevalence decreased from 72.6% to 41.7% and the geometric mean egg counts per gram of faeces among positives fell from 188.4 to 76. In a school-aged cohort (n=29) three treatments at six-month intervals were necessary to significantly reduce the proportion of positives (from 75.9% to 51.7%). In a cohort of children under 7 years of age (n=20) the proportion of positives actually increased (from 30% to 45%) despite two annual treatments. Water contact was intense and host snail density was relatively high. As there is no short-term perspective of improved sanitation, auxiliary measures such as focal mollusciciding are needed for an adequate control of schistosomiasis in this and alike areas.

Epidemiological and immunological aspects of human visceral leishmaniasis on Margarita Island, Venezuela

Sixty-five patients were diagnosed with visceral leishmaniasis (VL) on Margarita Island in the decade from 1990 to1999; 86.2% were <= 3 years old. All were leishmanin-negative at diagnosis. Evaluation of 23 cured patients in 1999 revealed that 22/23 had converted to leishmanin-positive; five had persisting antibodies to rK39 antigen, with no clinical evidence of disease. Leishmanin tests were positive in 20.2% of 1,643 healthy individuals from 417 households in endemic areas. Of the positive reactors, 39.8% were identified in 35 (8.4%) of the households, 15 of which had an antecedent case of VL, a serologically positive dog or both. Weak serological activity to rK39 antigen was detected in 3 of 488 human sera from the endemic areas. The presence of micro-foci of intense peri-urban transmission and the apparent absence of other Trypanosomatidae causing human disease offer a unique opportunity for the study of reservoirs, alternative vectors and evaluation of control measures on the Island.

The patterns of tungiasis in Araruama township, state of Rio de Janeiro, Brazil

This paper describes patterns of infestation with Tunga penetrans (L., 1758) within the poor community of Araruama municipality, State of Rio de Janeiro, Brazil, assessed by the number of persons and domestic animals parasitized. The overall prevalence of infestation was 49.2% (211 parasitized hosts) of the 429 examined. Humans (p < 0.01) and dogs (p < 0.01) were the most important hosts with 62.6% and 35.6% respectively. Dogs were considered as the potential infestation source to humans. Considering sex and age groups, both measures showed a significant difference (p < 0.01): female (62.2% infested of 143 examined) and male (43.9% infested of 98 examined). All age classes were found infested with significant difference (G = 42.5; p < 0.01) and most of the infestation occurred in children in the 0-9-year old category (27.3%). In contrast and based on mean of chigoe burden per person, the parasitic intensity was significantly higher on male than on female in all age categories, except for the 50+ (H = 27.1; p < 0.01) and decreasing with the increase of age (chi2 = 69.7, A = -124.6, p < 0.01). Growing urbanization, improved housing and sewage systems, use of appropriate footwear, examination of the feet principally in young children, antitetanus prophylaxis and reduction of stray dogs population are the major prophylactic methods recommended.