ABSTRACT
A new approach to dengue vector surveillance based on permanent egg-collection using a modified ovitrap and Bacillus thuringiensis israelensis(Bti) was evaluated in different urban landscapes in Recife, Northeast Brazil. From April 2004 to April 2005, 13 egg-collection cycles of four weeks were carried out. Geo-referenced ovitraps containing grass infusion, Bti and three paddles were placed at fixed sampling stations distributed over five selected sites. Continuous egg-collections yielded more than four million eggs laid into 464 sentinel-ovitraps over one year. The overall positive ovitrap index was 98.5 percent (over 5,616 trap observations). The egg density index ranged from 100 to 2,500 eggs per trap-cycle, indicating a wide spread and high density of Aedes aegypti (Diptera: Culicidae) breeding populations in all sites. Fluctuations in population density over time were observed, particularly a marked increase from January on, or later, according to site. Massive egg-collection carried out at one of the sites prevented such a population outbreak. At intra-site level, egg counts made it possible to identify spots where the vector population is consistently concentrated over the time, pinpointing areas that should be considered high priority for control activities. The results indicate that these could be promising strategies for detecting and preventing Ae. aegypti population outbreaks.
Subject(s)
Animals , Aedes , Insect Vectors , Mosquito Control/methods , Ovum , Dengue/prevention & control , Dengue/transmission , Population Density , Population Surveillance , SeasonsABSTRACT
A caracterização protéica dos extratos de larvas infectantes (L3) de Wuchereria bancrofti foi realizada por eletroforese em gel de poliacrilamida, em presença de dodecil sulfato de sódio (SDS-PAGE) e o reconhecimento antigênico das proteínas por Western-blot. O maior número de bandas protéicas reconhecidas foi evidenciado nos extratos AgSE (105, 100, 76, 55, 49, 39 e 32 kDa) e AgS (100, 76, 55, e 49 kDa) na presença de soros de indivíduos endêmicos normais. As bandas de 49 e 55 kDa foram reconhecidas pelos soros dos microfilarêmicos, endêmicos normais (residentes de área endêmica livres de infecção filarial) e portadores da forma crônica da doença. As larvas infectantes foram obtidas pela dissecção de mosquitos Culex quinquefasciatus infectados com sangue microfilarêmico de voluntários portadores de microfilaremia, residentes do Município de Olinda-PE. Nos 792 indivíduos investigados pela técnica da gota espessa mensurada (60æl de sangue) 87 foram positivos (11 por cento). A diferenca da positividade entre homens e mulheres não foi significativa e a faixa etária de 11 a 19 anos foi a de maior prevalência.
Subject(s)
Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Antigens, Helminth/immunology , Elephantiasis, Filarial/immunology , Helminth Proteins/analysis , Blotting, Western , Brazil , Chronic Disease , Culex/parasitology , Electrophoresis, Polyacrylamide Gel , Elephantiasis, Filarial/diagnosis , Helminth Proteins/immunology , Larva/chemistry , Larva/immunology , Wuchereria bancrofti/chemistry , Wuchereria bancrofti/immunologyABSTRACT
A filariose linfática resulta da infecçäo por três nematódeos: Brugia malayi, Brugia timori e Wuchereria bancrofti. Atingindo países considerados em desenvolvimento, é mais distribuída em áreas urbanas. Estima-se que quatro bilhöes de pessoas vivem em áreas de risco. No Brasil, a endemia é causada por W. bancrofti e foi documentada em 1878; na cidade do Recife, foi detectada em 1952. Atualmente, apenas na regiäo metropolitana do Recife e Belém, esta endemia é considerada um problema de saúde pública. Objetiva-se abordar e discutir a questäo da epidemiologia e controle da filariose linfática e revisar o histórico de seu controle desde sua notificaçäo em 1952 por Rachou, até nossos dias. Analisa-se o modelo campanhista do program institucional da Sucam/FNS e os métodos alternativos atuais propostos como inovadores. Apresenta estratégias viáveis para o controle da filariose, através da rede primária de saúde, da municipalizaçäo e do Programa de Agentes Comunitários de Saúde (Pacs).
Subject(s)
Elephantiasis, Filarial/history , Communicable Disease Control , Elephantiasis, Filarial/prevention & controlABSTRACT
A group of youngsters (4-18 years old) in northeast Brazil was studied to stablish the prevalence of anaemia and intestinal parasitism, as well as to analyse the correlation between them. Two criteria were used to determine the state of anaemia, the level of haemoglobin and the mean of corpuscular volume. The first was considered a single criterion and the second an associated criteria, used in an attempt to correlate anaemia with iron deficiency. The prevalence of intestinal parasitism was 93 per cent while the prevalence of anaemia was 43.1 per cent and 16.1 per cent according to the criteria employed (single or associated respectively). Anaemia was significantly associated with both sex and age. No significant statistical difference was observed when the association was made between each parasite and anaemia even with those more related to anaemia.
Subject(s)
Humans , Child , Adolescent , Anemia/ethnology , Helminthiasis/ethnology , Brazil/ethnology , Intestinal Diseases, Parasitic/ethnologyABSTRACT
Um projeto piloto para o controle da filariose bancroftiana foi desenvolvido em duas áreas do Recife, com índices iniciais de prevalência de microfilaremia de 10 por cento. Nas duas áreas, foi aplicado um tratamento em massa com doses baixas de dietilcarbamazina. Em uma das áreas, esse tratamento foi associado ao controle do vetor, integrando medidas físicas, como o uso de camadas flutuantes de esferas de poliestireno, ao tratamento periódico dos criadouros com a bactéria entomopatógena Bacillus sphaericus. Como resultado, a densidade populacional do vetor, de ordem de sessenta a 120 Culex/quarto/noite antes das intervençöes, foi drasticamente reduzida, mantendo-se, durante dois anos, em valores entre quatro e 16 Culex/quarto/noite. Neste contexto, as açöes para envolver a comunidade escolar local no controle do vetor resultaram na realizaçäo de atividades curriculares e extraclasses, culminando com a participaçäo efetiva de grupos de alunos ("Vigilantes de vetores") na aplicaçäo das medidas de controle e na divulgaçäo de conhecimentos básicos sobre a biologia do Culex quinquefasciatus. O entusiástico envolvimento de professores e alunos mostrou ser a escola um espaço aberto à participaçäo em programas desta natureza.
Subject(s)
Elephantiasis, Filarial , Health Education , Community Participation , Pest Control, Biological , CulexABSTRACT
The effects of radiation on the reproductive capacity and the longevity of Panstrongylus magistus were studied. An indirect correlation between longevity and radiation doses was observed. Males were more affected than females. Longevity of females submitted to 10 Gy was not different when compared to controls. Some of the irradiated males copulated and in these cases semen was transferred to females, but only few eggs were laid. Fertility was seriously affected in all irradiated groups, decreasing with increasing intensity of dose. The dose of 80 Gy induced sterility in males and females. Gelatinous spermatophores that were expelled by females irradiated with 20 and 40 Gy, may be a consequence of irradiation that induced modification in the bursa copulatrix pH
Subject(s)
Fertility , Longevity/radiation effects , Panstrongylus/radiation effectsABSTRACT
When 4th instar nymphs of Panstrongylus megistus are fed eith a saturant blood meal, there is an intense proliferation of the spermatogonia. At the end of the intermoult, the older spermatogonial cysts differentiate into 1st primary spermatocyte cysts. In the nymphs deprived of the blood meal this evolution is not observed, but a small growth of the testicular follicles occurs, due to a few mitotic divisions. This growth is observed at least, until 25 days after ecdysis. Since day 15, an autolytic process starts in the older spermatogonial cysts. The presence of exogenous juvenile hormone III (JH III) does not promote the development of the germ cells in the fasting insects. There is only a small growth of the testicular follicles and the autolytic process is also observed. In the precocious adults obtained by allatectomy or prcocene II treatment, germ cells are observed in all development stages, except packed and elongated spermatozoa bundels