New strategies for active finding of leprosy cases in the Amazonian region

AbstractINTRODUCTION: The use of the Self-Image Form (SIF) expands the identification of active leprosy cases to neighbors of index cases.METHODS: The SIF was used to screen two groups: case (neighbors of index cases of leprosy) and control (individuals residing next to houses without leprosy) group. A specialist investigated suspected leprosy cases for disease confirmation.RESULTS: New cases of leprosy were diagnosed in the case group (n = 7, 8.6%), but not the control group.CONCLUSIONS: The new surveillance strategy is inexpensive, efficient, and feasible within a primary health strategy. Future studies can help improve the use of the SIF.

New cases of Chagas disease in a rural area of Northeast Brazilian

Abstract: INTRODUCTION: Chagas disease is considered one of the 17 most neglected tropical diseases in the World, with the most common form of vector transmission. METHODS: This structured cross-sectional study was conducted through an epidemiological survey in the Tobias Barreto municipality of Sergipe. RESULTS: Of the 255 participants, 1 (0.4%) participant was positive for human Chagas disease. Approximately 30.2% of the participants found the triatomine bugs in their houses and outbuildings. CONCLUSIONS: The detection of a case indicated transmission, which was also evidenced by the presence of triatomines and poor housing conditions.

The residual effect of deltametrine in the control of Malaria as observed on fifferent types Of walls In the Brazilian Amazon 1

The residual power of deltametrine FW (25 mg 1 .a/m2) was evaluated and compared to that of DDT (2 g i.a./m2) by means of biological tests. The different kinds of material used in constructing houses in Amazonia, such as: masonry, wood, and wattle and daub, were used. Data from logistic regression showed that the drop in mortality, the inclination of the curve in relation to time, was similar for the two insecticides in the first samples. The negative coeficient for the variable, months after application, confirmed a reduction in the activity of both insecticides. Wooden and wattle walls showed positive and negative coeficiencies respectively from the beginning. The wooden walls retained a residual effect but the wattle walls were shown to be the least indicated for the application of insecticides The experiments demonstrated a more prolonged residual effect for deltametrine as compared to DDT, and that insecticides work better on brick and cement and wooden walls than they do on wattle and daub constructions. For these reasons, it would be necessary to spray brick and cement walls every 8 months, wooden ones every 9 months and wattle constructions every 7 months to control the vectors of malaria.

Effects of planting density on flower production in carnation crop

The influence of density of planting on flower production of carnation plants grown in vinil houses, was studied. Planting densities of 233,333; 175,000 and 116,667 plants per hectare were obtained by using planting spacings of 0.20 m between rows and 0.15 m, 0,20 m and 0.30 m between plants. Data were taken on total number of flowers per plant and per hectare. As far as planting densities are concerned, there was an increase of total flower production per hectare and a decrease of slower production per plant.

Flutuação de Diptera em granja avícola, Pelotas, Rio Grande do Sul, Brasil

In order to investigate the population fluctuation of Diptera in a poultry house in Pelotas, Rio Grande do Sul, Brazil, six collection methods were utilized: 1 (0 to 7 day-old feces from chickens), 2 (7 to 14 day-old feces), 3 (14 to 21 day-old feces), 4 (0 to 21 day-old feces), 5 (accumulated feces) and 6 (tube trap). Analyses of polynomial regression were accomplished independent of the collection method. The survey was conducted from August 1998 to July 1999 in chicken houses at the Conjunto Agrotécnico Visconde da Graça. A total of 28,720 Diptera were collected, including the following species: Coproica sp. and Telomerina flavipes (Meigen, 1830) (15,640); Drosophila repleta Wollaston, 1858 (9,229); Dohrniphora cornuta (Bigot, 1857) (2,539); Ischiolepta scabricula (Haliday, 1833) (544); Lestodiplosis sp. (320); Muscina stabulans (Fallen, 1817) (159); Musca domestica L., 1758 (143); Drosophila melanogaster Meigen, 1830 (95); Telmatoscopus albipunctatus Williston, 1893 (21); Rhegmoclema sp. (14); Fannia canicularis (L., 1761) (7); Stomoxys calcitrans (L., 1758) (2); and unidentified species of Psychodidae (6) and Muscidae (1). The greatest number of species occurred in October, November and December and the fewest in August, September and April. The greatest abundance of Diptera was recorded in October (9,092), while the lowest index of capture was noted in April (658). The population fluctuation was estimated for Coproica sp. and T. flavipes, D. repleta, D. cornuta, I. scabricula and Lestodiplosis sp.

A doença de Chagas no Paraná

In recent speech in Curitiba (May 22nd, 1954), Dr. Mario Pinotti, Director, Serviço Nacional da Malaria, informed that his personnel started on February, 1953, a survey upon chagas Disease in 23 counties of the State of Paraná, South Brazil. out of 895 places surveyed, 678, or 75.7%, were infected by Triatoma infestans klug 1834 and in 234 out of those 678, or 34.5%, this vector was infected by Trypanosoma cruzi. The general natural infection of the insects examined reached 18.86%. The serological survey (Machado-Guerreiro test) was positive in 10.7% of the persons examined in jacarezinho and in 28.3% of those living in Bôa Vista. These data suggested the author to actualise the subject. During his control of severe outbreack of malaria in the North part of Paraná, from march to June 1917 he worked in 8 counties. March 1917 he photographed in Boa Vista four girls, severe cases of chronic malaria, two of which showed bi-palpebral oedema, later on considered by Dr. Pinho Simões (1943) as Romanã syndrome (created in 1935) and Prof. Salvador Mazza (1946) classified as typical cases of Chagas' Disease. now, being elapsed 36 years, the National Service of Malaria confirmed the discovery. The region surveyed was populated, in the beginning of this century, by immigrants from the State of Minas Gerais, from where the author believes that were imported the disease and its vectors. In April 1917 the A. discovered that the old town Jatahy was a big focus of Triatoma megista (now Panstrongylus megistus0. All its 43 houses were strongly infested by such hematophagus and amongst the 200 inhabitants seen many were suspicious cases of chronic cases of Chagas's Disease. In the Indians town (three tribes) of S. Pedro D' Alcantara, situated in front of Jatahy, in the left side of the river Tibagy, there were no Triatomas nor suspicious cases of trypanosomiasis. In 1919 the author started the control of the endemics by destroying the foci of Triatomas and reforming the housing. In 1946 he returned to jatahy and found the sanitary conditions of the town and its inhabitants much better. Climate of the region is favorable to spreading of all tropical diseases, being very suitable one for an extensive sanitary survey. In 1943 Dr. Pinho Simões examined 85 triatomas ( T. infestans) from six counties of the North region and found 40, or 46% infected by Trypanosoma cruzi. The highest incidences were; Joaquim Tavora 74.2% and Carlópolis 26.9%. These counties seem to be infested by Itaporanga county of São Paulo State. in 1953 Serviço nacional da Malária proved that 19 out of 23 counties surveyed were infested by Triatoma infestans. They examined 7,701 of this insect and found 1,453 positive for Trypanosoma cruzi, or 18.9%. in two counties, Jacarezinho and Sengés, were examined 2,588 human bloods, not selected, and 323, or 12.6% of such samples were positive for Chagas' Disease. This year the Malaria Service is doing insects survey in 25 other counties and DDTising infested domiciles of another eight. Such activity is very promising and should be extended to other places.

Studies in search of a suitable experimental insect model for xenodiagnosis of hosts with Chagas' disease. 1 - Comparative xenodiagnosis with nine triatomine species of animals with acute infections by Trypanosoma cruzi

In search of a suitable vector species for xenodiagnosis of humans and animals with chronic Chagas' disease we first investigated the reactions of different vector species to acute infection with Trypanosoma cruzi. Vector species utilized in this study were: Triatoma infestans, Rhodnius prolixus and Triatoma dimidiata, all well adapted to human habitats; Triatoma rubrovaria and Rhodnius neglectus both considered totally wild species; Panstrongylus megistus, Triatoma sordida, Triatoma pseudomaculata and Triatoma brasiliensis, all essentially sylvatic but some with domiciliary tendencies and others restricted to peridomestic biotopes with incipient colonization of human houses after successful eradication of T. infestans. Results summarized in Table IV suggest the following order of infectivity among the 9 studied vector species: P. megistus with 97.8% of infected bugs, T. rubrovaria with 95% of positive bugs a close second followed by T. Pseudomaculata with 94.3% and R. neglectus with 93.8% of infected bugs, almost identical thirds. R. prolixus, T. infestans and T. dimidiata exhibited low infection rates of 53.1%, 51.6% and 38.2% respectively, coupled with sharp decreases occuring with aging of infection (Fig. 1). The situation was intermediate in T. brasiliensis and T. sordida infection rates being 76.9% and 80% respectively. Results also point to the existence of a close correlation between prevalence and intensity of infection in that, species with high infection rates ranging from 93.8% to 97.8% exhibited relatively large proportions of insects (27.3% - 33.5%) harbouring very dense populations of T. cruzi. In species with low infection rates ranging from 38.2% to 53.1% the proportion of bugs demonstrating comparable parasite densities was at most 6%. No differences attributable to blood-meal size or to greater susceptibility of indigenous vector species to parasites of their own geographical area, as suggested in earlier...

Chagas' disease in the Amazon Basin: V. Periurban palms as habitats of Rhodnius robustus and Rhodnius pictipes - triatomine vectors of Chagas' disease

Trypanosoma cruzi infected Rhodnius robustus and/or Rhodnius pictipes were commonly found, in large numbers, in the Brazilian Amazonian palms Maximiliana regia ("inajá"), Acrocomia sclerocarpa ("mucajá") and Orbignya speciosa ("babaçu"). The common opossum, Didelphis marsupialis, was the animal most frequently associated with triatomine infested palms. R. pictipes, frequently light-attracted into houses from palm trees, was the probable source of an acute case of Chagas' disease in the vicinity of Belém. It is considered that triatomine infested palms are likely to cause some cases of acute Chagas' disease in the States of Amazonas and Rondônia. Possible control methods are suggested.

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.

Anopheline species, some of their habits and relation to malaria in endemic areas of Rondônia State, Amazon region of Brazil

In view of recent studies incriminating several species of anophelines, besides Anopheles darlingi, as malaria vectors in the Brazilian Amazon, we performed an anopheline survey in four localities - Ariquemes, Cujubim, Machadinho and Itapoã do Oeste - in Rondônia, the most malarious State in the Country. Twenty species were found. An. darlingi was, by far, the dominant species and the only one whose density coincided with that of malaria. On human baits it was more numerous in the immediate vincinity of houses than indoors whre, however, it was almost the only species encountered. On both situations it fed mostly at sunset and during the first half of the night. It was less numerous far from houses and scarce inside the forest. Other species (An. triannulatus, An. evansae, An. albitarsis, An. strodei) appeared in appreciable numbers only in Ariquemes, both in areas with and without malaria. The remaining species were scanty. An. darlingi was confirmed as the primary local vector.

Fonte alimentar e potencial vetorial de Triatoma vitticeps (Stal, 1859) com relação à doença de Chagas humana no estado do Espírito Santo, Brasil (Hemiptera, Reduviidae)

In paralel with several other epidemiologic and entomologic data of 19 Municipalities of Espírito Santo State, Brazil, the feeding pattern of 222 Triatoma vitticeps is studied through precipitin tests. Very high levels of natural infection with Trypanosoma cruzi are observed in adult insects, in contrast with the abscence or minimum degrees of infection among nymphs and human individuals. The precipitin tests showed the contact of the insects with multiple blood sources, chiefly human and birds, followed by rodents and marsupials. The data suggest that T. vitticeps in spite of being highly antropophilic, become infected by T. cruzi in sylvatic ambient and occasionally invade houses. The species doesn't seem to be - at least until now - a good vector in the domestic cycle of Chagas' disease. Several factors seem to be involved in this conclusion, mainly the low density of the insect in the houses, its hardness to coloniza them, its slowness concerning to suction and defecation and possibly its low susceptibility to different T. cruzi strains.

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.

Eficiência de alfacipermetrina e cipermetrina no controle de triatomíneos em Camalaú, no sul da Paraíba (Hemiptera: Reduviidae)

We sprayed, in three groups of Domiciliary Units, 10 and 15 g of alphacypermethrin and 31.3 g of cypermethrin per pump of 10 liters, equivaling, if applied on 250 [squared meters), respectiveliy, to 60 and 40 mg of a alphacypermethrin [per squared meter] and 125,2 mg of cypermethrin [per squared meter]. The invasion, colonization and cumulative indices in the houses and the positivity index in shelters near houses were very low and similar in the three groups, in the 15 months of evaluation, indicating that alphacypermethrin can replace cypermethrin. Triatoma infestans predominated in the Domiciliary Units before treatment and T. brasiliensis and T. pseudomaculata predominated after it.

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.

An outbreak of human Leishmania (Viannia) braziliensis infection

The occurence of acute cutaneous leishmaniasis among inhabitants of 10 farms within 10 Km of the hamlet of Corte de Pedra, Bahia, Brazil was studied prospectively from 1984-l989. A mean population of 1,056 inhabitants living in 146 houses were visited every 6 months and the number of sKin ulcers recorded. A leishmanin skin test survey was done people with suggestive skin scars or active disease in l984. The incidence of skin ulcers due to Leishmania (Viannia) brasiliensis (Vlb) reached 83/1,000 inhabitants but declined sharply in the subsequent 2 years. Retrospective data shows that leishamiasis is a sporadic endemic disease. Although the reasons for this epidemic are unclear some possible aetiological factors are discussed.