Diseminación de enteroparasitos por Calliphoridae (Insecta, Diptera)

It is establish the dissemination enteroparasite by Calliphoridae in a district situated around by Federal Capital of Argentina. The species implicated in this dispersal are: Phaenicia sericata (meigen, 1826); Calliphora vicina Robineau-Desvoidy, 1830; Chrysomya chloropyga (Wiedemann, 1818) and Phaenicia eximia (Wiedemann, 1819). Fifty two flies was studies, thirty four (65%) to belong at the family Calliphoridae. Of this thirteen (38%) have eggs of taeniid and cysts of Entamoeba coli (Grassi, 1879) and Giardia lamblia Styles, 1915.

Sarcopromusca pruna (Diptera: Muscidae) as an egg transport host of Dermatobia hominis (Diptera: Cuterebridae) in the cacau region of Bahia, Brazil

Sarcopromusca pruna appears to be the predominant transport host for Dermatobia hominis eggs among cattle herds in central eastern Bahia, Brazil. In the study area, two seasonal peaks of S. Pruna abundance coincide with those of Dermatobia, from mid July through late September and from mid November until early January, two periods of moderate monthly rainfall between anual extremes. Among more than 26,000 flies examined during the study, 75 (all female S. pruna) bore Dermatobia eggs. Certain aspects of Dermatobia behavior and ovoposition habits in the field are also discussed.

Preliminary laboratory and field trials of a heated pheromone trap for the sandfly lutzomyia logipalpis (Diptera: Psychodidae)

A heated pheromone trap for the sandfly Lutzomyia longipalpis was tested in the laboratory using filter paper or plastic vial dispensers. Male pheromone extracted from 8 male tergal glands and absorbed on to filter paper dispensers attracted 82/120 (68.3%) of virgin females released in cages. Similarly plastic vial dispensers baited with the extract of 24 males caught 73/120 (61%). In field trials carried out near januária, Minas Gerais, Brazil using the plastic dispensers baited with extracts of 50 male tergal glands only 70 female L. longipalpis were captured. Over 1000 male flies were, however, caught during 6 nights, with greater numbers in the unbaited control traps than in the pheromone baited test traps. It is concluded that at excessive concentrations male L. longipalpis pheromone may act as a repellent to conspecific males.

Susceptibility of laboratory-reared female Lutzomyia longipalpis (Lutz & Neiva, 1912) to infection by different species and strains of Leishmania Ross, 1903

A study was undertaken to compare the susceptibility of laboratory-reared female Lutzomyia longipalpis to infection by different species or strains of New World Leishmania. The sand flies proved to be highly susceptible to infection by a strain of Le. guyanensis, with flagellates developing in all (18/18) of the specimens examined. A lower infection rate of 37 per cents (10/27) was recorded in flies exposed to infection by a strain of Le. amazonensis. Flagellates developed in 13 per cents (6/46) of the sand flies that glood fed on dogs in the earlly stage of experimental infection with an old laboratory strain of Le. chagasi. In contrast, promastigotes did not develop in sand flies that blood fed on dogs with naturally acquired Le. chagasi. The naturally infected dogas were in an advanced stage of disease. Flagellates developed in 9// (3/32) of the sand flies that blood fed on lesions of hamsters infected with a strain of Le. braziliensis and in 9 per cents (3/34) of those that fed on hamsters with lesions due to a parasite fo the mexicana complex (strain MHOM/BR/73/BH121). Sand flies did not develop flagellate infections after blood feeding on hamsters bearing lesions induced by strain MHOM/BR/71/BR49. Factors influencing the susceptibility of Lu. longipalpis to infection by New World species of Leishmania are discussed.

Calyptrate diptera (Muscidae and Anthomyidae) of the state of Rio de Janeiro: I. Synanthropy

The synanthropy of Muscidae and Anthomyidae was studied in three ecologically distinct areas of the metropolitan region of Rio de Janeiro. Using baits such row fish, decomposing bovine liver, fresh human faeces and mashed banana it was found that Synthesiomyia nudiseta, Atherigona orientalis, and Musca domestica are highly synanthropic in contrast with Neomuscina pictipenis, Phaonantho devia and Morellia maculipenis found exclusively in the forest.

Determinação das exigências térmicas de Stomoxys calcitrans (L.) (Diptera, Muscidae), em condições de laboratório

The biology immature stage of Stomoxys calcitrans (L.) was studied in the laboratory under four constant temperature. The study was carried out in biological incubators at 20, 25, 30 and 35-C; 65 ñ 10% relative humidity and 14 hours of photophase. The most favorable temperature for developing eggs, larval and pupal was 25-C, while 35-C proved to be harmful for a normal developing of S. calcitrans in larval stage. The incubation periods for egg were 69.90, 42.58, 26.10, 21.78 hours and 2.91, 1.77, 1.08, 0.90 days at 20, 25, 30, 35-C, respectively . The larval stage was 18.40, 11.63, 8.55 days and, the pupal stage, 8.60, 4.54, 3.60 days at 20, 25, 30-C, respectively. Threshold temperatures for males were a little higher than for females, however, this difference was lesser than 1-C. On the other hand, the quantity of energy (GD) for developing females was a little higher than for males. No difference was observed between the two methods used for calculating the above mentioned biological parameters of S. calcitrans.

Visceral leishmaniasis in Teresina, state of Piauí, Brazil: preliminary observations on the detection and transmissibility of canine and sandfly infections

A Leishmania donovani-complex specific DNA probe was usedto confirm the widespread dissemination of amastigotes in apparently normal skinof dogs with canine visceral leishmaniasis. When Lutzomyia longipalpis were fed on abnormal skin of five naturally infected dogs 57 of 163 (35 per cent) fliesbecame infected: four of 65 flies (6 per cent) became infected when fed on apparently normal skin. The bite of a single sandfly that had fed seven days previouslyon a naturally infected dog transmitted the infection to a young dog from a non-endemic area. Within 22 days a lesion had developed at the site of the infectivebite (inner ear): 98 days after infection organisms had not disseminated throughout the skin, bone marrow, spleen or liver and the animal was still serologically negative by indirect immunofluorescence and dot-enzyme-linked immunosorbent assay. When fed Lu. longipalpis were captured from a kennel with a sick dog known to be infected, 33 out of 49 (67 per cent) of flies contained promastigotes. In contrast only two infections were detected among more than 200 sandflies captured in houses. These observations confirm the ease of transmissibility of L.chagasi from dog to sandfly to dog in Teresina. It is likely that canine VL is the major source of human VL by the transmission route dog-sandfly-human. the Lmet2 DNA probe was a useful epidemiological tool for detecting L. chagasi in sandflies.

Description of Lutzomyia (Evandromyia) sipani, a new species of Sand Fly (Diptera: Psychodidae) from Loreto Department, Peru

Lutzomyia sipani n.sp. is described from males collected in Loreto Department, Peru. The new species belongs to the subgenus Evandromyia mangabeira and confirms the presence of this group in Peru.

Ovipositional substrates used by Calyptrate Diptera in Tijuca forest, Rio de Janeiro

Twenty seven species of calyptrate muscoids were reared from a forested area of Rio de Janeiro (Tijuca Forest). Substrates for obtaining flies were beef liver, fish, mouse, frog, shrimp, snail carcasses, human faeces, banana and papaya fruits. The most frequent species found were: Fannia sp. (subgroup pusio) (49.9% on shrimp). Hemilucilia flavifacies (95.0% on liver). Phaenicia eximia (49.4% on mouse), Synthesiomyia nudiseta ( 100.0% on fish), Ophyra aenescens (100.0% on shrimp), Oxyvinia excisa (100.0% on faeces), Euboettecheria collusor (52.4% on faeces) and Pattonella intermutans (61.0% on frog).

Sand fly vectorial ecology in the state of São Paulo

Ecological aspect of sand fly distribution in the state of São Paulo, Brazil are described. The main man-biting species are Lutzomyia whitmani, Lu.pessoai, Lu.intermedia, Lu.migonei and Lu.fischeri. Their primary habitat is the forest but latter three of the above species are also encountered in domiciliary environment. Sylvatic species such as Lu.flaviscutellata bite man only rarely and Psychodopygus ayrozai seems to be more anthropophilic. The survival of sand flies in the residual forest and in cultivated areas where man has nearly destroyed the forest almost completely is analyzed. Over the last ten years the incidence of human American cutaneous leishmaniasis (ACL) has been increasing: human cases occurring within several municipalities in which there is overlapping with the distributon of domiciliary Lu.intermedia. New ACL microfoci are appearing in the state of São Paulo and these call for further study.

Biological control program against simuliids in the State of São Paulo, Brazil

In Brazil, the use of biological vector-control methods has been largely confined to experimental research, with little or no application of such techniques by public institutions responsible for implementing control programs. The notable exceptions have been the black fly control program carried out by the Health Secretariat in the State of São Paulo. Since the 1980s, São Paulo's "Superintendência de Controle de Endemias" has been conducting studies on the viability of using Bacillus thuringiensis (H-14) for simuliid control, and the results have been so encouraging that the agency has now incorporated this method into its Simuliid Control Program.

Comportamento de dípteros muscóides frente a substratos de oviposição, em laboratório, no Rio de Janeiro, RJ, Brasil

How adult females of calyptrate Diptera recognize the appropriate breeding substrate is a matter of controversy. Among holometabolic insects, the feeding opportunities of immature stages are generally determined by the adult female choice of an oviposition site. The ovipositional and larvipositional substrate preference for the synanthropic flies (Chrysomya megacephala, C. putoria, Phaenicia cuprina: Calliphoridae; Atherigona orientalis, Synthesiomyia nudiseta: Muscidae; Ravinia belforti, Parasarcophaga ruficornis, Peckia chrysostoma: Sarcophagidae) is presented in this work. The substrate used for testing were the following: bovine minced meat, fish (sardine), bovine liver, shrimp, squid, human faeces and banana. Bovine minced meat was the ovipositional and larvipositional substrate preferred by seven species. Human faeces were preferred by R. belforti.

A two years study on vectors of cutaneous leishmaniasis: Evidence for sylvatic transmission cycle in the State of Campeche, Mexico

Vectors of cutaneous leishmaniasis in the State of Campeche were studied in relation to the transmission cycle of Leishmania (Le.) mexicana. To determine how transmission of leishmaniasis occurs, we collected phlebotomine sand flies for two years. In the first year (October 1990 to November 1991) the collections were made with CDC light traps, Shannon traps and direct captures at natural shelters around the village (<200 m) of La Libertad. In the second year (February 1993 to January 1994) the catches were performed at 8 km southeast of La Libertad in the forest. Female sand flies were examined for Leishmania. During the first year, 347 sand flies of nine species were collected, most of which were Lutzomyia deleoni (61.3%). When all nine species were considered, more females than males were captured. Low densities of anthropophillic species of sand flies around the village indicated that sylvatic transmission was taking place. For the second year, 1484 sand flies of 16 species were caught. The most common were L. olmeca olmeca (21.7%), L. cruciata (19.2%) and L. ovallesi (14.1%). Similarly, more females were caught than males. Thirty-five females of five species were found infected with flagellates believed to be Leishmania sp. The highest infection rate was found in L. olmeca olmeca (7.1%) followed by L. cruciata (4.5%) and L. ovallesi (1.1%). These data plus other evidence on the epidemiology of human cases and results from reservoir studies are discussed in relation to the sylvatic transmission cycle.

Dynamics of experimental populations of native and introduced blowflies (Diptera: Calliphoridae): mathematical modelling and the transition from asymptotic equilibrium to bounded oscillations

The equilibrium dynamics of native and introduced blowflies is modelled using a density-dependent model of population growth that takes into account important features of the life-history in these flies. A theoretical analysis indicates that the product of maximum fecundity and survival is the primary determinant of the dynamics. Cochliomyia macellaria, a blowfly native to the Americas and the introduced Chrysomya megacephala and Chrysomya putoria, differ in their dynamics in that the first species shows a damping oscillatory behavior leading to a one-point equilibrium, whereas in the last two species population numbers show a two-point limit cycle. Simulations showed that variation in fecundity has a marked effect on the dynamics and indicates the possibility of transitions from one-point equilibrium to bounded oscillations and aperiodic behavior. Variation in survival has much less influence on the dynamics.

A Preliminary Analysis of Insects of Medico-legal Importance in Curitiba, State of Paraná

A survey of the carrion fauna was made at two sites in Curitiba, State of Paraná, with the objective of describing the insects associated with carrion and setting up a preliminary data-base for medico-legal purposes in south Brazil. Vertebrate exclusion experiments were carried out in each season between 1994 and 1995 with a 250 g laboratory-bred rat (Rattus norvegicus). Five stages of decomposition were identified: fresh, bloated, decaying, dry and adipocere-like. Some species showed seasonal and site preference and so could be used to identify the probable place and season where death took place. Sarconesia chlorogaster (Diptera, Calliphoridae) was restricted to an open field site and to cooler months. Hemilucilia semidiaphana (Diptera, Calliphoridae) and Pattonella resona (Diptera, Sarcophagidae) were restricted to the forest site and warmer months. Phaenicia eximia (Diptera, Calliphoridae) and Oxyletrum discicolle (Coleoptera, Silphidae) were present at both sites throughout the year and could be useful for population level analysis. Dissochaetus murray (Coleoptera, Cholevidae) was present throughout the year at the forest site and was associated with the adipocere-like stage. Ants played an important role producing post-mortem injuries to the carcasses. Insects of 32 species are reported as being useful in community level approaches