Gustavo Marins de Aguiar

Ecology of the sandflies of Itaguaí, an area of cutaneous leishmaniasis in the state of Rio de Janeiro: food preferences (Diptera, Psychodidae, Phlebotominae)

Etude ecologique des simulies rencontrees dans cette region et leur role dans la transmission de la maladie. On note une predominance des femelles pour les repas sanguins

Ecologia dos flebotomíneos da Serra do Mar, Itaguaí, Estado do Rio de Janeiro, Brasil. I - A fauna flebotomínica e prevalência pelo local e tipo de captura (Diptera, Psychodidae, Phlebotominae)

Durante dois anos foi feito um estudo ecologico sobre os flebotomineos em foco de leishmaniose cutânea em Itaguai, Estado do Rio de Janeiro. As capturas (isca humana, paredes e armadilha luminosa) foram efetuadas, simultaneamente, em tres sitios de coleta: domicilio, peridomicilio e floresta. Foram capturados 10.172 flebotomineos, de 17 especies, sendo 3 do genero Brumptomyia e 14 do genero Lutzomyia. A especie mais prevalente a 100m do nivel do mar e L. intermedia, seguida de longe por L. migonei e L. fischeri. A especie mais endofila e que apresenta um certo ecletismo quanto ao local de hematofagia e L. fischeri, enquanto L. intermedia e L. migonei provaram ser mais exofilicas. L. intermedia pode ser incriminada como o principal vetor potencial do agente de leishmaniose tegumentar, pela sua prevalencia, antropofilia e por ser comprovada a veiculacao da Leishmania (Viannia) braziliensis em outras areas do Estado do Rio de Janeiro. L. fischeri, pela avidez com que pica o homem, pode ser um coadjuvante na transmissao do parasita. Sua predominância na floresta sugere participacao da transmissao em seu ciclo enzootico natural. A presenca de L. longipalpis e um risco potencial de veiculacao do agente etiologico da leishmaniose visceral nessa regiao, particularmente pela baixa imunidade da populacao local.A two-year investigation was conducted in Itaguai, State of Rio de Janeiro, an area with cases of cutaneous leishmaniasis, in order to study the ecology of sandflies and their habits and role as parasitic vector for men and animals. Capturing took place at three sites: domiciliary (human bait, walls, and light traps); peridomiciliary (walls, from baits used simultaneously: humans, dogs, and chickens; and light traps); and sylvatic (human bait and light traps). A total of 10,172 sandflies were captured, belonging to 17 species of genuses Brumptomyia França & Parrot, 1921 and Lutzomyia França, 1924. L. intermedia was predominant, 100 m above sea level, as compared to L. migonei and L. fischeri. In a drier area 300 m above sea level L. migonei was prevalent, followed by L. longipalpis and L. fischeri. The species which presented the greatest endophily was L. fischeri, showing a certain degree of eclecticism regarding the biting site. L. intermedia and L. migonei proved to be more exophilic. L. intermedia was considered to be potentially the main transmitter of the disease because of its prevalence, anthropophily, and the fact it is known to be a vector of Leishmania (V.) braziliensis in other areas of the Southeastern region of Brazil. L. fischeri, because of its anthropophily, might also be involved.

Aspectos da ecologia dos flebótomos do Parque Nacional da Serra dos Orgäos, Rio de Janeiro: II. Distribuiçäo vertical (Diptera, Psychodidae, Phlebotominae)

During one year (October, 1981 through September, 1982) captures of sandflies were simultaneously performed on human baits places on the ground and on a platform built at the canopy of a tree ten meters above the ground, in the National Park of Serra dos Orgaos, State of Rio de Janeiro, Brazil. Lutzomyia fischeri showed a decided preference to feed at the canopy, where it was the most numerous species. L. sp. 1 (a new hitherto undescribed, species) was also more frequent at the same level. L. shannoi was more ecletic, being captured mostly near the ground. All specimens of L. ayrozay (the most abundant species), L. pessoai, L. davisi, L. microps, L. monticola and L. sp. 2 (another non identified species) were only caught on baits at ground level. Few L. hirsuta (the second most numerous species) were obtained at the canopy, being the dominant sandfly near the ground during the cooler and drier months of the year. A point worth considering, besides the acrodendrophily of L. fischeri, is the preference of L. ayrozay to bite on the lower parts of the body, which leads us to suppose that its natural resting sites are fallen leaves on the ground, in the forest. Among the environmental factors which influence the stratification of the sandflies in the forest we regard luminosity to be predominent, as all specimens caught while feeding at the canopy were obtained in the darker nights (new moon and crescent) and none in the brighter nights (full moon and wane).

ASPECTS OF THE ECOLOGY OF PHLEBOTOMINES (Diptera: Psychodidae: Phlebotominae) IN AN AREA OF CUTANEOUS LEISHMANIASIS OCCURRENCE, MUNICIPALITY OF ANGRA DOS REIS, COAST OF RIO DE JANEIRO STATE, BRAZIL

Over a complete two-year period, phlebotomine specimens were caught in an area of cutaneous leishmaniasis occurrence in the municipality of Angra dos Reis. A manual suction tube was used to catch phlebotomines on house walls, and also light traps in domestic and peridomestic settings and in the forest. This yielded 14,170 specimens of 13 species: two in the genus Brumptomyia and eleven in the genus Lutzomyia. L. intermedia predominantly in domestic and peridomestic settings, with little presence in the forest, with the same trend being found in relation to L. migonei, thus proving that these species have adapted to the human environment. L. fischeri appeared to be eclectic regarding location, but was seen to be proportionally more endophilic. L. intermedia and L. migonei were more numerous in peridomestic settings, throughout the year, while L. fischeri was more numerous in domestic settings except in March, April, May and September. From the prevalence of L. intermedia, its proven anthropophily and findings of this species naturally infected with Leishmania (Viannia) braziliensis, it can be incriminated as the main vector for this agent of cutaneous leishmaniasis in the study area, especially in the peridomestic environment. L. fischeri may be a coadjuvant in carrying the parasite.

Aspectos da ecologia dos flebótomos do Parque Nacional da Serra dos Orgãos, Estado do Rio de Janeiro: V. Preferências alimentares (Diptera, Psychodidae, Phlebotominae)

In 298 hours of simultaneous sandfly captures on man, opossum and chicken in the National Park of Serra dos Orgaos, Rio de Janeiro State, 1,155 females of six species of Lutzomyia were obtained, L. ayrosai and L. hirsuta were the most numerous species, both feeding only near the ground, being decidedly anthropophilic and more active between 5 p.m. and midnight. L. fischeri was the dominant species at the canopy, where it fed chiefly on the chicken and from 4 to 5 a.m., although at ground level it fed mostly from 8 to 12 p.m. and preferred man.

Ecological Aspects of Phlebotomine Sand Flies (Diptera, Psychodidae, Phlebotominae) in Areas of American Cutaneous Leishmaniasis, in the Municipality of Paraty, Rio de Janeiro, Brazil. I-Index of Abundance by Location and Type of Capture

ABSTRACT The description of the first and autochthonous case of diffuse cutaneous leishmaniasis in the municipality of Paraty, State of Rio de Janeiro, brought the interest of this study. Sand flies were captured over a 3-yr period. Using manual suction tubes, sand flies were collected from the inner and outer walls of homes, in the living spaces of domestic animals, and in Shannon light traps, which were set up outside homes and in the forest. CDC light traps were installed inside homes, around the exterior of the houses, and along the divide and within the forest. A total of 102,937 sand flies were collected, representing 23 species—three from the genus Brumptomyia and 20 from the genus Lutzomyia. Of these, six species, Lutzomyia intermedia, Lutzomyia fischeri, Lutzomyia migonei, Lutzomyia whitmani, and Lutzomyia pessoai have already been recorded as being naturally infected by Leishmania braziliensis, and one species, Lutzomyia ayrozai, by Leishmania naiffi. Lu. intermedia is the vector of Le. braziliensis in the study area, particularly inside the homes and on the exterior of the houses. Lu. fischeri can also act as vector of Le. braziliensis in domestic environments and particularly in the wild. The third-ranked Lu. migonei was the most abundant in kennels, suggesting its canine affinity. Lu. whitmani, ranked fourth, still has characteristics indicative of the wild, but with a significant number located on the edge of the forest, suggesting a selection process of adaptation to the anthropic environment.

Description of Lutzomyia bianchigalatiae n. sp. a sand fly within the subgenus Pintomyia Costa Lima 1932 (Diptera; Psychodidae)

A new sand fly species is described based on males collected in Bananal, municipality of Mariana and the female from Sabará city, State of Minas Gerais, Brazil. Taxonomic remarks, geographic distribution and the description of new species are presented. The name Lutzomyia (Pintomyia) bianchigalatiae is in honour of Dr Eunice Aparecida Bianchi Galati, friend and researcher at the Faculdade de Saúde Pública, Universidade de São Paulo.

Aspectos da ecologia dos flebótomos do Parque Nacional da Serra dos Orgãos, Rio de Janeiro: III. Freqüência horária (Diptera, Psychodidae, Phlebotominae)

In systematic captures performed at the Serra dos Orgaos National Park, in Rio de Janeiro, Brazil, from October 1980 through September 1982, the preference of sandflies to feed at sunset or at night was confirmed. During the day sandflies were found to bite only when the weather was cloudy or during the dark moments that precede rainstorms which are frequent in summer. When three periods of captures were compared - morning (6 to 8 a.m.), sunset (5 to 7 p.m.) and night (7:30 to 9:30 p.m.) -, L. ayrozai and L. hirsuta behaved similarly, feeding mostly at sunset, while L. shannoni was more eclectic and L. fischeri preferred to bite at night. In 2-hour captures performed during 24 consecutive hours the peaks of hematophagic activity were different for L. ayrozoi and L. hirsuta: from 11 p.m. to 2 a.m. for the former and 6 to 11 p.m. for the latter. However, both can feed at any hour if conditions of temperature and humidity are favourable.

Regional Distribution and Habitats of Brazilian Phlebotomine Species

Research on phlebotomine sand-fly fauna (Diptera, Phlebotominae) has been related to the diagnosis of diseases or the identification of their vectors involved in the transmission of pathogens to humans and other animals in certain regions. It is considered that, under natural conditions, these insects are distributed in stable and balanced communities with the variables of the ecosystem as a whole. Thus, it is assumed that the emergence of many epidemic species is directly linked to problems of human ecology caused by the accidental or planned inhabitation of humans into regions where the transmitters are still unknown.