Lutzomyia Species Research Articles

Nuevos registros de flebotomíneos (Diptera: Psychodidae) en el área de influencia del río Amoyá en Chaparral, Tolima

Introduction. In Colombia, the diversity of phlebotomine sand flies is high, with 162 recorded species, and which include vectors of Leishmania spp.Objective. To identify the sand fly species of medically importance in the area of influence from Amoyá River Hydroelectric Project, Colombia.Materials and methods. Sand flies were collected with CDC light traps, Shannon traps and sticky traps, from 15 villages in Chaparral County, Tolima.Results. A total of 1,077 adult sand fly specimens were collected. Thirteen species were found in the genus Lutzomyia and one species in the genus Warileya. Among the Lutzomyia species, three species--Lutzomyia longiflocosa, Lutzomyia columbiana and Lutzomyia nuneztovari--are important for their epidemiological history. Lutzomyia suapiensis was a new record for Colombia, and Warileya rotundipennis was recorded for the first time in Tolima.Conclusions. This study contributed to an increased knowledge of Colombian sand flies in terms of (1) expanding the geographical distribution of members of the subfamily Phlebotominae, (2) gaining estimates of species-richness and species associations in central Colombia, and (3) providing a better understanding of epidemiology of leishmaniasis in the Chaparral area.

Phlebotomine sandfly fauna (Diptera: Psychodidae) of Falcon state, Venezuela

Composition, abundance and dispersion of phlebotomine sandfly fauna were studied in Falcon state, Venezuelan north-western region. The sandflies were collected by five methods in 41 localities between 0 to 1584 m. A total of 6273 specimens were collected, 17 species of Lutzomyia and 1 of Brumptomyia were identified. Of these, 10(55.56%) species are known to be anthropophilic. The predominant species was L. evansi (52.37%). The diversity and dispersion range of sandflies along an altitudinal transect, are presented. The significance of sandfly fauna in the transmission of leishmaniases in the Falcon state region is discussed.

Anthropogenic influence on the distribution, abundance and diversity of sandfly species (Diptera: Phlebotominae: Psychodidae), vectors of cutaneous leishmaniasis in Panama

In Panama, species of the genus Lutzomyia are vectors of American cutaneous leishmaniasis (ACL). There is no recent ecological information that may be used to develop tools for the control of this disease. Thus, the goal of this study was to determine the composition, distribution and diversity of Lutzomyia species that serve as vectors of ACL. Sandfly sampling was conducted in forests, fragmented forests and rural environments, in locations with records of ACL. Lutzomyia gomezi, Lutzomyia panamensis and Lutzomyia trapidoi were the most widely distributed and prevalent species. Analysis of each sampling point showed that the species abundance and diversity were greatest at points located in the fragmented forest landscape. However, when the samples were grouped according to the landscape characteristics of the locations, there was a greater diversity of species in the rural environment locations. The Kruskal Wallis analysis of species abundance found that Lu. gomezi and Lu. trapidoi were associated with fragmented environments, while Lu. panamensis, Lutzomyia olmeca bicolor and Lutzomyia ylephiletor were associated with forested environments. Therefore, we suggest that human activity influences the distribution, composition and diversity of the vector species responsible for leishmaniasis in Panama.

Breeding sites of phlebotomine sand flies (Diptera: Psychodidae) and efficiency of extraction techniques for immature stages in terra-firme forest in Amazonas State, Brazil

Information on natural breeding sites of phlebotomine sand flies is scanty, due to the difficulties of isolation of immatures from the soil where they occur. The present study investigated breeding sites in several microhabitats in a “terra-firme” forest in Pitinga, Amazonas State, Brazil. Results on the efficacy of different extraction techniques used for isolating sand flies, and the temperature and the pH of the samples collected, are presented. Samples of soil and organic matter from different microhabitats, processed by floatation-sieving, direct examination, Berlese–Tullgren, and emergence cages, revealed, for the first time in Amazonas, breeding sites in five microhabitats (tree bases, unsheltered forest floor, soil from under fallen logs, soil from under roots, and palm-tree bases). Overall, 138 immatures and 29 newly emerged adults were recovered from these microhabitats. The abundance of immatures in samples close to tree bases was significantly higher than in more open sites not adjacent to tree bases. Floatation-sieving and direct examination were the most effective techniques for immature extraction and survival, respectively. Eleven species of the genus Lutzomyia s.l. were identified, with Lutzomyia monstruosa (Floch & Abonnenc) and Lutzomyia georgii Freitas & Barrett being the most abundant. Differences in the specific composition and relative abundance of the immature and adult sand flies on tree bases suggest that breeding sites may be distant from resting or aggregation sites of adults. The pH, which revealed a slightly acidic soil, as well as the temperature, did not show any significant correlation with the number of immature sand flies collected.

Spatial and temporal patterns of occurrence of Lutzomyia sand fly species in an endemic area for cutaneous leishmaniasis in the Atlantic Forest region of northeast Brazil

Sand fly populations of different ecological niches in the Amaraji endemic American Cutaneous Leishmaniasis (ACL) focus of the Pernambuco Atlantic Forest region of northeastern Brazil were monitored spatiotemporally. Lutzomyia whitmani was dominant in all niches but occurred in smaller numbers in forested locations. L. whitmani was significantly less seasonal than the other species, being present throughout the year while other species were more abundant between February and April. These results suggest that L. whitmani may potentially be the principal vector of ACL in the region, even though the sand fly fauna was diverse: 88% were L.whitmani and 12% belonged to 11 other species. Two other species, L. complexa (1.3%) and L. migonei (0.8%), considered to be ACL vectors in other regions, were also present. This detailed picture of the sand fly population's abundance and spatiotemporal distribution provides a basis for future modeling studies of forecasting sand fly activity patterns and ACL occurrence.

Sand flies of Nicaragua: a checklist and reports of new collections

Sand flies within the genus Lutzomyia serve as the vectors for all species of the protozoan parasite Leishmania in the New World. In this paper, we present a summary of the 29 species of Lutzomyia and one of Brumptomyia previously reported for Nicaragua and report results of our recent collections of 565 sand flies at eight localities in the country from 2001-2006. Lutzomyia longipalpis was the predominant species collected within the Pacific plains region of western Nicaragua, while Lutzomyia cruciata or Lutzomyia barrettoi majuscula were the species most frequently collected in the central highlands and Atlantic plains regions. The collection of Lutzomyia durani (Vargas & Nájera) at San Jacinto in July 2001 is a new record for Nicaragua. Leishmaniasis is endemic to Nicaragua and occurs in three forms: cutaneous, mucocutaneous and visceral leishmaniasis. Cutaneous infections are the most prevalent type of leishmaniasis in Nicaragua and they occur in two different clinical manifestations, typical cutaneous leishmaniasis and atypical cutaneous leishmaniasis, depending on the species of the infecting Leishmania parasite. The distribution of sand flies collected during this study in relation to the geographic distribution of clinical forms of leishmaniasis in the country is also discussed.

Primeiro registro de Lutzomyia (Trichopygomyia) conviti Ramirez Perez, Martins & Ramirez (Diptera: Psychodidae) no Brasil

The presence of Lutzomyia conviti Ramirez Perez, Martins & Ramirez, previously found only in Venezuela and Colombia, is recorded for the first time in Brazil. Lutzomyia conviti is now added to the 229 species of Lutzomyia already registered in Brazil and to the 44 identified in São Gabriel da Cachoeira, Amazonas state. Both sexes of L. conviti were collected in 2007 and 2008 with CDC light traps in an environment of primary vegetation represented by firm land forest. The distribution range of the species is cited and discussed.

Lutzomyia Sand Fly Diversity and Rates of Infection by Wolbachia and an Exotic Leishmania Species on Barro Colorado Island, Panama

BackgroundSand flies (Diptera, Psychodidae, Phlebotominae) in the genus Lutzomyia are the predominant vectors of the protozoan disease leishmaniasis in the New World. Within the watershed of the Panama Canal, the cutaneous form of leishmaniasis is a continuous health threat for residents, tourists and members of an international research community. Here we report the results of screening a tropical forest assemblage of sand fly species for infection by both Leishmania and a microbe that can potentially serve in vector population control, the cytoplasmically transmitted rickettsia, Wolbachia pipientis. Knowing accurately which Lutzomyia species are present, what their evolutionary relationships are, and how they are infected by strains of both Leishmania and Wolbachia is of critical value for building strategies to mitigate the impact of this disease in humans.Methodology and FindingsWe collected, sorted and then used DNA sequences to determine the diversity and probable phylogenetic relationships of the Phlebotominae occurring in the understory of Barro Colorado Island in the Republic of Panama. Sequence from CO1, the DNA barcoding gene, supported 18 morphology-based species determinations while revealing the presence of two possible “cryptic” species, one (Lu. sp. nr vespertilionis) within the Vespertilionis group, the other (Lu. gomezi) within the Lutzomyia-cruciata series. Using ITS-1 and “minicircle” primers we detected Leishmania DNA in 43.3% of Lu. trapidoi, 26.3% of Lu. gomezi individuals and in 0% of the other 18 sand fly species. Identical ITS-1 sequence was obtained from the Leishmania infecting Lu. trapidoi and Lu. gomezi, sequence which was 93% similar to Leishmania (viannia) naiffi in GenBank, a species previously unknown in Panama, but recognized as a type of cutaneous leishmaniasis vectored broadly across northern and central South America. Distinct strains of the intracellular bacterium Wolbachia were detected in three of 20 sand fly species, including Lu. trapidoi, in which it frequently co-occurred with Leishmania.ConclusionsBoth morphological and molecular methods were used to examine an assemblage of 20 sand fly species occurring in the forests of the Panama Canal area. Two of these species, members of separate clades, were found to carry Leishmania at high frequency and hence are likely vectors of leishmaniasis to humans or other mammal species. A single Leishmania species, identified with high confidence as Le. naiffi, was carried by both species. That Le. naiffi is known to cause cutaneous lesions in South America but has hitherto not been reported or implicated in Panama opens the possibility that its range has recently expanded to include the Isthmus or that it occurs as a recent introduction. The occurrence of Leishmania and Wolbachia in Lu. trapidoi identifies one important vector of the disease as a potential target for gene introductions using Wolbachia population sweeps.

The Seasonal Abundance of Phlebotomine Sand Flies, Lutzomyia Species in Florida

The seasonality of phlebotomine sand flies was studied in Florida, utilizing colored light-emitting diode- and attractant-baited Mosquito Magnet MM-X traps from September 2006 to September 2008 at San Felasco Hammock Preserve State Park, Gainesville, FL. A total of 6,278 sand flies were collected from 314 actual nights and 1,692 total trap-nights, yielding 3.7 sand flies per trap-night. Lutzomyia shannoni was the predominant species, constituting 55% to 80% of the total sand fly populations collected during the studies. Both L. shannoni and L. vexator populations were highly seasonal and were moderately influenced by weather factors. Lutzomyia shannoni populations peaked in May and showed reduced activity during December, January, and February. This species was active throughout the year and showed positive and negative correlations with average monthly temperature and relative humidity, respectively. Lutzomyia vexator showed peak activity during August and October with an activity lull from December to March. This species showed a positive correlation with average monthly temperature. No correlations were observed with either species for average daily, weekly, or 1- to 8-wk-lagging precipitation, number of rainy days, wind speed, or lunar phases. Lutzomyia shannoni abundance was weakly correlated to L. vexator abundance. No other Lutzomyia spp. were collected during the study.

The Vectorial Potential ofLutzomyia (Nyssomyia) intermediaandLutzomyia (N.) whitmaniin the Transmission ofLeishmania (V.) braziliensisCan Also Be Related to Proteins Attaching

We read with great interest the report by Soares et al. [1] on the potential of Leishmania (Viannia) braziliensis to attach to the midgut of the sand flies Lutzomyia (N.) whitmani and Lutzomyia (N.) intermedia. This manuscript assesses relevant information concerning the biomolecular phenomena between Leishmania promastigotes and the midgut of Lutzomyia species that act as vectors of American Cutaneous Leishmaniasis (ACL). However, it is necessary to comment that the basis of these physiological processes is not directly driven by glycolipid lipophosphoglycan (LPG) only. Other L. (V.) braziliensis promastigotes surface components, as proteins, can also be implicated in many steps of the midgut attachment. Since 2007 we have been investigating the potential of heparin binding proteins (HPBs) from L. (V.) braziliensis promastigotes in the attachment of parasites to gut proteins from L. (N.) intermedia and L. (N.) whitmani [2]. We have indicated the existence of physicochemical conditions for the binding between the gut proteins from Lutzomyia spp. and the HPBs—a new macromolecule class involved in the recognition of the sand fly gut epithelium by L. (V.) braziliensis. We proposed that the five HPB ligands (67.0, 62.1, 59.5, 56.0, and 47.5 kDa) observed in both L. (N.) intermedia and L. (N.) whitmani are involved with the promastigote attachments to sand fly gut epithelium. Also, we suggested that the physicochemical conditions for the interaction between HBP and their ligands are more favourable in the midgut of L. (N.) whitmani than in L. (N.) intermedia. Furthermore, heparin similar molecules, synthesized by cells of midgut epithelium seem to act as anchoring sites for L. (V.) braziliensis promastigotes. The ability of promastigotes to adhere to epithelial microvillii of the Phlebotominae digestorium tube is an essential stage for the maintenance of the parasite life cycle, being a factor of distinction between infective and noninfective stains. Similarly to LPG, the HBPs are related to the infective forms of the parasite [3, 4]. In such a way, its presence can be an essential factor for the setting of promastigotes in the digestorium tube and for the continuity of the life cycle, since parasites unable to adhere to the intestinal epithelium would be rejected together with the “feces” of the insect vector [5]. In addition, L. (N.) intermedia and L. (N.) whitmani are related to L. (V.) braziliensis transmission in the same endemic area [6]. The detection of ligands with similar molecular weights in the digestorium tube of both insect species is a biochemical indicative of vectorial homogeneity of these species in the transmission of ACL. The mapping of the interactions between molecules from both parasite and vector molecules can help in the understanding of adhesion to epithelial cells through the parasite surface. Thus, our results considered together with the recent findings by Soares et al. [1] present biochemical indicatives of the epidemiological relevance of L. (N.) whitmani as a primary vector of ACL in Brazil.

Multivariate morphometric differentiation between females of two cryptic species of Lutzomyia subgenus Helcocyrtomyia (Diptera: Psychodidae)

The vectorial capacity of sibling species of the Neotropical genus Lutzomyia is likely to differ, thus a means of identifying the most important vector species is of critical importance to the epidemiology and control of the leishmanioses. Multivariate statistical procedures were employed to determine whether the females of two sibling sandfly species (genus Lutzomyia) of the subgenus Helcocyrtomyia, L. ceferinoi (N= 31) and L. erwindonaldoi (N= 32), can be discriminated on the basis of quantitative metric characters. Size independent discriminant analysis compared a set of three morphological characters of the wing (length of veins δ and α, and width of wing) measured from known specimens to detect differences between the two species. Morphometric discriminant analysis allowed differentiation of the females of both species with a high degree of accuracy (canonical correlation = 0.97; P << 0.01). The discriminant equations obtained may represent a useful and practical complementary taxonomic tool to distinguish accurately between previously unidentified female specimens of L. ceferinoi and L erwindonaldoi by measuring just three wing characters; these data can even be analyzed in the field for epidemiological in situ studies, aided by the widespread availability of laptops and statistical software.

Fauna flebotomínica (Diptera: Psychodidae) em aldeias indígenas do Estado de Mato Grosso

This study was conducted in 25 indigenous villages in 13 municipalities of the State of Mato Grosso. 4,424 specimens of 37 species of the genus Lutzomyia and one species of the genus Brumptomyia were identified. Vectors for American tegumentary leishmaniasis and visceral leishmaniasis were abundantly captured, and these represented 28.7% (Lutzomyia whitmani) and 23.6% (Lutzomyia longipalpis), respectively.

Genetic diversity of ribosomal RNA internal transcribed spacer sequences in Lutzomyia species from areas endemic for New World cutaneous leishmaniasis

In this study, each of 60 rRNA internal transcribed spacer (ITS) 1 and ITS2 sequences was determined from 44 individuals of 14 morphologically identified New World sand fly Lutzomyia species in Ecuador, and their interspecies and intraspecies genetic diversity was compared. Distinguishing between related species based on the ITS1 sequence was difficult because of variability, while the genetic diversity of ITS2 was distinct even among closely related species. Further, an assessment of intraspecies ITS sequence diversity in the subgenus Helcocyrtomyia revealed no correlation between sequence variation and geographic distribution. The results strongly suggested ITS2 to be a more suitable marker than ITS1 for the taxonomic analysis of Lutzomyia species including closely related species. Moreover, neither ITS sequence may be useful for the analysis of population structures in Lutzomyia species.

Flebótomos (Diptera: Psychodidae) del departamento de Guaviare, Colombia, con nuevos registros para el país

Although cases of leishmaniasis have been reported in the province of Guaviare, Colombia, no entomological studies were included to identify the Lutzomyia sand fly vector species in that area. Lutzomyia species were identified from four townships of Guaviare. Probable vectors were named based on those species involved in transmission in other areas. Sampling was undertaken with CDC light traps suspended at heights between 1.5 m and 9 m. Additional sand flies were collected with Shannon traps and by aspiration of adult flies from daytime resting sites. Sand flies belonging to 37 different species were collected. 35 of them were recorded for the first time in Guaviare Province. Four species were new records for Colombia: Lutzomyia begonae, L. campbelli, L. sericea and L. nematoducta. The most abundant species were L. hirsuta 24.3% (148/610), L. yuilli 15.2% (93/610), L. davisi 10.3% (63/610), followed by L. fartigi, L. carrerai, L. antunesi, L. flaviscutellata and L. olmeca bicolor. Seven of these species of have been associated previously with endemic or epidemic transmission of leishmaniasis.

Lutzomyia antunesi, Probable Vector de Leishmaniasis Cutánea en el Área Rural de Villavicencio

Identifying probable cutaneous leishmaniasis vectors in a rural area a few kilometres from the city of Villavicencio, taking the relative abundance of sand-flies and their natural infection with Leishmania spphaving into account. A CDC trap was used for sampling sand-flies in and around 15 dwellings. Pools of three females from the most abundant Lutzomyia species were used for identifying Leishmania spp. by PCR, with OL1 and OL2 primers. 1 304 sand-flies from nine species were captured, of which L. antunesi (75,6 %) and L. walkeri (19,2 %) were the most abundant. These was a low abundance of L. panamensis and L. gomezi anthropophilic species (<2,4 %). PCR detected Leishmania spp. infection in two L. antunesi groups (total=123 processed females). Due to the fact that L. antunesi was the most abundant species and was found to have Leishmania infection, it may be considered to be the main suspected cutaneous leishmaniasis vector in the rural area being studied. It is recommended that detailed studies of this species' biology (including biting and resting behaviour) should be carried out, aimed at furthering vector control measures.

Hyaluronidase of Bloodsucking Insects and Its Enhancing Effect on Leishmania Infection in Mice

BackgroundSalivary hyaluronidases have been described in a few bloodsucking arthropods. However, very little is known about the presence of this enzyme in various bloodsucking insects and no data are available on its effect on transmitted microorganisms. Here, we studied hyaluronidase activity in thirteen bloodsucking insects belonging to four different orders. In addition, we assessed the effect of hyaluronidase coinoculation on the outcome of Leishmania major infection in BALB/c mice.Principal FindingsHigh hyaluronidase activity was detected in several Diptera tested, namely deer fly Chrysops viduatus, blackflies Odagmia ornata and Eusimilium latipes, mosquito Culex quinquefasciatus, biting midge Culicoides kibunensis and sand fly Phlebotomus papatasi. Lower activity was detected in cat flea Ctenocephalides felis. No activity was found in kissing bug Rhodnius prolixus, mosquitoes Anopheles stephensi and Aedes aegypti, tse-tse fly Glossina fuscipes, stable fly Stomoxys calcitrans and human louse Pediculus humanus. Hyaluronidases of different insects vary substantially in their molecular weight, the structure of the molecule and the sensitivity to reducing conditions or sodium dodecyl sulphate. Hyaluronidase exacerbates skin lesions caused by Leishmania major; more severe lesions developed in mice where L. major promastigotes were coinjected with hyaluronidase.ConclusionsHigh hyaluronidase activities seem to be essential for insects with pool-feeding mode, where they facilitate the enlargement of the feeding lesion and serve as a spreading factor for other pharmacologically active compounds present in saliva. As this enzyme is present in all Phlebotomus and Lutzomyia species studied to date, it seems to be one of the factors responsible for enhancing activity present in sand fly saliva. We propose that salivary hyaluronidase may facilitate the spread of other vector-borne microorganisms, especially those transmitted by insects with high hyaluronidase activity, namely blackflies (Simuliidae), biting midges (Ceratopogonidae) and horse flies (Tabanidae).

Especies de Lutzomyia en un foco urbano de leishmaniasis visceral y cutánea en El Carmen de Bolívar, Bolívar, Colombia

A focus of leishmanias transmission was reported in the municipality of El Carmen de Bolívar in the province of Bolívar, Colombia, where both cutaneous and visceral leishmaniasis cases have occured. Vector identification, ecology and behavior of potential vector species have not been characterized in this region, however. Sand fly species of the genus Lutzomyia were identified, patterns of behavior were established, and their possible roles in leishmaniasis transmission were evaluated. CDC light traps were used in several different habitats; in addition, monthly collections were made with human bait as attraction inside houses as well as outdoor Shannon trap collections. The collection data were compared with independent variables including precipitation, temperature, relative humidity and wind velocity by means of a Pearson correlation matrix to estimate levels of association and to determine the influence of the climatic conditions on the density of adults of Lutzomyia evansi and L. gomezi in each of the habitats. Five species of Lutzomyia were captured: L. evansi, L. cayennensis cayennensis, L. gomezi, L. dubitansi, and L. walkeri. Lutzomyia evansi and L. gomezi presented a significant relationship in the abundance of adults indoors with respect to outdoor wind velocity. The Lutzomyia species captured showed an anthropophagic behavior with a constant activity between the 18:00 and 20:00 hrs. Lutzomyia evansi and L. gomezi are inversely proportional in relationship to wind velocity-when the wind diminishes, the activity of these species increases.

Primer informe de Lutzomyia yuilli Young &amp; Porter, 1972 y Lutzomyia triramula (Fairchild &amp; Hertig 1952) (Diptera: Psychodidae) en el departamento de Caldas, Colombia

Durante estudios de foco en varios municipios del departamento de Caldas, Colombia, donde se han presentado casos de leishmaniosis cutánea, se recolectaron nueve especies de Lutzomyia: Lutzomyia gomezi (Nitzulescu 1931), Lu. ayrozai (Barreto &amp; Coutinho 1940), Lu. panamensis (Shannon 1926), Lu. bifoliata Osorno, Morales, Osorno &amp; Hoyos, 1970, Lu. trapidoi (Farchild &amp; Hertig 1952), Lu. yuilli Young &amp; Porter, 1952, Lu. triramula (Fairchild &amp; Hertig 1952), Lu. atroclavata (Knab 1913) y Lu. trinidadensis (Newstead 1922). Dos de estos taxones constituyen nuevos registros para el departamento, Lu. yuilli del subgénero Nyssomyia, y Lu. triramula del subgénero Trichopygomyia. Los individuos de Lu. yuilli se obtuvieron mediante el uso de trampas de luz tipo Shannon y CDC en el municipio de Norcasia, mientras que los de Lu. triramula se recolectaron usando trampas de luz y adhesivas en los municipios de Norcasia y Victoria. Se discute la importancia de este hallazgo teniendo en cuenta la limitada distribución de Lu. triramula en el territorio colombiano y la capacidad vectorial de Lu. yuilli.

Evaluación de conocimientos y prácticas sobre la leishmaniasis tegumentaria en un área endémica de Venezuela

Leishmaniases constitutes a serious public health problem in many parts of the Americas. However, the populations exposed to leishmaniasis lack information about this disease. For this reason, educational assessments and interventions were deemed necessary to contribute to a greater impact of control measures. The level of knowledge and practices was evaluated for tegumentary leishmaniasis and the phlebotomine sand fly vector species. Between September 2006 and July 2007, a survey was conducted on epidemiological aspects, prevention, and control of leishmaniasis in two endemic communities-Bolero Alto and Bajo, in the municipality of Pinto Salina, Mérida state, Venezuela. It was administered to persons 7 years of age, in randomly selected houses. Collections of sand fly vectors were made indoors and around the houses. Approximately 68% of the population showed a level of knowledge on leishmaniasis considered as insufficient. The lowest level of knowledge found was on matters related to leishmaniasis transmission and prevention. Seven epidemiologically important Lutzomyia species were identified: L. youngi, L. ovallesi, L. gomezi, L. walkeri, L. panamensis, L. punctigeniculata and L. venezuelensis. The predominant species in both communities were L. youngi and L. ovallesi, constituting 55% and 24%, respectively, of the totals. The residents of the endemic communities studied had a low level of knowledge about leishmaniasis. This must be considered in the development of educational alternatives that complement control programs. A particular focus on the prevention of insect bites is recommended.

A TEN YEAR (1990-1999) SURVEY ON LEISHMANIASIS INCIDENCE IN PERNAMBUCO STATE, NORTHEASTERN BRAZIL

Diseases caused by Leishmania parasites are relatively common in rural arcas in Brazil. However, studies on eco-epidemiological aspects of the disease and its vectors, Lutzomyia species (Diptera: Psychodidae), are scarce. We studied the leishmaniasis incidence from January 1990 to December 1999 in the State of Pernambuco, Northeastem Brazil. Based on data collected by the Funda&ccedil;Ao Nacional de Sa&uacute;de, the profile of infected people, in terms of age, sex and occupation was investigated. The pliysiogeographical aspects of disease incidence were also considered. A total of 7,616 cases were recorded, of which 82.8% were cutaneous and 17.2% were visceral leishmaniasis. A higher incidence of disease was observed among men, and areas with remnants of rainforest had higher rates of infection. Children and early teenagers had a higher percentage of infection, as had adults involved in agricultural activities. Changes in vegetation composition and abundance, associatcd with an adaptative behavior by female mosquito vectors, may have contributed to an increase of leishmaniasis incidence in urban areas.