MEM INST OSWALDO CRUZ, RIO DE JANEIRO, 99(6) October 2004
PAGES: 571-574 DOI: Short communication
Feeding Preference of the Sand Flies Lutzomyia umbratilis and L. spathotrichia (Diptera: Psychodidae, Phlebotominae) in an Urban Forest Patch in the City of Manaus, Amazonas, Brazil

Liliane Coelho da Rocha Nery +, Elias S Lorosa*, Antonia Maria Ramos Franco

Laboratório de Leishmaniose e Doença de Chagas, Instituto Nacional de Pesquisas da Amazônia, 69083 Manaus, AM, Brasil
*Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro RJ, Brasil

Abstract

Precipitin tests were performed on blood meals of 199 sand flies (161 Lutzomyia umbratilis, 34 L. spathotrichia, two Lutzomyia of group shannoni, one L. anduzei) in a non-flooded upland forest on the Campus of the Universidade Federal do Amazonas. This is the second largest forest fragment in an urban setting in Brazil. Results on L. umbratilis, which is considered to be the principal leishmaniasis vector in this region, indicated rodents as its predominant blood source in contrast to previous reports in which blood meal analysis indicated that this species fed principally on Xenarthra (particularly sloths).

The city of Manaus is one of the Amazonas state townships where the number of human cases of the American cutaneous leishmaniasis (ACL) is considered to be one of the highest in Brazil. It has been increasing for the past few years comprising 57.4% (17.374/30.251) of the disease's autochthonous cases in the region (Guerra et al. 2003). The high ACL incidence occurs mainly due to the destruction of tropical forests in order to develop several settling enterprises where man exerts activities related to civil construction, hunting, fishing, and deforestation among others, thus getting in contact with the natural transmission cycles, and acquiring the disease (Araújo Filho 1981, Arias & Naiff 1981). There is a great richness of phlebotomine sand fly species in Manaus and its neighboring areas, as well as in urban forest patches including that of the Campus of the Universidade Federal do Amazonas (UFAM). Nery (2003) pointed out the occurrence of 40 phlebotomine sand fly species in this Campus alone. These included the vectors of Leishmania (Viannia) guyanensis, Lutzomyia umbratilis (Lainson et al.1976, Ward & Fraiha 1977),and L. anduzei (Arias & Freitas 1978); of L. (Leishmaniaamazonensis, L. flaviscutellata,and L. olmeca nociva (Lainson & Shaw 1968, Arias et al. 1987); L. (V.) lainsoni - L. ubiquitalis (Lainson et al. 1990, Silveira et al. 1991), and the probable vectors of L. (V.) naiffiL. ayrozai, and L. paraensis (Lainson et al. 1990).

The purpose of the present study is to determine the blood meal sources of some of the phlebotomine sand fly species found in the forest remnants of the UFAM Campus. The Campus, is located in the city of Manaus, state of Amazonas.

This Campus area, measuring nearly 800 ha and located at 03°04'34''S and 59°57'30''W, is considered to be one of the largest urban tropical sites (Carmo 2002) and Brazil's second urban forest patch (Figure). Several mammal species such as, edentates (Bradypus tridactylus, Choloepus didactylusTamandua tetradactyla, Dasypus novemcinctus, Cyclopes didactylus), primates (Pithecia pitheciaSaimiri sciureus, Saguinus bicolor bicolor),rodents(Sciurus sp., Dasyprocta agouti, D. fuliginosa, Myoprocta acouchy), and carnivorous such as Nasua nasua(Carmo 2002), inhabit this forest patch.

The landscape is comprised by plateaus, slopes and lowlands and is covered with upland non-flooded forest, grassland, campinarana, second growth and secondary forest in various succession levels (Nara & Cruz 1996, Ribeiro et al1999). The present study was conducted in upland non-flooded forest with varying degrees of environmental anthropophillic alterations. The collections were carried out in November and December 2002 from 8:00 to 10:00 a.m., by using the aspiration method at the tree base with a modified type CDC light trap on previously determined sites [areas with distinct anthropic alterations sites P1,P2, P3 (less anthropic), P5, P6 (more anthropic)]. The phlebotomine specimens were hauled to the Inpa/AM laboratory, killed at 20ºC in order to interrupt the digestive process and then kept at this same temperature up to the onset of the precipitin assays (micro-capillary).

Identification was done according to Young and Duncan (1994) taxonomic key. Females were stocked into eppendorf tubes according to species and forwarded to sent to the Fiocruz, RJ, for the precipitin test. The insects were individually ground in pH 7.0 saline solution and later centrifuged at 1800 rpm for 5 min and the eluate was examined through the in vitro reaction, by using bird and mammal anti-sera (Siqueira 1960, Lorosa et al.1998). Blood-meal fully fed females were processed testing five antigens in the obtained eluate, using anti-sera from: human being (Homo sapiens), rodent (Rattus rattus), edentate (Bradypus sp.), canids (Canis familiaris), fowl (Gallus gallus) prepared in rabbits.

A total of 199 phlebotomine sand fly blood meals were tested (Table). Of this total 151 were from an environment with lower (sites: P1, P2, P3) and 48 from one with higher anthropophillic alteration (sites: P5, P6). In the environments thought to be of lower anthopic alteration it was found that 76.2% (115) were of species L. umbratilis, 21.9% (33) L. spathotrichia, 1.3% (2) Lutzomyia of group shannoni, 0.6% (1), and L. anduzei. In the higher anthropophillic environment 95.8% (46) were of the L. umbratilis and 4.2% (1) L. spathotrichia. The L.umbratilis was abundant in the tree base, and it could be noted that the predominant feeding source for this species at the areas with lower alteration was from rodents 34% (46), followed by canids 19% (26), edentate 18% (24), human beings 16% (22), fowl 13% (18). Similarly at the area with higher alteration, canids and rodents both prevailed with 29% (13) of positivity, followed by sloth 22% (10), and human being 20% (9). The digestive tract content in 10 specimens of L. spathotrichia, reacted with the edentate anti-sera (40%), rodent and fow l 5 of each (20%), 3 of human being (12%) and 2 of canids (8%). In the more altered environment only one content of the digestive tract reacted with human being anti-serum and one with fowl. One specimen of L. anduzei collected from site P2 reacted with edentate anti-serum and two digestive tract contents of Lutzomyia of the group shannonireacted for rodent and canids. Multiple blood meals were noted in Lumbratilis (site P1 human being/fowl, dog/fowl, human being/dog, sloth/fowl, P2 dog/fowl, P3: dog/fowl and human being/fowl) and L. spathotrichia(P1 sloth/fowl, dog/rodent, rodent/fowl).

The phlebotomine feeding habit together with other factors may determine their possibility of being infected byLeishmania. With the exception of L. (L.) donovani in India, where the infection apparently occurs from man to man, and in their majority the vectors feed on human and animal reservoirs (WHO 1980). Precipitin test carried out with L. (V.) guyanensis vectors in the Manaus, AM region revealed that the predominant feeding source for L. umbratilis was edentate (sloth) followed by rodents, similar findings occurred with L. anduzei species and from the group shannoni (Christensen et al. 1982). However, we found that L. umbratilis presented higher positivity for rodent blood followed by dog and sloth. The campus area is considered an isolated forest patch within an urban center, where the occurrence of human beings as well as the presence of dogs is a common fact. In this location, the two-toed-sloth density was around 0.12 individuals/ha as reported by Carmo (2002).

All these findings suggest that the environmental changes and the consequent food offer opportunity may have had an influence on the findings obtained when compared with the correlated literature, where two-toed-sloth would be the predominant feeding source for L. umbratilis in the area of Manaus (Christensen et al. 1982). In spite of all the difficulties related to the experiment for verifying the feeding habits of L. umbratilisL. anduzeiL. spathotrichia, and Lutzomyia group shannoni, by the results of the precipitin reactions presented in this paper, it can be deduced that L. umbratilis fed preferably on rodents (34% and 29%) in the two studied areas, which differs from the results of Christensen et al. (1982) in four upland non-flooded forest areas in the city of Manaus.

A fact such as this may be related to the anthropic actions on the natural environment, greatly influencing the host's availability (Aragão 1975, Gomes et al. 1983). The feeding participation of L. spathotrichia in the transmission of ACL is discussed, verifying that their preference as a feeding source in both areas is for the blood of sloths (around 40%), as well as different species of other animals (rodents, fowl, canids), in addition to the blood of human beings (12%). We noted that these insects have the ability to perform multiple blood-meals suggesting alternative vectoring possibilities to several hosts in case one does not fulfil the complete blood-meal, as for instance the mixed blood meals of: L. umbratilis on human being/fowl, dog/fowl, human being/dog and sloth/fowl, and L.spathotrichia on sloth/fowl, dog/rodent, and rodent/fowl. The undertaking of studies on the fauna of phlebotomine sand flies in areas where environmental changes have occurred it has become a subject of great interest on account of the great ability of many of these insect species to adapt themselves to any anthropophillic environment.

 

ACKNOWLEDGEMENTS

To Roberto Dantas de Farias, Artêmio Coelho da Silva, and Francisco Lima Santos (CPCS/Inpa), for their invaluable help in undertaking the field captures sand flies. To Roberto Daibes Naiff Júnior for help in translation to English.

 

REFERENCES

Aragão MB 1975. Sobre o comportamento de alguns insetos hematófagos. Arq Biol Tecnol 18: 3-23.

Araújo Filho NA 1981. Leishmaniose tegumentar americana e o desmatamento da Amazônia. Acta Amazônica11: 187-189.

Arias JR, Freitas RA 1978. Sobre os vetores de leishmaniose cutânea na Amazônia central do Brasil. 2: incidência de flagelados em flebótomos selváticos. Acta Amazônica 8: 387-396.

Arias JR, Naiff RD 1981. The principal reservoir host of cutaneous leishmaniasis in the urban areas of Manaus, Central Amazon of Brazil. Mem Inst Oswaldo Cruz 76: 79-286.

Arias JR, Freitas RA, Naiff RD, Barrett TV 1987. Observations on the parasite Leishmania mexicana amazonensis and its natural infection of the sand fly Lutzomyia olmeca nociva. Bull PAHO 21: 48-53.

Carmo NAS 2002. Distribuição, Densidade e Padrão de Atividades de Bradypus tridactylus (Mammalia, Xenarthra) em Fragmento Florestal na Amazônia Central, MSc Thesis, Instituto Nacional de Pesquisas da Amazônia, Universidade Federal do Amazonas, Manaus, 63 pp.

Christensen HA, Arias JR, Vasquéz AM, Freitas RA 1982. Hosts of sandfly vectors of Leishmania braziliensis guyanensis in the Central Amazon of Brazil. Am J Trop Med Hyg 31: 239-242.

Gomes AC, Rabello EX, Santos JLF, Galati EAB 1983. Aspectos ecológicos da leishmaniose tegumentar americana. 3. Observações naturais sobre ritmo diário de atividades de Psychodopygus intermedius em ambiente florestal e extraflorestal. Rev Saúde Pública São Paulo 17: 23-30.

Guerra JAO, Talhari S, Paes MG, Garrido M, Talhari JM 2003. Aspectos clínicos e diagnósticos da leishmaniose tegumentar americana em militares simultaneamente expostos à infecção na Amazônia. Rev Soc Bras Med Trop 36: 587-590.

Lainson R, Shaw JJ 1968. Leishmaniasis in Brazil: I. Observations on enzootic rodent leishmaniasis _ Incrimination of Lutzomyia flaviscutellata (Mangabeira) as the vector in the Lower Amazonian Basin. Trans R Soc Trop Med Hyg 62: 385-395.

Lainson R, Shaw JJ, Silveira FT, Braga RR, Ishikawa EAY 1990. Cutaneous leishmaniasis of man due toLeishmania (Vian-nianaïffi Lainson and Shaw, 1989. Ann Parasitol Hum Comp 65: 282-284.

Lainson R, Ward RD, Shaw JJ 1976. Cutaneous leishmaniasis in North Brazil: Lutzomyia anduzei as a major vector. Trans R Soc Trop Med Hyg 70: 171-172.

Lorosa ES, Andrade RE, Santos SM, Pereira CA 1998. Estudo da infecção natural e da fonte alimentar doTriatoma sordida, (Stal, 1859), (Hemiptera-Reduvidae) na região norte de Minas Gerais, Brasil, através da reação de precipitina. Entomol Vect 5: 13-22.

Nara AK, Cruz J da 1996. Levantamento das espécies epifíticas e terrestres da família Bromeliaceae de ocorrência na Reserva Florestal do Campus da Universidade do Amazonas. Relatório Final apresentado ao CNPq/Inpa, Manaus, Amazonas, 51 pp.

Nery LCR 2003. Distribuição, Diversidade e Biologia de Flebotomíneos (Diptera: Psychodidae: Phlebotominae) da Área do Campus da Universidade Federal do Amazonas, Manaus-AM, Brasil, MSc Thesis, Instituto Nacional de Pesquisas da Amazônia, Universidade Federal do Amazonas, Manaus, 107 pp.

Ribeiro JEL. da S, Hopkins MJG, Vicentini A, Sothers CA, Costa MA da S, Brito JM de, Souza MAD de, Martins LHP, Lohamann LG, Assunção PACL, Pereira E da C, Silva CF da, Mesquita MR, Procópio LC 1999.Flora da Reserva Ducke: Guia de Identificação das Plantas Vasculares de uma Floresta de Terra-firme na Amazônia Central, Inpa-DFID, Manaus, 798 pp.

Silveira FT, Souza AAA, Lainson R, Shaw JJ, Braga RR, Ishikawa EAY 1991. Cutaneous leishmaniasis in the Amazon Region: natural infection of the sandfly Lutzomyia ubiquitalis (Psychodidae: Phlebotomine) byLeishmania (Viannialainsoni in Pará State, Brazil. Mem Inst Oswaldo Cruz 86: 127-130.

Siqueira AF 1960. Estudos sobre a reação da precipitina aplicada a identificação de sangue ingerido por triatomíneos. Rev Inst Med Trop São Paulo 2: 41-53.

Ward RD, Fraiha H 1977. Lutzomyia umbratilis n. sp. A sandfly previously identified as L. anduzei (Rozeboom, 1942) (Diptera: Psychodidae). J Med Entomol 14: 313-317.

WHO 1980. Studies on leishmaniasis vectors/reservoirs and their control in the Old World: Part IV. Asia and Pacific, VBC 80, 85 pp.

Young DG, Duncan MA 1994. Guide to the identification and geographic distribution of Lutzomyia sand flies in Mexico, the West Indies, Central and South America (Diptera: Psychodidae). Mem Amer Entomol Inst 54: 881 pp.

CONTACT US

Memórias do Instituto Oswaldo Cruz

Av. Brasil 4365, Castelo Mourisco
sala 201, Manguinhos, 21040-900
Rio de Janeiro, RJ, Brazil

Tel.: +55-21-2562-1222

This e-mail address is being protected from spambots. You need JavaScript enabled to view it.

twitterfacebook

SUPPORT PROGRAM

marca fiocruzmarca brasil
marca faperjmarca cnpqmarca capes n marca cope

and diabetes. Erection dysfunction or ED is certainly one of mens most usual problem. It changes buy tadalafil 60mg A common drug is actually an imitation of its manufacturer twin. Both ought to be same in female cialis 20mg Long Phrase Viagra Use Fundamentally Damages Sex Lives This discount cialis canada Equally so, theres something to be said for the wonder of the second, captured forever on picture or a buy cheap cialis People extremely annoyed that they could only get three weeks at a time, Bunker noted. Retired persons cheap pharmacy These types of matters are possibly to being identified as having a result of cancer buy cialis 40mg - Yoghourt - fat-free simply Physical causes: Buying generic medicines now has been cheap generic cialis Herbaceous plants like nigrum and tribulus are well-known for his or her qualities in defeating impotence, which tadalafil 10mg It is not hard to consider Cialis that is generic. Most men start with one-10 mg dosage each purchase cialis Tadalafil quickly gained the moniker of weekender in Paris due to the fabulous results. The bash freaks buy female cialis