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1.
Methods of finding larvae and pupae of phlebotomine sandflies (Diptera: Psychodidae) are described and the known types of breeding sites used by sandflies are listed. Three ways of detecting sandfly breeding places are the use of emergence traps placed over potential sources to catch newly emerged adult sandflies; flotation of larvae and pupae from soil, etc., and desiccation of media to drive out the larvae. Even so, remarkably little information is available on the ecology of the developmental stages of sandflies, despite their importance as vectors of Leishmania, Bartonella and phleboviruses affecting humans and other vertebrates in warmers parts of the world. Regarding the proven or suspected vectors of leishmaniases, information on breeding sites is available for only 15 out of 29 species of sandflies involved in the Old World and 12 out of 44 species of sandflies involved in the Americas, representing approximately 3% of the known species of Phlebotominae. Ecotopes occupied by immature phlebotomines are usually organically rich moist soils, such as the rain forest floor (Lutzomyia intermedia, Lu. umbratilis, Lu. whitmani in the Amazon; Lu. gomezi, Lu. panamensis, Lu. trapidoi in Panama), or contaminated soil of animal shelters (Lu. longipalpis s.l. in South America, Phlebotomus argentipes in India; P. chinensis in China; P. ariasi, P. perfiliewi, P. perniciosus in Europe). Developmental stages of some species (P. langeroni and P. martini in Africa; P. papatasi in Eurasia; Lu. longipalpis s.l. in South America), have been found in a wide range of ecotopes, and many species of sandflies employ rodent burrows as breeding sites, although the importance of this niche is unclear. Larvae of some phlebotomines have been found in what appear to be specialized niches such as Lu. ovallesi on buttress roots of trees in Panama; P. celiae in termite hills in Kenya; P. longipes and P. pedifer in caves and among rocks in East Africa. Old World species found as immatures in the earthen floor of human habitations include P. argentipes, P. chinensis, P. martini and P. papatasi. Much more information on sandfly breeding sites is required to facilitate their control by source reduction.  相似文献   

2.
Several characteristics of dispersing and non-dispersing Phlebotomus papatasi (Scopoli) were quantified and compared. The majority of dispersing sandflies, trapped crossing fallow fields, were females (68.5% v. 51.1%); of the dispersing females, 55.4% were parous, 48.1% were inseminated and 11.6% were gravid. In the population of sandflies sampled exiting from burrows of the sand rat Psammomys obesus Cretschmar, these categories, respectively, represented 39%, 90% and 26% of the females examined. Leishmania promastigotes were found in 9% of females exiting from P. obesus burrows, and in 2.7% of the dispersing females. The anthrone test established that the reason for activity of gravid females is sugar feeding. These females do not disperse and are suitable targets for future control measures.  相似文献   

3.
The bionomics of phlebotomine sandflies (Diptera: Psychodidae) were studied for three years (2001-2003) in the Galilee focus of cutaneous leishmaniasis in northern Israel, where the causative Leishmania tropica (Kinetoplastida: Trypanosomatidae) is transmitted by Phlebotomus (Adlerius) arabicus Theodor and Phlebotomus (Paraphlebotomus) sergenti Parrot, comprising 22% and 8%, respectively, of the local sandfly fauna sampled by light traps. The predominant species overall was Phlebotomus (Larroussius) tobbi Adler & Theodor (51%) with lesser numbers of Phlebotomus (Adlerius) simici Theodor (11%), Phlebotomus (Larroussius) syriacus Adler & Theodor (5%), Phlebotomus (Larroussius) perfiliewi Perfil'ev (3%) and Phlebotomus (Phlebotomus) papatasi Scopoli (0.05%). Sandfly adult populations were prevalent from April to November and peaked between June and August, being more abundant through the summer in irrigated habitats, such as gardens and orchards, than in open grassland. Of the two cutaneous leishmaniasis vectors, P. sergenti preferred boulder mounds located at the outskirts of settlements, whereas P. arabicus was more abundant overall and near houses in particular. Females of all these sandfly species displayed a peak of activity after sunset (20.00-22.00 hours), whereas activity of males persisted longer through the night. Another slight increase in activity was noted before dawn (02.00-04.00 hours). Phlebotomus arabicus appears to be the main vector of L. tropica in the Galilee focus, due to its denser populations, more endophily and preference for peridomestic habitats than shown by P. sergenti in northern Israel.  相似文献   

4.
Abstract. During three field surveys of phlebotomine sandflies in the region of Sessa, Minor Malcantone, southern Switzerland, annually 1987-89, Phlebotomus pemiciosus and P.mascittii were caught regularly by means of light traps, but only when the traps were in close association with humans. The most productive catching sites were in the middle of Sessa village, in basements or partially closed shelters in the immediate vicinity of human dwellings. All catching sites outside the village were negative. The only other sandfly species caught was Sergentomyia minuta, four specimens only. P.pemiciosus and P.mascittii always occurred together and were found to feed - at least occasionally – on human blood. Glucose and fructose were identified in wild-caught sandflies of both species. A breeding place of P.mascittii was identified in the basement of a house in the middle of Sessa. Analyses of soil samples revealed moderately loamy humus with a slightly acidic pH (5.6).  相似文献   

5.
A total of 131 phlebotomine Algerian sandflies have been processed in the present study. They belong to the species Phlebotomus bergeroti, Phlebotomus alexandri, Phlebotomus sergenti, Phlebotomus chabaudi, Phlebotomus riouxi, Phlebotomus perniciosus, Phlebotomus longicuspis, Phlebotomus perfiliewi, Phlebotomus ariasi, Phlebotomus chadlii, Sergentomyia fallax, Sergentomyia minuta, Sergentomyia antennata, Sergentomyia schwetzi, Sergentomyia clydei, Sergentomyia christophersi and Grassomyia dreyfussi. They have been characterised by sequencing of a part of the cytochrome b (cyt b), t RNA serine and NADH1 on the one hand and of the cytochrome C oxidase I of the mitochondrial DNA (mtDNA) on the other hand. Our study highlights two sympatric populations within P. sergenti in the area of its type-locality and new haplotypes of P. perniciosus and P. longicuspis without recording the specimens called lcx previously found in North Africa. We tried to use a polymerase chain reaction-restriction fragment length polymorphism method based on a combined double digestion of each marker. These method is not interesting to identify sandflies all over the Mediterranean Basin.  相似文献   

6.
ABSTRACT. The visceral leishmaniasis (VL) vector Phlebotomus argentipes Annandale & Brunetti is widely distributed throughout the Indian sub-continent and S.E. Asia. The absence of VL in areas such as Sri Lanka has been attributed to the zoophilic nature of P.argentipes , since they were not recorded biting man.
Field studies on P. argentipes were undertaken in the central highlands of Sri Lanka, near Kandy, in May 1988. Male sandflies outnumbered females on cows by 19:1, and were regularly spaced at all densities. This behaviour is considered analagous to swarming in other Nematocera. However, all-night human-biting catches show the biting rate to be similar (mean=8.4, range 2–25 bites per night over ten consecutive nights) to that in N.E. India where VL is endemic. This anthropophagy was maintained during laboratory colonization.  相似文献   

7.
Abstract. Bloodmeal digestion in midguts of the sandflies Phlebotomus papatasi and Phlebotomus langeroni (Diptera: Psychodidae) was investigated in optimized assays to detect general protease, trypsin and aminopeptidase activities using synthetic substrates. Optimal activity occurred at pH 8-9 for all enzymes examined in both species. Protease activity peaked at 24-34h post human bloodmeal in midguts of P.papatasi and 34-48h in P'.langeroni; all endo- and exoprotease activities were completed by 50 h in P.papatasi compared to 72 h in P. langeroni. Hydrolysis of two chymotrypsin substrates was <2% of trypsin activity in both species. Aminopeptidase activity was associated mainly with the midgut wall, whereas trypsin activity was confined to the midgut lumen. A feature of digestion in P.langeroni was the high level of aminopeptidase recorded within 10h of the bloodmeal.  相似文献   

8.
In many foci of zoonotic visceral leishmaniasis (ZVL), domestic dogs are important reservoir hosts of the causative Leishmania parasites transmitted by phlebotomine sandflies (Diptera: Psychodidae). We tested the protective value of impregnated dog collars (20 g plastic containing deltamethrin 800 mg ai) against Phlebotomus papatasi (Scopoli) sandflies in Iran. For each assay, the dog was sedated and caged in a net with 70-100 wild-caught sandflies overnight (23.30-06.30 hours). Dogs wearing the collars were bitten by approximately 80% fewer sandflies than before collars were fitted, i.e. 51% vs. 11% of hungry female flies exposed. Sandfly mortality rates following 20 h exposure to dogs with collars (18%) or without collars (17%) were not significantly different. Effects of collars were tested when dogs had been wearing them for 8 days. A previous trial against the sandfly P. perniciosus Newstead in France, using smaller dogs, showed that effects of such collars were not fully realized until they had been worn for 2 weeks or more; they remained effective for at least 8 months and killed significant proportions of the sandflies exposed. Present results with P. papatasi, confirming that this simple device provides effective protection against sandflies, are considered sufficiently encouraging to justify a community-wide field trial of deltamethrin-impregnated dog collars against ZVL vector sandflies in Iran.  相似文献   

9.
The eggshell structure of four sandfly species: Phlebotomus perniciosus Newstead, P.perfiliewi Parrot, P.papatasi Scopoli and P.duboscqi Neveu-Lemaire, was examined by scanning and transmission electron microscopy (SEM and TEM). At the TEM level, the eggshell appears to have a homogeneous vitelline envelope and a thick chorion. At SEM level, the eggshell of all species is characterized by the outer chorion forming a series of fifteen to twenty longitudinal sinuous ridges, cross-linked in places to form a pattern of polygons, each line of the chorion consisting of columns arranged in a palisade. The aeropyle region of the egg is described for the first time in phlebotomine sandflies. Specific characters of the eggshell topography are described for distinguishing between these and other species of Phlebotomus.  相似文献   

10.
In Eurasia, phlebotomine sandflies of the subgenus Adlerius (Diptera: Psychodidae) comprise about 20 known species. Some are suspected vectors of visceral leishmaniasis (VL) and at least one species has been implicated as a vector of cutaneous leishmaniasis (CL). We tested Phlebotomus (Adlerius) halepensis Theodor (Jordan strain) for CL vector competence, compared with three standard vectors: Phlebotomus (Phlebotomus) duboscqi N-L. from Senegal, Phlebotomus (Paraphlebotomus) sergenti Parrot from Turkey and the Neotropical Lutzomyia longipalpis (L. & N) (Jacobina strain). Sandfly females were membrane-fed on amastigote suspensions of Leishmania major Y. & S. and Le. tropica (Wright) (Kinetoplastida: Trypanosomatidae) and examined for parasite development 3, 6 and 10 days post-infection. Phlebotomus halepensis showed high susceptibility to both leishmanias, supporting typical suprapylarian parasite development similar to the other vectors. Phlebotomus halepensis infection rates were approximately 90% for Le. major and approximately 80% for Le. tropica, with high parasite densities. Development of infections was relatively fast, colonizing the thoracic midgut by 6 days post-bloodmeal in every case and reaching the stomodeal valve in >80% of flies. In late-stage infections, 10 days post-bloodmeal, nearly all P. halepensis females had cardia and stomodeal valve filled with very high numbers of parasites and some Le. tropica-infected females had promastigotes in the pharynx and proboscis. Host choice experiments in the laboratory showed that P. halepensis females fed readily on rat or rabbit and preferred the human forearm. In view of its vector competence and partial anthropophily, we infer that P. halepensis is a potential vector of cutaneous as well as visceral leishmaniases.  相似文献   

11.
Cutaneous leishmaniasis (CL) is a neglected clinical form of public health importance that is quite prevalent in the northern and eastern parts of Egypt. A comprehensive study over seven years (January 2005-December 2011) was conducted to track CL transmission with respect to both sandfly vectors and animal reservoirs. The study identified six sandfly species collected from different districts in North Sinai: Phlebotomus papatasi, Phlebotomus kazeruni, Phlebotomus sergenti, Phlebotomus alexandri, Sergentomyia antennata and Sergentomyia clydei. Leishmania (-)-like flagellates were identified in 15 P. papatasi individuals (0.5% of 3,008 dissected females). Rodent populations were sampled in the same districts where sandflies were collected and eight species were identified: Rattus norvegicus (n = 39), Rattus rattus frugivorous (n = 13), Rattus rattus alexandrinus (n = 4), Gerbillus pyramidum floweri (n = 38), Gerbillus andersoni (n = 28), Mus musculus (n = 5), Meriones sacramenti (n = 22) and Meriones crassus (n = 10). Thirty-two rodents were found to be positive for Leishmania infection (20.12% of 159 examined rodents). Only Leishmania major was isolated and identified in 100% of the parasite samples. The diversity of both the vector and rodent populations was examined using diversity indices and clustering approaches.  相似文献   

12.
Abstract. Dog collars made of PVC plastic impregnated with the pyrethroid insecticide deltamethrin at 40 mg/g were investigated for their protective efficacy against phlebotomine sandflies. Collared dogs were kept separately (two untreated control dogs lived together) in outdoor enclosures, each with a kennel, in the Cevennes, southern France. To measure sandfly mortality and anti-feeding effects due to the deltamethrin-impregnated collars worn continuously by the dogs for up to 8 months, each dog was periodically sedated and exposed for 2h to 150–200 laboratory-reared Phlebotomus perniciosus females (plus c. 25 males) inside a net (1.2m square, 1.8 m high) indoors. After dogs were removed from the nets, allowed to recover and returned to their kennels, any dead sandflies were collected from inside the net and counted. Surviving flies were kept overnight, then scored according to whether they were still alive or dead, unfed or blood-fed. From tests 2, 3, 4, 13, 20, 26 and 34 weeks after the dogs began wearing collars, the overall numbers of blood-fed female sandflies recaptured were 75 from two dogs with collars, compared with 1911 from two collarless dogs. Thus, for every 100 flies which fed on collarless dogs, only 4 fed on collared dogs, i.e. the collars protected dogs from 96% of the bites and this activity was maintained for up to 34 weeks. During the same period, the percentage of recaptured female sandflies that had fed on collared dogs was 0–12% compared to 55–95% on collarless dogs. Immediately after dogs were taken out of the nets, 21–60% of flies confined with the collared dogs were found dead, compared to 0–12% with the controls. It is concluded that, at least in the Mediterranean subregion, this insecticidal collar would protect a dog from the majority of sandfly bites and retain a killing effect for a complete sandfly season. Moreover, it seems likely that the use of collars on all dogs in a focus of Leishmania infantum would reduce contact between sandfly vectors and canine reservoir hosts sufficiently to diminish the risk of infection for humans as well as dogs.  相似文献   

13.
The juvenile hormone analogues methoprene and pyriproxyfen were evaluated as rodent feed-through insecticides for control of immature stages of the sandfly Phlebotomus papatasi Scopoli (Diptera: Psychodidae). The development and survival of P. papatasi second-instar larvae fed faeces from Syrian hamsters, Mesocricetus auratus, that had been fed a diet containing methoprene (0, 9.788, 97.88 or 978.8 p.p.m.) or pyriproxyfen (0, 9.82, 98.2 or 982 p.p.m.) were evaluated. The faeces of methoprene-treated hamsters greatly reduced the percentage of larvae that pupated at all concentrations tested and prevented adult emergence at all but the lowest concentration (9.788 p.p.m.). Pyriproxyfen prevented both pupation and adult emergence at all concentrations tested. The results of this study suggest that a control strategy using rodent baits containing juvenile hormone analogues to control phlebotomine sandflies that live in rodent burrows and feed on rodent faeces may be possible. As rodent reservoirs and vectors of Leishmania major live in close association in many parts of the Middle East, control of the transmission of the agent of zoonotic cutaneous leishmaniasis may also be possible.  相似文献   

14.
The patchy geographical distributions of classic Kaposi's sarcoma (KS) and human herpesvirus type 8 (HHV-8), better known as Kaposi's sarcoma-associated herpesvirus (KSHV) remain unexplained. It has been proposed that certain species of bloodsucking insects ('promoter arthropods') promote the reactivation of HHV-8/KSHV and facilitate both HHV-8/KSHV transmission and KS development. This hypothesis was tested by sampling the presence and density of human-biting Diptera with CDC light traps in two areas of Sardinia with contrasting incidence rates of classic KS. In total, 11 030 specimens (99.9% sandflies and 0.1% mosquitoes) belonging to 10 species were collected from 40 rural sites. Five of these species are considered to be possible promoter arthropods because of the irritation their bites cause: Phlebotomus perniciosus Newstead; Phlebotomus perfiliewi Parrot (Diptera: Psychodidae); Aedes berlandi Seguy; Culiseta annulata (Schrank) and Culex theileri Theobald (Diptera: Culicidae). Five species are probable 'non-promoters' because their bites are not particularly irritating: Culiseta longiareolata (Macquart); Culex pipiens s.l .; Anopheles algeriensis Theobald; Anopheles maculipennis s.l. , and Anopheles plumbeus Stephens. A significant correlation was found between the geographical distribution of promoter arthropods and incidence rates of KS (Spearman's r = 0.59 ,P < 0.01). Promoter arthropods were more likely to be caught in areas with cutaneous leishmaniasis and a past high prevalence of malaria, and in areas of limestone, acid volcanic soil and cereal cultivation. The study supports the association between promoter arthropods and classic KS, which may explain the geographic variability of KS and HHV-8/KSHV, and highlights the links with a number of variables previously associated with the incidence of KS.  相似文献   

15.
The cuticular hydrocarbons of Phlebotomus perfiliewi Parrot from representative localities on both sides of Italy show contrasts which support the view of Ward et al., (1981) that there are distinguishable populations of this sandfly on the Adriatic and Tyrrhenian coasts. It is suggested that the Appennine mountains form a barrier between the Adriatic and Tyrrhenian populations. A third distinct hydrocarbon type of P. perfiliewi was detected in Calabria, southern Italy, where contact between the Adriatic and Tyrrhenian types of flies is most likely to occur. P. perfiliewi from a trans-Appennine pass were also of the Calabrian hydrocarbon type. These hydrocarbon contrasts between allopatric populations of P. perfiliewi may result from clinical variation across the Appennines, associated with different host preferences, or they may represent apomictic populations with differential mate recognition systems.  相似文献   

16.
Compounds from the odour-producing glands of the fox Vulpes vulpes were collected. This complex mixture of compounds was used to stimulate the ‘ascoid’ olfactory organs of female sandflies in single sensillum and gas chromatography-linked single sensillum recordings. Sixteen of these compounds were identified using gas chromatography-linked mass spectrometry and amounts present were determined. The compounds fell into four organic classes: ketones, carboxylic acids, alcohols and aldehydes. Specific neurones present in the ascoid sensillum that responded to each of these classes of compound were characterized. A bioassay chamber was developed that gave female sandflies the choice of two odour sources. Female sandflies were attracted upwind by fox odour and were trapped in closer proximity to the fox odour port than the control port. Synthetic compounds were recombined in appropriate quantities to mimic the fox odour. In this bioassay, the synthetic blend attracted sandflies upwind, and again they were caught closer to the test port than the control port. Furthermore, the synthetic fox odour induced an electrophysiological response from neurones in the ascoid sensillum that was very similar to that induced by natural fox odour. No synthetic compound alone induced the same behavioural response from sandflies as did whole fox odour. However, benzaldehyde, 4-hydroxy-4-methyl-2-pentanone and 4-methyl-2-pentanone alone did cause sandflies to fly upwind and to be caught closer to the test port than the control.  相似文献   

17.
This study was conducted to investigate the diversity of sandflies (Psychodidae: Phlebotominae) and the incidence of leishmaniasis in three villages of North Waziristan Agency, Pakistan. Sandflies were sampled monthly during 2012, at dusk and dawn, in selected indoor habitats including both bedrooms and animal sheds using a knock‐down spray catch method. A total of 3687 sandflies were collected, including 1444 individuals in Drezanda, 1193 in Damdil and 1050 in Dattakhel. This study revealed 14 species of two genera, Phlebotomus (Phlebotomus sergenti, Phlebotomus papatasi, Phlebotomus caucasicus, Phlebotomus kazeruni, Phlebotomus alexandri and Phlebotomus salehi) and Sergentomyia (Sergentomyia dentate, Sergentomyia baghdadis, Sergentomyia babu, Sergentomyia theodori, Sergentomyia sumbarica, Sergentomyia dreyfussitur kestanica, Sergentomyia hogsoni pawlowskyi and Sergentomyia fallax afghanica) (both: Diptera: Psychodidae). Phlebotomus sergenti was the most abundant species (42.1%), followed by S. dentata (17.7%) and S. baghdadis (17.4%). The number of males collected represented about twice that of female flies, and the maximum number was collected in July, followed by August. The determination of the species composition of sandfly populations, seasonal variations, relative abundances and estimations of infection in the vector population may provide information about the dynamics of leishmaniasis transmission that is useful in planning vector control activities.  相似文献   

18.
Epidemiological field studies on leishmaniasis have been hampered by the laborious, and often inefficient, methods used to assess the rates of infection of sandfly vectors (Diptera; Phlebotominae) by species of the causative disease organisms, protozoal parasites of the genus Leishmania (Kinetoplastida; Trypanosomatidae). We report the rapid and accurate identification of both sandfly vector (Phlebotomus (Phlebotomus) papatasi (Scopoli] and infecting Leishmania major Yakimov & Schokov by DNA hybridizations to squash-blotted sandflies. Large numbers of whole (infected) sandflies can be quickly squashed on to nylon hybridization filters and (following standard procedures) the filter-bound DNA can be hybridized sequentially to cloned, multicopy genomic sequences that are specific for species of Leishmania (kinetoplast DNA) or for the sandfly (ribosomal (r) DNA). Our sandfly probe consists of a 3.2 kb fragment of the intergenic 'non-transcribed' spacer of rDNA of P. papatasi that we have detected only in this species: it is present in all six geographically isolated populations tested (from Tunisia through to India) but cannot be detected in the morphologically similar P. (Phlebotomus) duboscqi Neveu-Lemaire, the vector of Leishmania major south of the Sahara; it also cannot be detected in Phlebotomus species of the subgenera Larroussius and Paraphlebotomus that together with P. papatasi are the dominant man-biting sandflies in north African foci of zoonotic cutaneous leishmaniasis, where (as in many arid regions of western Asia) P. papatasi is believed to be the sole vector of L. major.  相似文献   

19.
Abstract.  The control of phlebotomine sandflies (Diptera: Psychodidae), the vectors of leishmaniasis, is directed mostly against adults as larvae develop in unknown or inaccessible habitats. In the current study we tested geraniol, a natural plant-derived product, as a space repellent and the synthetic pyrethroid prallethrin as a diffusible insecticide. Geraniol was dispersed in the air using diffusers with an electric fan and prallethrin was evaporated using electrically heated evaporators. Both substances were tested in inhabited bedrooms and in tents. Geraniol failed to effect significant reductions in the numbers of either Phlebotomus papatasi Scopoli in rooms or Phlebotomus sergenti Parrot in tents. In laboratory experiments, geraniol proved ineffective in preventing sandflies from feeding. By contrast, prallethrin was highly effective in reducing the number of sandflies in rooms as well as in tents. Exposure of sandflies to prallethrin in laboratory experiments caused 97% mortality rates. Both prallethrin and, to a lesser extent, geraniol reduced the number of Culex mosquitoes captured in tents. Electric liquid-vaporizers with 1.5% prallethrin are highly effective in protecting people from sandfly bites in confined spaces and may be useful in combating cutaneous leishmaniasis.  相似文献   

20.
Adult sandflies (Diptera: Psychodidae) of the genus Phlebotomus and of the subgenus Larroussius were collected with sticky traps from thirty-four localities in central and south-western Morocco. Four Larroussius species were present in this area, Phlebotomus perniciosus Newstead, being the most widespread and abundant species particularly in the mountainous area, was sympatric with the closely related species Phlebotomus longicuspis Nitzulescu. Only one male of P. perniciosus displayed the bifid copulatory valves characteristic of the species. All specimens showed copulatory valves curved at their apex. The number of coxite hairs is a taxonomical tool that differentiates this morph of P. perniciosus from P. longicuspis. Phlebotomus ariasi Tonnoir was collected from six mountainous stations. Phlebotomus mariae Rioux et al. was scarce; only five males were collected and were often associated with P. ariasi.  相似文献   

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