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1.
The high proportion of cases of cutaneous leishmaniasis reported amongst residents in the city of Bandeirantes, in the state of Paraná, Brazil, led the authors to investigate the phlebotomine fauna in both urban and rural environments. The sandflies were captured with automatic light traps from 07:00 pm-07:00 am fortnightly in 11 urban peridomiciles from April 2008-March 2009 and monthly in three ecotopes within four rural localities from April 2009-March 2010. In one of these latter localities, sandfly capture was conducted with white/black Shannon traps during each of three seasons: spring, summer and fall. A total of 5,729 sandflies of 17 species were captured. Nyssomyia neivai (46.7%) and Nyssomyia whitmani (35.3%) were the predominant species. In this study, 3,865 specimens were captured with automatic light traps: 22 (0.083 sandflies/trap) in the urban areas and 3,843 (26.69 sandflies/trap) in the rural areas. Ny. neivai was predominant in urban (68.2%) and rural (42.8%) areas. A total of 1,864 specimens were captured with the white/black Shannon traps and Ny. neivai (54.5%) and Ny. whitmani (31.4%) were the predominant species captured. The small numbers of sandflies captured in the urban areas suggest that the transmission of Leishmania has occurred in the rural area due to Ny. neivai and Ny. whitmani as the probable vectors.  相似文献   

2.
Sandflies are holometabolous insects that are of great epidemiological importance in the neotropical region as vectors of leishmaniases. Caves are ecotopes that significantly differ from external environments and, among the insects that live or visit their internal area and adjacent environment, sandflies are commonly found. Based on this context, the objective of this work was to examine the period of activity of sandflies in the cave environment in the aphotic zone. Thus, four sandfly captures were conducted, one in each season of the year, in a cave where studies on the bioecological aspects of sandfly fauna have been conducted since 2008. In this same study, we have also noticed the presence of flagellates in some captured females. Catches were carried out for 24 hours using a Shannon trap, light bait, and cave walls were actively searched. We collected a total of 638 sandflies, representing 11 species. The most abundant species and with more intense period of activity were, in descending order: Lu. cavernicola (62%), Ev. spelunca (16%) and Ev. sallesi (14%). A total of 69 females were dissected to check for natural infection, and in five specimens we found living flagellated forms: two Ev. spelunca, two Ev. sallesi and one Sc. sordellii. This study shows that the activity of some species caught in the aphotic zone of the cave, especially Lu. cavernicola, differs from what has already been reported in previous sandfly captures, which are almost always conducted at night and during twilight. The existence of sandflies that were naturally infected with flagellates and the lack of awareness regarding the behaviour of sandflies in cave environments are strong indicators of the need for further study on this group of insects in this ecotope, as a safety measure to protect the visitors of such environment.  相似文献   

3.
The composition and seasonal occurrence of sandflies were investigated in coffee agroecosystems in the Soconusco region of Chiapas, Mexico. Insect sampling was performed on three plantations located at different altitudes: Finca Guadalupe Zajú [1,000 m above sea level (a.s.l.)], Finca Argovia (613 m a.s.l.) and Teotihuacán del Valle (429 m a.s.l.). Sandflies were sampled monthly from August 2007-July 2008 using three sampling methods: Shannon traps, CDC miniature light traps and Disney traps. Sampling was conducted for 3 h during three consecutive nights, beginning at sunset. A total of 4,387 sandflies were collected during the course of the study: 2,718 individuals in Finca Guadalupe Zajú, 605 in Finca Argovia and 1,064 in Teotihuacán del Valle. The Shannon traps captured 94.3% of the total sandflies, while the CDC light traps and Disney traps captured 4.9% and 0.8%, respectively. More females than males were collected at all sites. While the number of sandflies captured was positively correlated with temperature and relative humidity, a negative correlation was observed between sandfly numbers and rainfall. Five species of sandflies were captured: Lutzomyia cruciata , Lutzomyia texana , Lutzomyia ovallesi , Lutzomyia cratifer / undulata and Brumptomyia sp. Lu. cruciata , constituting 98.8% of the total, was the most abundant species. None of the captured sandflies was infected with Leishmania spp.  相似文献   

4.
Abstract. Recently the sandfly Phlebotomus guggisbergi was found to be a vector of Leishmania tropica causing cutaneous leishmaniasis in the Laikipia focus, Kenya, but extensive searches have shed no light on the identity of the rural reservoir host(s). In order to discover more about the biology of the vector, a host feeding preference study was conducted on wild sandflies in their natural cave environment over a 6-month period. Solid state Army miniature (SSAM) traps, without light bulb, were suspended over cages with potential hosts or an empty cage control. The animals tested included sheep, goat, dog, cat, hamster, rabbit, giant rat (Cricetomys gambianus), crested rat (Lophiomys imhausi) and rock hyrax (Procavia capensis), all of which (except hamsters) are normally found in the vicinity of the study site. Sandfly collections from traps baited with goat, sheep, cat, dog, rabbit, or wild rodent species were significantly higher than the control, whereas trap collections with hamster and rock hyrax were not significantly different from the control. Numbers of sandflies collected from the goat, sheep and cat were significantly greater than from the rabbit and rodents. The sex ratio also varied between collections: larger animals attracted a higher proportion of female P.guggisbergi than did the smaller animals (P>0.05). Therefore greater emphasis should be placed on surveying larger animals to assess their status as reservoir hosts for L.tropica in Kenya.  相似文献   

5.
Abstract. A study was carried out in the Peruvian Andes to test the suitability of CDC light traps for monitoring changes in the human-landing rate of endophagic phlebotomine sandflies, following house-spraying with pyrethroid insecticide. On four pairs of consecutive nights, sandflies were caught inside eight sprayed and eight unsprayed houses, either by human bait or by CDC light traps. The sandflies collected were Lutzomyia verrucarum (97%) and Lu. peruensis (3%), both probable vectors of Leishmania peruviana , and the species composition was unaffected by house-spraying. A non-linear relationship was detected between light-trap and human-bait catches, but the relationship did not diverge significantly from linearity within the range of sandfly abundance found in most houses in the endemic area (i.e. between 3 and 200 sandflies/house-night), and did not differ significantly between sprayed and unsprayed houses. However, light trap catches had a significantly lower proportion of blood-fed females in sprayed than in unsprayed houses, probably due to an insecticidal effect on post-blood-feeding behaviour. The proportion of Lu. verrucarum was significantly higher in light trap than in human bait catches, indicating that Lu. peruensis is either more anthropophilic or less phototropic than Lu. verrucarum.  相似文献   

6.
During a research project aimed at the study of the Culicinae fauna of Gabon and carried out in the National Park of La Lopé, we captured an unknown sandfly male specimen (genus Phlebotomus) by CDC miniature light trap belonging to a new species for Science. Furthermore, the originality of his genitalia does not allow us to include this species in one of the existing subgenus, thus in this paper we propose the creation of a new subgenus, as Phlebotomus (Legeromyia) multihamatus sp. nov., subg. nov. described from the National Park of La Lopé, through one male captured with CDC miniature light trap. A new species and a new subgenus of sandfly is characterised by a short style with three spines, a paramere wearing a basal hook as well as a basal pouch and the absence of basal lobe on the coxite. The originality of the genitalia of the male gives way to discussion about potential primary homologies between P. multihamatus sp. nov. and Phlebotomus (Abonnencius) fortunatarum, Phlebotomus (Anaphlebotomus) stantoni and Phlebotomus (Euphlebotomus) argentipes, which should be verified for future studies. The discovery of this new species in Gabon must encourage the study of sandflies in this country.  相似文献   

7.
The efficacy of light traps for collecting sandflies (Diptera: Psychodidae) varies both inter-specifically and intra-specifically (by gender and physiological status) as a result of significant differences in phototropic and other behavioural characteristics. The efficacy of miniature CDC light traps for collecting Phlebotomus argentipes Annandale & Brunetti, a vector of Leishmania donovani Laveran & Mesnil (Kinetoplastida: Trypanosomatidae), was assessed in the Indian state of Bihar. Sandflies were collected during the night from 16 houses in each of three villages over 3 months (four times at fortnightly intervals) using CDC light traps indoors, and by aspirator collection (carried out by one person for 30 min/house) from the walls of the same houses the following morning. Incidence rate ratios (IRRs) between CDC light trap collections and aspirator collections were obtained through a negative binomial regression with household as random effect. CDC light traps were especially effective in catching males (IRR 3.08, 95% confidence interval [CI] 2.12-4.46) and unfed females (IRR 3.50, 95% CI 2.37-5.16) of P. argentipes, and to a lesser extent gravids (IRR 1.77, 95% CI 1.07-2.93). However, only a relatively small proportion of all blood-fed P. argentipes were collected by light trap (IRR 0.45, 95% CI 0.28-0.73). Despite its limitations in collecting blood-fed female sandflies, the CDC light trap appears to trap a sufficient proportion of the indoor population of sandflies for sampling purposes, and as this light trap is also more convenient and more easily standardized than the aspirator method, we conclude that it is the most efficient method for monitoring P. argentipes populations in the Indian subcontinent.  相似文献   

8.
In north-central Venezuela Lutzomyia gomezi and Lu. ovallesi are the main endophilic/anthropophilic species of phlebotomine sandflies implicated as vectors of cutaneous leishmaniasis (CL). Lutzomyia ovallesi has been found infected with Leishmania braziliensis (1.2%) and less often with Le. mexicana (0.07%), while Le. braziliensis infections have also been found in Lu. gomezi (0.47%). We investigated population densities of these sandflies using two sampling methods with four series of collections between January 1991 and March 1995 at El Ingenio, Miranda State. All-night outdoor collections from a Shannon trap were correlated with indoor collections from CDC light–traps by linear regression, which proved to be statistically significant for both species. Estimated numbers of female sandflies per house per night were found to be proportional to monthly precipitation (i.e. rainfall), with a lag time of seven months for Lu. ovallesi and of six months for Lu. gomezi . Predominance of Lu. ovallesi over Lu. gomezi ( c. 10 :1 ) was observed throughout the year, with the number of infected females estimated as 0.043 ± 0.047 Lu. ovallesi and 0.0085 ± 0.0124 Lu. gomezi per CDC trap per house per night (ratio ∼ 5:1). The mean rate of new CL cases per house per year and sandfly abundance were correlated by linear regression, showing a statistically significant relationship for Lu. ovallesi but not for Lu. gomezi . The negative intercept indicated that, on average, the CDC trap density exceeds 800 Lu. ovallesi females/house/year before new CL cases occur at El Ingenio.  相似文献   

9.
ObjectiveTo measure the impact on transmission of leishmaniasis of curtains impregnated with insecticide.DesignCluster randomised controlled trial: household interview survey, observational study of people''s behaviour, entomological study with light trap captures of sandflies inside houses.Setting14 urban sectors in Trujillo, Venezuela.Participants2913 inhabitants of 569 houses.InterventionSectors were paired according to their 12 month cumulative incidence of cutaneous leishmaniasis, one sector in each pair was randomly allocated to receive polyester curtains impregnated with lambdacyhalothrin (intervention group) while the other sector received curtains without insecticide or no curtains (control groups). After 12 months a follow up household survey was conducted.ResultsTransmission of cutaneous leishmaniasis occurred mainly in the domestic setting, with the incidence over 12 months of 4%. The mean number of sandflies per trap per night was 16. After follow up the 12 month incidence of cutaneous leishmaniasis was 0% in the intervention group and 8% in the six pairs in the control group that received unimpregnated curtains (mean difference 8, 95% confidence interval 4.22 to 11.78; P=0.001). There were significantly fewer sandflies in the intervention group (2 v 15, mean difference 13 sandflies per trap; 9 to 17; P<0.001).ConclusionCurtains impregnated with insecticide provide a high degree of protection against indoor transmission of cutaneous leishmaniasis.

What is already known on this topic

The transmission of cutaneous leishmaniasis is increasingly in urban and domestic settingsHouse spraying, space spraying, and insecticide treated material reduce the number of vectors

What this paper adds

Pyrethroid impregnated curtains can considerably reduce the incidence rate of cutaneous leishmaniasis in areas where indoor transmission is predominant  相似文献   

10.
Sandflies (Diptera: Psychodidae) (Newstead, 1911) are blood‐feeding insects that transmit human pathogens including Leishmania (Trypanosomatida: Trypanosomatidae) parasites, causative agents of the leishmaniases. To elucidate Leishmania transmission cycles, conclusive identification of vector species is essential. Molecular approaches including matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) protein profiling have recently emerged to complement morphological identification. The aim of this study was to evaluate the effect of the trap type used to collect sandflies, specifically Centers for Disease Control (CDC) light or sticky traps, the two most commonly used in sandfly surveys, on subsequent MALDI‐TOF MS protein profiling. Specimens of five species (Phlebotomus ariasi, Phlebotomus papatasi, Phlebotomus perniciosus, Phlebotomus sergenti, Sergentomyia minuta) collected in periurban and agricultural habitats in southeast Spain were subjected to protein profiling. Acquired protein spectra were queried against an in‐house reference database and their quality assessed to evaluate the trap type effect. The results indicate that trap choice can substantially affect the quality of protein spectra in collected sandflies. Whereas specimens retrieved from light traps produced intense and reproducible spectra that allowed reliable species determination, profiles of specimens from sticky traps were compromised and often did not enable correct identification. Sticky traps should therefore not be used in surveys that deploy MALDI‐TOF MS protein profiling for species identification.  相似文献   

11.
Monitoring phlebotomine sandflies in urban areas is key for epidemiological studies in susceptible populations. This paper describes sandfly fauna that were present in an urban area of the municipality of Tapachula, Chiapas, Mexico, and were captured with Shannon and CDC light traps. During February and March of 2014, 1,442 sandflies were captured, specifically Lutzomyia cruciata (Coquillet) (98.8%), Lutzomyia cayennensis cayennensis (Floch and Abonnenc) (0.8%), Lutzomyia chiapanensis (Dampf) (0.3%) and Lutzomyia atulapai (De León) (0.1%). Lu. cruciata was the most abundant and the most frequently trapped species. This is the first record of its remarkable ability to adapt to urban green areas. The three other species trapped represent new records of geographic distribution for the study region. These results indicate the need to establish measures for reducing both human contact with this vector and the risk of possible sites of infection.  相似文献   

12.
Centers For Disease Control and Prevention (CDC) light traps were modified for use with light-emitting diodes (LED) and compared against a control trap (incandescent light) to determine the effectiveness of blue, green, and red lights against standard incandescent light routinely used for sand fly surveillance. Light traps were baited with dry ice and rotated through a 4 x 4 Latin square design during May, June, and July, 2006. Trapping over 12 trap nights yielded a total of 2,298 sand flies in the village of Bahrif, 6 km north of Aswan on the east bank of the Nile River in southern Egypt. Phlebotomus papatasi comprised 94.4% of trap collections with five other species collected in small numbers. Over half (55.13%) of all sand flies were collected from red light traps and significantly more sand flies (P < 0.05) were collected from red light traps than from blue, green, or incandescent light traps. Red light traps collected more than twice as many sand flies as control (incandescent) traps and > 4 x more than blue and green light traps. Results indicate that LED red light is a more effective substitute for standard incandescent light when surveying in areas where P. papatasi is the predominant sand fly species. Each LED uses approximately 15% of the energy that a standard CDC lamp consumes, extending battery life and effective operating time of traps. Our prototype LED-modified traps performed well in this hot, arid environment with no trap failures.  相似文献   

13.
Phlebotomine sandflies were captured in rural settlement and periurban areas of the municipality of Guaraí in the state of Tocantins (TO), an endemic area of American cutaneous leishmaniasis (ACL). Forty-three phlebotomine species were identified, nine of which have already been recognised as ACL vectors. Eleven species were recorded for the first time in TO. Nyssomyia whitmani was the most abundant species, followed by Evandromyia bourrouli, Nyssomyia antunesi and Psychodopygus complexus. The Shannon-Wiener diversity index and the evenness index were higher in the rural settlement area than in the periurban area. The evaluation of different ecotopes within the rural area showed the highest frequencies of Ev. bourrouli and Ny. antunesi in chicken coops, whereas Ny. whitmani predominated in this ecotope in the periurban area. In the rural settlement area, Ev. bourrouli was the most frequently captured species in automatic light traps and Ps. complexus was the most prevalent in Shannon trap captures. The rural settlement environment exhibited greater phlebotomine biodiversity than the periurban area. Ps. complexus and Psychodopygus ayrozai naturally infected with Leishmania (Viannia) braziliensis were identified. The data identified Ny. whitmani as a potential ACL vector in the periurban area, whereas Ps. complexus was more prevalent in the rural environment associated with settlements.  相似文献   

14.
Cutaneous leishmaniasis (CL) in the state of Rio de Janeiro is sporadic and can be characterised as a peridomestic transmission that occurs in modified natural environments. The aim of this work was to study the fauna and ecological characteristics of sandflies in an environmentally protected area (the State Park of Serra da Tiririca) within the remnants of the Atlantic Forest in the municipalities of Niterói and Maricá and their possible relationship with leishmaniasis. Captures were performed using light traps during the night once a month for one year in both sylvatic environments and areas surrounding homes near the park. A total of 1,037 sandflies were captured, belonging to nine genera and 12 species: Evandromyia tupynambai (34.1%), Migonemyia migonei (20.6%), Brumptomyia cunhai (13.8%), Micropygomyia schreiberi (9.7%), Psathyromyia lanei (6.5%), Brumptomyia nitzulescui (5.7%), Evandromyia edwardsi (5.4%), Nyssomyia intermedia (2.8%), Evandromyia cortelezzii (0.6%), Pintomyia bianchigalatiae (0.5%), Lutzomyia longipalpis (0.2%) and Sciopemyia microps (0.1%). Both Mg. migonei and Ny. intermedia may be acting as vectors of CL in this area.  相似文献   

15.
Recently, light traps equipped with light-emitting diode (LED) lights have been used to monitor and control nocturnal insect pests. The oriental armyworm, Mythimna separata Walker, is an important cosmopolitan agriculture pest. The phototactic responses of nocturnal insects, including moths are influenced by abiotic and biological factors. The present study aimed to evaluate the phototactic response to different wavelength LED lights to determine the wavelength to which M. separata adults are most sensitive, and then identify the effects of several factors on the phototactic response. Our experiments revealed that M. separata adult moths had a significantly higher attraction rate to the green (520?nm) LED light compared with other LED lights, the green LED light was 1.28 times more attractive the moths than the commercial double-wave light used as a control. The phototactic response of the adult moths was significantly influenced by several factors, including adaption time in darkness, age, mating status and sexuality. These findings suggest that using a green LED light as a light source in trap could be effective in monitoring or controlling M. separata moths. Our results may provide a theoretical and scientific basis for improving the light trap technique for M. separata moths.  相似文献   

16.
Visceral leishmaniasis (VL) is a disease that results in approximately 50 000 human deaths annually. It is transmitted through the bites of phlebotomine sandflies and around two‐thirds of cases occur on the Indian subcontinent. Indoor residual spraying (IRS), the efficacy of which depends upon sandfly adults resting indoors, is the only sandfly control method used in India. Recently, in Bihar, India, considerable sandfly numbers have been recorded outdoors in village vegetation, which suggests that IRS may control only a portion of the population. The purpose of this study was to revisit previously published results that suggested some sandflies to be arboreal and to rest on outlying plants by using Centers for Disease Control light traps to capture sandflies in vegetation, including banana plants and palmyra palm trees, in two previously sampled VL‐endemic Bihari villages. Over 3500 sandflies were trapped in vegetation over 12 weeks. The results showed the mean number of sandflies collected per trap night were significantly higher in banana trees than in other vegetation (P = 0.0141) and in female rather than male palmyra palm trees (P = 0.0002). The results raise questions regarding sandfly dispersal, oviposition and feeding behaviours, and suggest a need to refine current control practices in India and to take into account an evolving understanding of sandfly ecology.  相似文献   

17.
The habitat associations of the noctuid moth Double Line Mythimna turca (Linnaeus 1761) were studied in three areas in Britain by setting up light traps equidistant along transects which passed through different habitat types. Counts were made of M. turca at each trap station and the results compared with the habitat present in the vicinity of each trap. The results using chi-square analysis indicate that the preferred habitats for M. turca are woodland and Pteridium aquilinum scrub, especially where the grasses Agrostis capillaris and Holcus mollis occur. The environmental factors affecting moth catches are discussed and chi-squared expectations are adjusted to take account of the different efficiency of light traps in open grassland and woodland situations. The light trap transect method is shown to be useful for moth species where little is known of their ecology and can be used to provide a straightforward insight informing additional targeted autecological studies. The methodology may be less suited to those species which occur at low density, are poorly attracted to light or are known to migrate.  相似文献   

18.
The melon thrips, Thrips palmi Karny (Thysanoptera: Thripidae), is a serious agricultural pest of many crops. Previous studies have shown that red light decreases the number of Thrips palmi in greenhouses. In order to understand how red light affects T. palmi, we examined the behavioral responses to host plants that were irradiated with a red light-emitting diode panel (660 nm) in an environment with natural or fluorescent (normal-white) light. When T. palmi were allowed to move freely around in the experimental arena, we found that fewer individuals were attracted to plants irradiated by red light than to plants under normal light illumination. We then used a sticky trap of green coloration to exclude olfactory and visual stimuli associated with the host plants in order to test binary choice behavior in T. palmi. The number of thrips attracted to the green sticky trap irradiated with red light was approximately half of that without red light irradiation. This is the first study to show that an addition of red light can change the behavior of insects, leading to an avoidance of green targets in an environment of normal illumination.  相似文献   

19.
The aims of the study were to (a) investigate the effect of trapping methods on alpha diversity; and (b) enhance the knowledge of the sandfly assemblage in the state of Quintana Roo. Field work was undertaken in a tropical forest of southern Mexico from August 2013 to July 2014. Sampling was conducted monthly during three consecutive nights. For each trapping night, 12 different types of trap were operated from 18.00 to 24.00 hours in four transects. Measures of alpha community diversity were based on the quantification of the number of species (Chao 2, Jackknife 2, Clench's equation, Margalef's index) and the community structure, as well as the dominance (Simpson and Berger‐Parker indexes) and evenness (Shannon's entropy index, true diversity of the Jost and Pielou index). With a total sampling effort of 1728 night‐traps, 16 101 phlebotomine sandflies were collected; they represented two genera and 13 species. Diversity estimates of 100% (Chao 2 and Clench's equation) and 85% (Jackknife 2) of potential species in the study area were calculated. Shannon traps and CDC light traps indicated the largest number of species, but only Shannon traps showed the greatest abundance. This inventory of sandflies is an important activity to enhance our knowledge of sandfly assemblages and guilds. The ultimate goal of studying alpha diversity in sandflies would be to have a better understanding of the population dynamics and all complex networks of interactions that may, in turn, be associated with the epidemiology of the disease.  相似文献   

20.
An analysis of the dietary content of haematophagous insects can provide important information about the transmission networks of certain zoonoses. The present study evaluated the potential of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mitochondrial cytochrome B (cytb) gene to differentiate between vertebrate species that were identified as possible sources of sandfly meals. The complete cytb gene sequences of 11 vertebrate species available in the National Center for Biotechnology Information database were digested with Aci I, Alu I, Hae III and Rsa I restriction enzymes in silico using Restriction Mapper software. The cytb gene fragment (358 bp) was amplified from tissue samples of vertebrate species and the dietary contents of sandflies and digested with restriction enzymes. Vertebrate species presented a restriction fragment profile that differed from that of other species, with the exception of Canis familiaris and Cerdocyon thous. The 358 bp fragment was identified in 76 sandflies. Of these, 10 were evaluated using the restriction enzymes and the food sources were predicted for four: Homo sapiens (1), Bos taurus (1) and Equus caballus (2). Thus, the PCR-RFLP technique could be a potential method for identifying the food sources of arthropods. However, some points must be clarified regarding the applicability of the method, such as the extent of DNA degradation through intestinal digestion, the potential for multiple sources of blood meals and the need for greater knowledge regarding intraspecific variations in mtDNA.  相似文献   

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