Biogeographical aspects of the occurrence of Nyssomyia neivai and Nyssomyia intermedia (Diptera: Psychodidae) in a sympatric area of the Brazilian savannah

Nyssomyia intermedia and Nyssomyia neivai constitute a species complex associated with Leishmania transmission. The aim of this study was to analyse the ecological profiles of the Ny. intermedia and Ny. neivai populations in a sympatric area in the Brazilian savannah along the banks of the Velhas River. Captures were performed from July 2003-June 2005 in two distinct environments: a gallery forest with various degrees of anthropogenic modification and animal shelters. A total of 20,508 Ny. neivai (86%) and Ny. intermedia (14%) sandflies were collected. The difference between the proportions of the sandflies that were collected (Ny. neivai/Ny. intermedia) per bank was significant. The right bank presented a greater number of sandflies (65%) and more preserved vegetation. The abundance of Ny. neivai was higher than that of Ny. intermedia on both banks. The results demonstrate that anthropic activities can affect the sandfly populations in this area, thereby leading to a reduction in species abundance. Nevertheless, the environments with higher levels of antropogenic modification displayed sandfly population numbers that favour the Leishmania transmission cycle.

Species diversity of sandflies (Diptera: Psychodidae) during different seasons and in different environments in the district of Taquaruçú, state of Tocantins, Brazil

Phlebotomine sandflies are the vectors for the protozoan parasites that cause leishmaniasis. The present study investigated the species composition of sandfly fauna in the rural district of Taquaruçú, municipality of Palmas, state of Tocantins, Brazil and compared the diversity of species among intradomicile, peridomicile and forest environments during the dry and rainy seasons. Sandflies were collected using CDC light traps over the course of three months during the dry and rainy seasons. A total of 767 specimens were captured, belonging to different 32 species. The most abundant species were Micropygomyia goiana (Martins, Falcão & Silva), Sciopemyia sordellii (Shannon & Del Ponte), Evandromyia carmelinoi (Ryan Fraiha, Lainson & Shaw), Evandromyia termitophila (Martins, Falcão & Silva), Nyssomyia whitmani (Antunes & Coutinho) and Lutzomyia longipalpis (Lutz & Neiva). The highest species diversity (30) and the greatest percentage of specimens (78.3%) were obtained during the rainy season. During the dry season, the species richness and abundance were greater in domestic environments. However, during the rainy season, the forest displayed the highest species richness and the domestic environment exhibited the greatest species abundance. Several important vector species are reported in this study.

Lutzomyia diamantinensis sp. nov., a new phlebotomine species (Diptera: Psychodidae) from a quartzite cave in Diamantina, state of Minas Gerais, Brazil

A new species of Brazilian phlebotomine sandfly found in Brazil, municipality of Diamantina, state of Minas Gerais, is described based on males and females collected in a quartzite cave. The body of spermathecae is continuous to the individual duct, lanky and tapering at the end, with conical shaped, not striated and presenting the head with dense setae. The male presents gonostyle with four spines and a small subterminal seta and gonocoxite with one group of persistent setae. The paramere is simple with a group of small setae on the dorsal apex. The morphological features of this new species permit its inclusion in the migonei group.

Sandflies (Diptera: Psychodidae) from caves of the quartzite Espinhaço Range, Minas Gerais, Brazil

This study investigated the sandfly fauna of two quartzite caves in the Espinhaço Mountain Range, located in the municipality of Diamantina, state Minas Gerais. From August 2010-July 2011, entomological sampling was performed in the caves of Salitre and Monte Cristo with two HP light traps exposed in the photic and aphotic zones of each cave. The sandfly fauna consisted of 17 species, among which Lutzomyia cipoensis was predominant (54.76%). The male/female ratio in the total captures was 1:2.5. The aphotic zone showed the highest frequency of specimens captured (65%). A greater density of sandflies occurred during the summer (January-February), coinciding with the period of higher temperatures, humidity and rainfall. The presence of Lutzomyia longipalpis, Lutzomyia whitmani and Lutzomyia pessoai, proven or suspected vectors of leishmaniasis, is of concern because the area is visited by many tourists.

Appraisal of Phlebotomus argentipes habitat suitability using a remotely sensed index in the kala-azar endemic focus of Bihar, India

Visceral leishmaniasis, or kala-azar, is recognised as a serious emerging public health problem in India. In this study, environmental parameters, such as land surface temperature (LST) and renormalised difference vegetation indices (RDVI), were used to delineate the association between environmental variables and Phlebotomus argentipes abundance in a representative endemic region of Bihar, India. The adult P. argentipes were collected between September 2009-February 2010 using the hand-held aspirator technique. The distribution of P. argentipes was analysed with the LST and RDVI of the peak and lean seasons. The association between environmental covariates and P. argentipes density was analysed a multivariate linear regression model. The sandfly density at its maximum in September, whereas the minimum density was recorded in January. The regression model indicated that the season, minimum LST, mean LST and mean RDVI were the best environmental covariates for the P. argentipes distribution. The final model indicated that nearly 74% of the variance of sandfly density could be explained by these environmental covariates. This approach might be useful for mapping and predicting the distribution of P. argentipes, which may help the health agencies that are involved in the kala-azar control programme focus on high-risk areas.

Phlebotomine sandflies (Diptera: Psychodidae) from Lábrea, state of Amazonas, Brazil, with a description of Evandromyia (Aldamyia) apurinan Shimabukuro, Figueira & Silva, sp. nov.

An entomological survey was conducted from July-December 2009 and September-December 2010, as part of the epidemiological monitoring of American cutaneous leishmaniasis (ACL) in the municipality of Lábrea, state of Amazonas (AM), Brazil. Sandflies were collected using CDC light traps installed in intra and peridomiciliary locations, as well as the border of forested areas around houses where autochthonous cases of ACL were recorded. A total of 510 sandflies belonging to 26 species were collected. The most abundant species was Nyssomyia antunesi (44.5%) followed by Evandromyia walkeri (10.6%) and Micropygomyia rorotaensis (9.8%). Here we also describe Evandromyia (Aldamyia) apurinan sp. nov. and report new records for Trichophoromyia flochi and Evandromyia sipani in AM and Brazil, respectively. Our results describe the composition of the sandfly fauna in the south of AM and suggest Ny. antunesi as the putative vector in the transmission of Leishmania in this area of the Amazon Region.

Sandflies (Diptera: Psychodidae) in rural and urban environments in an endemic area of cutaneous leishmaniasis in southern Brazil

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.

Detection of Wolbachia pipientis, including a new strain containing the wsp gene, in two sister species of Paraphlebotomus sandflies, potential vectors of zoonotic cutaneous leishmaniasis

Individual, naturally occurring Phlebotomus mongolensis and Phlebotomus caucasicus from Iran were screened for infections with the maternally inherited intracellular Rickettsia-like bacterium Wolbachia pipientis via targeting a major surface protein gene (wsp). The main objective of this study was to determine if W. pipientis could be detected in these species. The sandflies were screened using polymerase chain reaction to amplify a fragment of the Wolbachia surface protein gene. The obtained sequences were edited and aligned with database sequences to identify W. pipientis haplotypes. Two strains of Wolbachia were found. Strain Turk 54 (accession EU780683) is widespread and has previously been reported in Phlebotomus papatasi and other insects. Strain Turk 07 (accession KC576916) is a novel strain, found for first time in the two sister species. A-group strains of W. pipientis occur throughout much of the habitat of these sandflies. It is possible that Wolbachia is transferred via horizontal transmission. Horizontal transfer could shed light on sandfly control because Wolbachia is believed to drive a deleterious gene into sandflies that reduces their natural population density. With regard to our findings in this study, we can conclude that one species of sandfly can be infected with different Wolbachia strains and that different species of sandflies can be infected with a common strain.

Leishmania infection and host-blood feeding preferences of phlebotomine sandflies and canine leishmaniasis in an endemic European area, the Algarve Region in Portugal

The Algarve Region (AR) in southern Portugal, which is an international tourist destination, has been considered an endemic region of zoonotic leishmaniasis caused by Leishmania infantum since the 1980s. In the present study, phlebotomine and canine surveys were conducted to identify sandfly blood meal sources and to update the occurrence of Leishmania infection in vectors and dogs. Four sandfly species were captured: Phlebotomus perniciosus, Phlebotomus ariasi, Phlebotomus sergenti and Sergentomyia minuta. In one P. perniciosus female, L. infantum DNA was detected. Blood meal tests showed that this species had no host preferences and was an opportunistic feeder. An overall canine leishmaniasis (CanL) seroprevalence of 16.06% was found; the seroprevalence was 3.88% in dogs housed in kennels and 40.63% in dogs that attended veterinary clinics. The simultaneous occurrence of dogs and P. perniciosus infected with L. infantum in the AR indicates that the region continues to be an endemic area for CanL. Our results reinforce the need for the systematic spatial distribution of phlebotomine populations and their Leishmania infection rates and the need to simultaneously perform pathogen monitoring in both invertebrate and vertebrate hosts to investigate the transmission, distribution and spreading of Leishmania infection.

Kazal-type serine proteinase inhibitors in the midgut of Phlebotomus papatasi

Sandflies (Diptera: Psychodidae) are important disease vectors of parasites of the genus Leishmania, as well as bacteria and viruses. Following studies of the midgut transcriptome of Phlebotomus papatasi, the principal vector of Leishmania major, two non-classical Kazal-type serine proteinase inhibitors were identified (PpKzl1 and PpKzl2). Analyses of expression profiles indicated that PpKzl1 and PpKzl2 transcripts are both regulated by blood-feeding in the midgut of P. papatasi and are also expressed in males, larva and pupa. We expressed a recombinant PpKzl2 in a mammalian expression system (CHO-S free style cells) that was applied to in vitro studies to assess serine proteinase inhibition. Recombinant PpKzl2 inhibited α-chymotrypsin to 9.4% residual activity and also inhibited α-thrombin and trypsin to 33.5% and 63.9% residual activity, suggesting that native PpKzl2 is an active serine proteinase inhibitor and likely involved in regulating digestive enzymes in the midgut. Early stages of Leishmania are susceptible to killing by digestive proteinases in the sandfly midgut. Thus, characterising serine proteinase inhibitors may provide new targets and strategies to prevent transmission of Leishmania.

Phlebotomus (Legeromyia) multihamatus subg. nov., sp. nov. from Gabon (Diptera: Psychodidae)

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.

Oviposition behaviour of Phlebotomus argentipes - A laboratory-based study

The breeding habitat of sandflies is a little studied and poorly understood phenomenon. More importantly, oviposition behaviour is a largely neglected aspect of sandfly biology and this knowledge gap further undermines our understanding of the biology of sandflies. Pheromones released by the eggs play an important role in identifying good sites for oviposition by female insects. Several recent studies have examined the oviposition pheromone. The present study provides a preliminary report on the oviposition behaviour of Phlebotomus argentipes, the only vector of kala-azar (or visceral leishmaniasis) on the Indian sub-continent. Sandflies prefer to oviposit their eggs on surfaces that contain organic substances, especially substances with an odour of decaying animal products and the remains of conspecific eggs. The results presented here suggest that the odour released by the organic substances of old sandfly colony remains that contain dead flies, old unhatched eggs, larval food containing vertebrate faeces, frass and other organic matter serves as an attractant for the ovipositing females of P. argentipes and hence greatly increases the number of oviposited eggs compared to eggs deposited in controlled oviposition pots. This result will be helpful in maintaining an efficient colony of P. argentipes and may be a promising tool for monitoring and controlling the target insect as part of a synergistic approach.

A new species of phlebotomine, Trichophoromyia adelsonsouzai (Diptera: Psychodidae) of Brazilian Amazonia

The phlebotomine sandfly Trichophoromyia adelsonsouzai sp. nov. is described and illustrated based on the male and female morphological characteristics of specimens collected at Km 27 of the Trans-Amazonian Highway, municipality of Vitória do Xingu, state of Pará, Brazilian Amazonia. This is an area subject to the direct influence of Belo Monte hydroelectric system. With the description of this new species the number of Trichophoromyia sandflies recorded in Brazil is increased to 20.

Characterisation of divergent flavivirus NS3 and NS5 protein sequences detected in Rhipicephalus microplus ticks from Brazil

Transcripts similar to those that encode the nonstructural (NS) proteins NS3 and NS5 from flaviviruses were found in a salivary gland (SG) complementary DNA (cDNA) library from the cattle tick Rhipicephalus microplus.Tick extracts were cultured with cells to enable the isolation of viruses capable of replicating in cultured invertebrate and vertebrate cells. Deep sequencing of the viral RNA isolated from culture supernatants provided the complete coding sequences for the NS3 and NS5 proteins and their molecular characterisation confirmed similarity with the NS3 and NS5 sequences from other flaviviruses. Despite this similarity, phylogenetic analyses revealed that this potentially novel virus may be a highly divergent member of the genus Flavivirus. Interestingly, we detected the divergent NS3 and NS5 sequences in ticks collected from several dairy farms widely distributed throughout three regions of Brazil. This is the first report of flavivirus-like transcripts inR. microplus ticks. This novel virus is a potential arbovirus because it replicated in arthropod and mammalian cells; furthermore, it was detected in a cDNA library from tick SGs and therefore may be present in tick saliva. It is important to determine whether and by what means this potential virus is transmissible and to monitor the virus as a potential emerging tick-borne zoonotic pathogen.

Species composition and seasonal abundance of sandflies (Diptera: Psychodidae: Phlebotominae) in coffee agroecosystems

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 Leishmaniaspp.