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1.
Mem Inst Oswaldo Cruz ; 116: e210230, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34816885

RESUMO

BACKGROUND: Leishmaniases are diseases transmitted by some species of sand flies and are widely distributed throughout the tropical regions of the planet. Despite the low mobility of these vectors, the geographical distributions of some species are quite extensive, which hinders control and surveillance measures in endemic areas. OBJECTIVES: The present study investigated the flying capacity of sand flies. METHODS: Four Hoover Penido (HP)-type light traps were positioned in the centre of the Velhas' River, about 80 metres equidistant from each other. We also realised capture/release/recapture attempts to assess possible capacity of phlebotomine fly uninterrupted up to 150 metres. Captured sand flies from one side of the river were marked using fluorescent powder (Luminous Paint kit, Bioquip®) and released on the other side, approximately 150 m distant. Recapture attempts were made on river's bank up to 30 days post-release. FINDINGS: Six sand flies of the species Nyssomyia neivai (n = 4), Ny. intermedia (n = 1) and Evandromyia lenti (n = 1) were captured in the centre of the river. There were no recaptures of the 1,450 marked-and-released sand flies. MAIN CONCLUSIONS: The results obtained disagree with data found in the literature regarding the flight capacity of sand fly vectors of leishmaniasis.


Assuntos
Leishmaniose , Phlebotomus , Psychodidae , Animais , Insetos Vetores
2.
East Mediterr Health J ; 27(9): 911-917, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34569047

RESUMO

Background: Sandflies are active vectors of several diseases, including leishmaniasis, which Morocco hopes to eliminate by 2030. Despite efforts to limit their spread, they still remain a public health problem in the country, as the behaviour of individuals in relation to sandflies plays an important role in the sustainability of the epidemiological cycle. Aims: To explore and determine the knowledge and behaviours related to sandfly diseases. Methods: A quantitative method was adopted using a questionnaire assisted by a personal interview. Based on the epidemiological situation of leishmaniasis cases reported in recent years in Al-Hajeb province, we conducted a field survey among 281 persons in April and May 2019 residing in the communities where the cases of the disease are registered. Results: 61.6% of Moroccans know sandflies by the name "Chniwla"; 44.1% thought that sandflies do not transmit diseases; 41.3% thought they multiplied in contaminated water; 52.7% thought sandfly bites could not be avoided; and 6.4% recognized the role of individuals in the fight against vectors. Conclusions: The need to raise public awareness of the risks of sandflies, using the popular concepts obtained to simplify scientific terms and formulate targeted health education strategies that make the individual an active player in vector control.


Assuntos
Leishmaniose , Phlebotomus , Psychodidae , Animais , Humanos , Insetos Vetores , Leishmaniose/epidemiologia , Leishmaniose/prevenção & controle , Marrocos/epidemiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-34501863

RESUMO

Zoonotic cutaneous leishmaniasis (ZCL), endemic in Central and Southern Tunisia, is caused by Leishmania major (Kinetoplastida: Trypanosomatidae), which is transmitted by the sand fly Phlebotomus papatasi. In Tunisia, the fat sand rat Psammomys obesus and the desert jird Meriones shawi are the principal reservoir hosts of L. major. The presence of the P. papatasi vector of the L. major etiologic agent of ZCL was assessed in the vicinity of villages in endemic areas of Central Tunisia. The study was performed from September through October 2019, a period corresponding to the main peak of activity of P. papatasi. Sand flies were collected from rodent burrows located at the ecotone level, which is the transition zone between the natural environment and human settlement. Sand flies were identified to species level and tested for the presence of L. major by PCR. Our entomological survey showed that P. papatasi is the most abundant sand fly species associated with rodent burrows, and this abundance is even higher in ecotones primarily occupied by P. obesus in comparison to ecotones occupied by M. shawi. Infections with Leishmania major were detected only in P. papatasi, with an overall minimum infection rate (MIR) of 2.64%. No significant difference was observed between the MIRs in ecotones of P. obesus and of M. shawi. Incidence of ZCL in the studied areas ranged from 200 to 700 cases per 100,000 inhabitants, with a mean incidence of 385.41 per 100,000. Higher ZCL incidence was identified in ecotones of M. shawi compared to ecotones of P. obesus. ZCL cases are positively correlated with the MIRs. Considering the short flight range of P. papatasi, increases in its densities associated with burrows of P. obesus or M. shawi at the ecotone level expand the overlap of infected vectors with communities and subsequently increase ZCL incidence. Therefore, control measures should target P. papatasi populations at the ecotones.


Assuntos
Leishmania major , Leishmaniose Cutânea , Phlebotomus , Animais , Leishmaniose Cutânea/epidemiologia , Medição de Risco , Tunísia/epidemiologia
4.
Acta Trop ; 224: 106150, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34562421

RESUMO

Cutaneous Leishmaniasis (CL) is a disease caused by Leishmania species and transmitted by the bites of infected female sand fly species. The diversity of these insects in Rondônia State (where CL is the predominant form) is large but unexplored, and consequently the vector species are unknown. The purpose of this study was to evaluate the sand fly fauna in two environments (forest fragment and peridomicile) in rural areas of four municipalities of the state, DNA amplification of Leishmania species and the presence of blood meal sources for these insects. After identifying the species, sample coverage was applied to estimate the fauna coverage in each environment. Females were used to amplify and detect Leishmania DNA and blood meal sources, then posteriorly identified by sequencing. A total of 1706 individuals were included in 61 species, which was a sample coverage of 97% for the forest fragments (56 species), whereas 98% was observed (32 species) in peridomiciles. Next, 41 pools were prepared from 1227 females, and none were positive for Leishmania DNA. We observed 160 engorged females (forest fragments: 21, peridomiciles: 139) belonging to females of the Antunesi complex and another eight species. Two of these females were positive for Leishmania braziliensis-DNA: one in the Antunesi complex and one in Psychodopygus hirsutus. Seven blood meal sources were identified by sequencing analysis: Bos taurus and Sus scrofa from the peridomiciles, and Dasypus novemcinctus, Pecari tajacu, Philander canus, Plecturocebus bernhardi, and Tamandua tetradactyla from the forest fragments. Our data confirmed the feeding behavior of field-caught sand flies and could contribute to our understanding about local vectors and possible reservoirs in the transmission of Leishmania spp.


Assuntos
Leishmania , Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Bovinos , Feminino , Humanos , Insetos Vetores , Leishmania/genética
5.
PLoS One ; 16(9): e0256819, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34529694

RESUMO

Phlebotomus argentipes is the vector of Leishmania donovani which causes the disease leishmaniasis, a neglected tropical disease and a growing health problem in Sri Lanka. A proper understanding of the population genetic structure of sand fly vectors is considered important prior to planning and implementation of a successful vector control program. Thus, the present study was conducted to determine the population genetic structure of sand fly vectors in Sri Lanka. Two mitochondrial genes namely Cytochrome c oxidase subunit 1 (Cox 1) and Cytochrome b (Cytb), and the internal transcribed spacer 2 (ITS2) region from the nuclear ribosomal DNA were used for molecular characterization. Analyses included maximum likelihood method, network analysis and DNA polymorphisms. The outcome revealed unique sequences of all genomic regions studied except the cox 1 gene had a relationship with sand flies isolated previously from Sri Lanka, India and Israel and cytb gene of 4 sand flies that aligned with those isolated earlier from Sri Lanka and 3 from Madagascar. Furthermore, cox 1 gene and ITS 2 region analyses based on FST values indicated a possible gene flow between the study sites whereas cytb gene analysis favoured the existence of genetically distinct populations of P. argentipes in each of the study sites. Poor population differentiation of P. argentipes, a possible consequence of a gene flow, is indeed of concern due to the risk imposed by promoting the spread of functionally important phenotypes such as insecticide resistance across the country, making future vector control efforts challenging.


Assuntos
DNA Ribossômico , Insetos Vetores/genética , Leishmaniose Visceral/epidemiologia , Phlebotomus/genética , Animais , Variação Genética , Sri Lanka/epidemiologia
6.
Parasitol Res ; 120(9): 3105-3111, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34387751

RESUMO

Visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are diseases transmitted by infected female sand flies. Since the eradication of malaria in Turkey, CL is the main vector-borne disease in the country, with more than 2000 cases per year, making it a significant public health problem. The aims of this study were to carry out an entomological survey in Antalya Province, an endemic area for CL in the Mediterranean Region of Turkey, to identify sand fly fauna and to screen female specimens for the presence of Leishmania parasites (Leishmania infantum, L. tropica, L. major, and L. donovani) using molecular analysis. Sand flies were collected in 42 localities of seven districts in Antalya Province using CDC miniature light traps in two different periods, June 2012 and September 2013. The specimens were kept in 96% ethanol until the dissection was done. The head and genitalia of the specimens were cut for preparing individual slides for species identification. The rest of the body of female specimens was kept separately. The specimens were identified at the species level, and 27 pools were generated according to the locations and species for screening the presence of Leishmania. A commercial kit was used for DNA extractions. Real-time and conventional polymerase chain reaction (PCR) targeting the internal transcribed spacer region (ITS1) were then performed. In total, 1306 specimens comprising nine species belonging to the Phlebotomus genus were collected in the study region, with Phlebotomus neglectus/syriacus (38.82%) the most abundant, followed by P. alexandri (21.67%) and P. tobbi (20.44%). In the 27 pools, Leishmania infantum DNA was detected in four pools containing P. neglectus/syriacus and one pool containing P. tobbi. In conclusion, the sand fly fauna in the Antalya Province is diverse. The probable vector sand fly species are P. neglectus/syriacus and P. tobbi with high dominance (59.26%), which indicates a high risk of CL transmission. The data presented here may help to shed more light on the transmission cycles of the Leishmania parasite in this CL endemic area.


Assuntos
Leishmania infantum , Phlebotomus , Psychodidae , Animais , Feminino , Insetos Vetores , Turquia/epidemiologia
7.
Parasitol Res ; 120(9): 3091-3103, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34405280

RESUMO

Green periurban residential areas in Mediterranean countries have flourished in the last decades and become foci for leishmaniasis. To remedy the absence of information on vector ecology in these environments, we examined phlebotomine sand fly distribution in 29 sites in Murcia City over a 3-year period, including the plots of 20 detached houses and nine non-urbanized sites nearby. We collected 5,066 specimens from five species using "sticky" interception and light attraction traps. The relative frequency of the main Leishmania infantum vector Phlebotomus perniciosus in these traps was 32% and 63%, respectively. Sand fly density was widely variable spatially and temporally and greatest in non-urbanized sites, particularly in caves and abandoned buildings close to domestic animal holdings. Phlebotomus perniciosus density in house plots was positively correlated with those in non-urbanized sites, greatest in larger properties with extensive vegetation and non-permanently lived, but not associated to dog presence or a history of canine leishmaniasis. Within house plots, sand fly density was highest in traps closest to walls. Furthermore, the study provides a guideline for insect density assessment and reporting and is envisioned as a building block towards the development of a pan-European database for robust investigation of environmental determinants of sand fly distribution.


Assuntos
Leishmania infantum , Leishmaniose , Phlebotomus , Psychodidae , Animais , Cães , Feminino , Insetos Vetores , Leishmaniose/epidemiologia , Leishmaniose/veterinária , Masculino , Espanha
8.
PLoS Negl Trop Dis ; 15(8): e0009101, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34370731

RESUMO

BACKGROUND: In 2005, Bangladesh, India and Nepal agreed to eliminate visceral leishmaniasis (VL) as a public health problem. The approach to this was through improved case detection and treatment, and controlling transmission by the sand fly vector Phlebotomus argentipes, with indoor residual spraying (IRS) of insecticide. Initially, India applied DDT with stirrup pumps for IRS, however, this did not reduce transmission. After 2015 onwards, the pyrethroid alpha-cypermethrin was applied with compression pumps, and entomological surveillance was initiated in 2016. METHODS: Eight sentinel sites were established in the Indian states of Bihar, Jharkhand and West Bengal. IRS coverage was monitored by household survey, quality of insecticide application was measured by HPLC, presence and abundance of the VL vector was monitored by CDC light traps, insecticide resistance was measured with WHO diagnostic assays and case incidence was determined from the VL case register KAMIS. RESULTS: Complete treatment of houses with IRS increased across all sites from 57% in 2016 to 70% of houses in 2019, rising to >80% if partial house IRS coverage is included (except West Bengal). The quality of insecticide application has improved compared to previous studies, average doses of insecticide on filters papers ranged from 1.52 times the target dose of 25mg/m2 alpha-cypermethrin in 2019 to 1.67 times in 2018. Resistance to DDT has continued to increase, but the vector was not resistant to carbamates, organophosphates or pyrethroids. The annual and seasonal abundance of P. argentipes declined between 2016 to 2019 with an overall infection rate of 0.03%. This was associated with a decline in VL incidence for the blocks represented by the sentinel sites from 1.16 per 10,000 population in 2016 to 0.51 per 10,000 in 2019. CONCLUSION: Through effective case detection and management reducing the infection reservoirs for P. argentipes in the human population combined with IRS keeping P. argentipes abundance and infectivity low has reduced VL transmission. This combination of effective case management and vector control has now brought India within reach of the VL elimination targets.


Assuntos
Controle de Insetos/normas , Insetos Vetores/parasitologia , Inseticidas/administração & dosagem , Leishmaniose Visceral/prevenção & controle , Phlebotomus/parasitologia , Animais , Bioensaio , Feminino , Humanos , Índia/epidemiologia , Controle de Insetos/métodos , Resistência a Inseticidas , Leishmaniose Visceral/epidemiologia , Psychodidae/efeitos dos fármacos , Piretrinas/administração & dosagem
9.
Acta Trop ; 222: 106036, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34224717

RESUMO

There is limited information regarding the role of wild mammals in the transmission dynamics of Leishmania infantum. A potential human leishmaniasis hot spot was detected in southern Spain that could not be explained solely by canine leishmaniasis prevalence. The aim of this work was to analyse the involvement of wild rabbits as the main factor affecting this Mediterranean hot spot. A survey of wild rabbits, dogs and sand flies was conducted in the human cases environment. A nearby region without clinical leishmaniasis cases was used as reference control. 51 wild rabbits shot by hunters were analysed by molecular techniques. 1100 sand flies were captured and morphologically identified. Blood collected from patients' relatives/ neighbours (n = 9) and dogs (n = 66) was used for molecular analysis and serology. In Mediterranean leishmaniasis hot spots such as Montefrío municipality (average incidence of 16.8 human cases per 100,000 inhabitants/year), wild rabbits (n = 40) support high L. infantum infection rates (100%) and heavy parasite burdens (average value: 503 parasites/mg) in apparently normal ear skin directly accessible to sand flies, enabling the existence of heavily parasitized Phlebotomus perniciosus females (12.5% prevalence). The prevalence of infection and median parasite load were very low among rabbits captured in Huéscar (n = 11), a human clinical leishmaniasis-free area for the last 18 years. P. perniciosus was the most abundant Phlebotomus species in all the domestic/peridomestic microhabitats sampled, both indoors and outdoors. Accordingly, leishmaniasis is clustering in space and time at this local scale represented by Montefrío due to the proximity of two competent host reservoirs (dogs and heavily parasitized wild rabbits) associated with overlapping sylvatic and domestic transmission cycles through the main vector, P. perniciosus. We highlight the usefulness of determining the prevalence of infection and parasite burden in wild rabbits as a control leishmaniasis measure with the advantage that the use of the ear offers.


Assuntos
Reservatórios de Doenças/parasitologia , Leishmaniose Visceral , Phlebotomus , Coelhos/parasitologia , Animais , Cães , Feminino , Humanos , Leishmania infantum , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Phlebotomus/parasitologia , Espanha/epidemiologia
10.
Parasit Vectors ; 14(1): 371, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34289883

RESUMO

BACKGROUND: Phlebotomine sand flies (Diptera: Psychodiae) in the Republic of Moldova have been understudied for decades. Our study provides a first update on their occurrence, species composition and bloodmeal sources after 50 years. METHODS: During 5 seasons (2013-2017), 58 localities from 20 regions were surveyed for presence of sand flies using CDC light traps and manual aspirators. Species identification was done by a combination of morphological and molecular approaches (DNA barcoding, MALDI-TOF MS protein profiling). In engorged females, host blood was identified by three molecular techniques (RFLP, cytb sequencing and MALDI-TOF peptide mass mapping). Population structure of most abundant species was studied by cox1 haplotyping; phylogenetic analyses of ITS2 and cox1 genetic markers were used to resolve relationships of other detected species. RESULTS: In total, 793 sand flies were collected at 30 (51.7%) localities from 12 regions of Moldova. Three species were identified by an integrative morphological and molecular approach: Phlebotomus papatasi, P. perfiliewi and Phlebotomus sp. (Adlerius), the first being the most abundant and widespread, markedly anthropophilic based on bloodmeal analyses, occurring also indoors and showing low population structure with only five haplotypes of cox1 detected. Distinct morphological and molecular characters of Phlebotomus sp. (Adlerius) specimens suggest the presence of a yet undescribed species. CONCLUSIONS: Our study revealed the presence of stable sand fly populations of three species in Moldova that represent a biting nuisance as well as a potential threat of pathogen transmission and shall be further studied.


Assuntos
Insetos Vetores/classificação , Leishmaniose/transmissão , Psychodidae/classificação , Animais , Feminino , Haplótipos , Especificidade de Hospedeiro , Humanos , Insetos Vetores/genética , Insetos Vetores/parasitologia , Masculino , Moldávia/epidemiologia , Phlebotomus/classificação , Phlebotomus/genética , Phlebotomus/fisiologia , Filogenia , Psychodidae/genética , Psychodidae/fisiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
PLoS Negl Trop Dis ; 15(7): e0009647, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34314425

RESUMO

BACKGROUND: The sand fly Phlebotomus perniciosus is the main vector of Leishmania infantum, etiological agent of zoonotic visceral leishmaniasis in the Western Mediterranean basin. Dogs are the main reservoir host of this disease. The main objective of this study was to determine, under both laboratory and field conditions, if dogs infected with L. infantum, were more attractive to female P. perniciosus than uninfected dogs. METHODOLOGY/PRINCIPAL FINDINGS: We carried out a series of host choice experiments and found that infected dogs were significantly more attractive to P. perniciosus than uninfected dogs in the laboratory as well as in the field. Significantly more P. perniciosus fed on infected dogs than on uninfected dogs. However, the fecundity of P. perniciosus fed on infected dogs was adversely impacted compared to uninfected dogs by lowering the number of laid eggs. Phlebotomus perfiliewi, the second most abundant sand fly species in the field site and a competent vector of L. infantum had similar trends of attractivity as P. perniciosus toward infected dogs under field conditions. CONCLUSIONS: The results strongly suggest that L. infantum causes physiological changes in the reservoir host which lead to the host becoming more attractive to both male and female P. perniciosus. These changes are likely to improve the chance of successful transmission because of increased contact with infected hosts and therefore, infected dogs should be particularly targeted in the control of zoonotic visceral leishmaniasis in North Africa.


Assuntos
Doenças do Cão/parasitologia , Comportamento Alimentar/fisiologia , Leishmania infantum , Leishmaniose Visceral/veterinária , Phlebotomus/fisiologia , Animais , Doenças do Cão/transmissão , Cães , Feminino , Insetos Vetores , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/transmissão , Masculino , Zoonoses
12.
PLoS Negl Trop Dis ; 15(7): e0009517, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34260585

RESUMO

BACKGROUND: In Peru, the information regarding sand fly vectors of leishmaniasis and bartonellosis in the Amazon region is limited. In this study, we carried out sand fly collections in Peruvian lowland and highland jungle areas using different trap type configurations and screened them for Leishmania and Bartonella DNA. METHODOLOGY/PRINCIPAL FINDINGS: Phlebotomine sand flies were collected in Peruvian Amazon jungle and inter Andean regions using CDC light trap, UV and color LED traps, Mosquito Magnet trap, BG Sentinel trap, and a Shannon trap placed outside the houses. Leishmania spp. screening was performed by kDNA PCR and confirmed by a nested cytochrome B gene (cytB) PCR. Bartonella spp. screening was performed by ITS PCR and confirmed by citrate synthase gene (gltA). The PCR amplicons were sequenced to identify Leishmania and Bartonella species. UV and Blue LED traps collected the highest average number of sand flies per hour in low jungle; UV, Mosquito Magnet and Shannon traps in high jungle; and Mosquito Magnet in inter Andean region. Leishmania guyanensis in Lutzomyia carrerai carrerai and L. naiffi in Lu. hirsuta hirsuta were identified based on cytB sequencing. Bartonella spp. related to Bartonella bacilliformis in Lu. whitmani, Lu. nevesi, Lu. hirsuta hirsuta and Lu. sherlocki, and a Bartonella sp. related to Candidatus B. rondoniensis in Lu. nevesi and Lu. maranonensis were identified based on gltA gene sequencing. CONCLUSIONS/SIGNIFICANCE: UV, Blue LED, Mosquito Magnet and Shannon traps were more efficient than the BG-Sentinel, Green, and Red LED traps. This is the first report of L. naiffi and of two genotypes of Bartonella spp. related to B. bacilliformis and Candidatus B. rondoniensis infecting sand fly species from the Amazon region in Peru.


Assuntos
Infecções por Bartonella/transmissão , Bartonella bacilliformis/isolamento & purificação , Controle de Insetos/métodos , Insetos Vetores/fisiologia , Leishmania/isolamento & purificação , Leishmaniose/transmissão , Phlebotomus/fisiologia , Animais , Infecções por Bartonella/microbiologia , Bartonella bacilliformis/classificação , Bartonella bacilliformis/genética , Humanos , Controle de Insetos/instrumentação , Insetos Vetores/microbiologia , Insetos Vetores/parasitologia , Leishmania/classificação , Leishmania/genética , Leishmaniose/parasitologia , Peru , Phlebotomus/microbiologia , Phlebotomus/parasitologia
13.
PLoS Negl Trop Dis ; 15(7): e0009479, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34280193

RESUMO

Phlebotomine sand flies are the main natural vectors of Leishmania, which cause visceral and tegumentary tropical diseases worldwide. However, their taxonomy and evolutionary history remain poorly studied. Indeed, as for many human disease vectors, their small size is a challenge for morphological and molecular works. Here, we successfully amplified unbiased copies of whole genome to sequence thousands of restriction-site associated DNA (RAD) markers from single specimens of phlebotomines. RAD markers were used to infer a fully resolved phylogeny of the subgenus Paraphlebotomus (11 species + 5 outgroups, 32 specimens). The subgenus was not recovered as monophyletic and we describe a new subgenus Artemievus subg. nov. Depaquit for Phlebotomus alexandri. We also confirm the validity of Ph. riouxi which is reinstated as valid species. Our analyses suggest that Paraphlebotomus sensu nov. originated ca 12.9-8.5 Ma and was possibly largely distributed from peri-Mediterranean to Irano-Turanian regions. Its biogeographical history can be summarized into three phases: i) a first split between Ph. riouxi + Ph. chabaudi and other species that may have resulted from the rise of the Saharan belt ca 8.5 Ma; ii) a Messinian vicariant event (7.3-5.3 Ma) during which the prolonged drought could have resulted in the divergence of main lineages; iii) a recent radiation event (3-2 Ma) that correspond to cycles of wet and dry periods in the Middle East and the East African subregions during the Pleistocene. Interestingly these cycles are also hypothetical drivers of the diversification of rodents, in the burrows of which Paraphlebotomus larvae develop. By meeting the challenge of sequencing pangenomics markers from single, minute phlebotomines, this work opens new avenues for improving our understanding of the epidemiology of leishmaniases and possibly other human diseases transmitted by arthropod vectors.


Assuntos
Evolução Molecular , Insetos Vetores/genética , Phlebotomus/genética , Distribuição Animal , Animais , Marcadores Genéticos , Humanos , Insetos Vetores/anatomia & histologia , Insetos Vetores/classificação , Insetos Vetores/fisiologia , Leishmaniose/epidemiologia , Leishmaniose/transmissão , Oriente Médio/epidemiologia , Phlebotomus/anatomia & histologia , Phlebotomus/classificação , Phlebotomus/fisiologia , Filogenia
14.
Acta Trop ; 221: 106005, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34118204

RESUMO

Cutaneous leishmaniasis due to Leishmania tropica represents a major public health problem due to its ability to spread into non-endemic areas by means of its vectors, and the associated dramatic psychosocial impact. The objective of this work was to compare the intra and extradomiciliary density, sex ratio and gonotrophic stage of sand flies from a recent active focus in Morocco. This field study is based on the need to optimize the effectiveness of control programs. Two different capture methods, CDC light traps and sticky traps, were used at two different times of the year, corresponding with the peaks of sand fly abundance. 7,815 sand flies were captured and classified into 13 species belonging to genera Sergentomyia (50.8%) and Phlebotomus (49.2%). Phlebotomus sergenti was the most abundant and frequent species of the genus Phlebotomus both inside (49.3%) and outside houses (52.1%) and it showed the highest density in extradomiciliary captures in June. The proportion of blood-fed females was similar indoors and outdoors (21.5% and 26.3%, respectively). Females in the three gonotrophic stages were found in 26% houses and this was significantly associated with some factors related to housing conditions. Therefore, P. sergenti seems well adapted to both indoors and outdoors biotopes where these females coexist with males. These findings suggest that the adoption of additional measures could benefit the strategy of the Moroccan health authorities, currently consisting of indoor insecticide spraying, given that transmission may also occur outdoors.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Animais , Feminino , Leishmaniose Cutânea/epidemiologia , Masculino , Marrocos , Razão de Masculinidade
15.
PLoS Negl Trop Dis ; 15(6): e0009378, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34081700

RESUMO

BACKGROUND: Sand fly saliva exposure plays an important role in immunity against leishmaniasis where it has mostly been associated with protection. Phlebotomus (Ph.) alexandri transmits Leishmania (L.) infantum, the causative agent of visceral leishmaniasis (VL), in Iraq. Our group recently demonstrated that 20% of Operation Iraqi Freedom (OIF) deployers had asymptomatic VL (AVL) indicative of prior infection by the parasite L. infantum. Little is known about Ph. alexandri saliva, and the human immune response to it has never been investigated. Here, we characterize the humoral and cellular immune response to vector saliva in OIF deployers naturally exposed to bites of Ph. alexandri and characterize their immunological profiles in association to AVL. METHODOLOGY/PRINCIPAL FINDINGS: The humoral response to Ph. alexandri salivary gland homogenate (SGH) showed that 64% of 200 OIF deployers developed an antibody response. To assess the cellular immune response to saliva, we selected a subcohort of subjects based on their post-travel (median 4 months; range 1-22 months) antibody response (SGH Antibody [Ab] positive or negative) as well as their AVL status; ten never-traveled controls were also included. Banked peripheral blood mononuclear cells (PBMC), collected ~10 years after end of deployment, were stimulated with SGH for 96 hours. The levels of IFN- γ, IL-6, IL-10, IL-13 and IL-17 were determined by ELISA. Our findings indicate that OIF deployers mounted a cellular response to SGH where the anti-SGH+ asymptomatic subjects developed the highest cytokine levels. Further, stimulation with SGH produced a mixture of pro-inflammatory and anti-inflammatory cytokines. Contrary to our hypothesis, we observed no correlation between the cellular immune response to Ph. alexandri SGH and prevention from asymptomatic infection with L. infantum. CONCLUSIONS/SIGNIFICANCE: As we found, although all infected deployers demonstrated persistent disease control years after deployment, this did not correlate with anti-saliva systemic cellular response. More exposure to this vector may facilitate transmission of the L. infantum parasite. Since exposure to saliva of Ph. alexandri may alter the human immune response to bites of this vector, this parameter should be taken into consideration when considering the VL risk.


Assuntos
Insetos Vetores/imunologia , Leishmaniose Visceral/transmissão , Phlebotomus/imunologia , Saliva/imunologia , Adulto , Animais , Anticorpos/sangue , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Iraque/epidemiologia , Leishmania infantum/imunologia , Leishmaniose Visceral/epidemiologia , Leucócitos Mononucleares , Masculino , Risco , Células Th2
16.
PLoS Negl Trop Dis ; 15(6): e0009448, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34106920

RESUMO

BACKGROUND: In Mali, cutaneous leishmaniasis (CL) and filariasis are co-endemic. Previous studies in animal models of infection have shown that sand fly saliva enhance infectivity of Leishmania parasites in naïve hosts while saliva-specific adaptive immune responses may protect against cutaneous and visceral leishmaniasis. In contrast, the human immune response to Phlebotomus duboscqi (Pd) saliva, the principal sand fly vector in Mali, was found to be dichotomously polarized with some individuals having a Th1-dominated response and others having a Th2-biased response. We hypothesized that co-infection with filarial parasites may be an underlying factor that modulates the immune response to Pd saliva in endemic regions. METHODOLOGY/PRINCIPAL FINDINGS: To understand which cell types may be responsible for polarizing human responses to sand fly saliva, we investigated the effect of salivary glands (SG) of Pd on human monocytes. To this end, elutriated monocytes were cultured in vitro, alone, or with SG, microfilariae antigen (MF ag) of Brugia malayi, or LPS, a positive control. The mRNA expression of genes involved in inflammatory or regulatory responses was then measured as were cytokines and chemokines associated with these responses. Monocytes of individuals who were not exposed to sand fly bites (mainly North American controls) significantly upregulated the production of IL-6 and CCL4; cytokines that enhance leishmania parasite establishment, in response to SG from Pd or other vector species. This selective inflammatory response was lost in individuals that were exposed to sand fly bites which was not changed by co-infection with filarial parasites. Furthermore, infection with filarial parasites resulted in upregulation of CCL22, a type-2 associated chemokine, both at the mRNA levels and by its observed effect on the frequency of recruited monocytes. CONCLUSIONS/SIGNIFICANCE: Together, our data suggest that SG or recombinant salivary proteins from Pd alter human monocyte function by upregulating selective inflammatory cytokines.


Assuntos
Brugia Malayi/imunologia , Proteínas de Insetos/imunologia , Monócitos/parasitologia , Phlebotomus/imunologia , Saliva/imunologia , Imunidade Adaptativa , Animais , Células Cultivadas , Quimiocina CCL22/genética , Quimiocina CCL22/metabolismo , Coinfecção , Doenças Endêmicas , Filariose/complicações , Filariose/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Imunidade Celular , Leishmaniose Cutânea/complicações , Leishmaniose Cutânea/imunologia , Lipopolissacarídeos/toxicidade , Mali , Monócitos/fisiologia , RNA Mensageiro , Proteínas Recombinantes , Glândulas Salivares , Linfócitos T Auxiliares-Indutores
17.
Acta Trop ; 220: 105953, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33979638

RESUMO

Several light trap devices have been invented and developed to assess the abundance of sand flies. Traps available in the market have different designs and attractant combinations to catch sand fly vectors. We evaluated the efficacy of four commercial light traps and determined the effect of trap placement and carbon dioxide (CO2) on sand fly collection in northern Thailand. Trap evaluations were conducted at two natural caves located in Chiang Rai province, Thailand. In the first part of the study, the efficacies of four trap types including the Centers for Disease Control miniature light trap (CDC LT), Encephalitis Vector Survey trap (EVS), CDC Updraft Blacklight trap (CDC UB), and Laika trap (LK) were evaluated and compared using a Latin square experimental design. The second half of the study evaluated the influence of trap placement and CO2 on sand fly collection. Additionally, CDC LT were placed inside, outside, and at the entrance of caves to compare the number of sand flies collected. For the trap efficacy experiment, a total of 11,876 phlebotomine sand flies were collected over 32 trap-nights. Results demonstrated that CDC LT, CDC UB, and LK collected significantly more sand flies than EVS (P > 0.05). However, there were no significant differences between the numbers of sand flies collected by CDC LT, CDC UB, and LK. A total of 6,698 sand flies were collected from the trap placement and CO2 experiment over 72 trap-nights. Results showed that CO2 did not influence the numbers of sand flies captured (P < 0.05), whereas trap placement at the entrance of the caves resulted in collection of significantly more sand flies than traps placed inside and outside of the caves. We found the CDC LT, CDC UB, and LK without CO2 captured the greatest amount of sand flies. This was particularly observed when traps were placed at the entrance of a cave, perhaps because of the greater passage of stimuli caused by wind flow at the entrance of the cave. The light traps in this study can be used effectively to collect sand fly vectors in northern Thailand.


Assuntos
Dióxido de Carbono , Controle de Insetos/métodos , Phlebotomus , Psychodidae , Animais , Cavernas , Vetores de Doenças , Controle de Insetos/instrumentação , Tailândia
18.
Parasit Vectors ; 14(1): 291, 2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34051839

RESUMO

BACKGROUND: Sand flies are principal vectors of the protozoan parasites Leishmania spp. and are widely distributed in all warmer regions of the world, including the Mediterranean parts of Europe. In Central European countries, the sand fly fauna is still under investigation. Phlebotomus mascittii, a suspected but unproven vector of Leishmania infantum, is regarded as the most widely distributed species in Europe. However, many aspects of its biology and ecology remain poorly known. The aim of this study was to provide new data on the biology and ecology of Ph. mascittii in Austria to better understand its current distribution and potential dispersal. METHODS: Sand flies were collected by CDC light traps at four localities in Austria for 11 (2018) and 15 weeks (2019) during the active sand fly season. Climatic parameters (temperature, relative humidity, barometric pressure and wind speed) were retrospectively obtained for the trapping periods. Sand flies were identified by a combined approach (morphology, DNA barcoding, MALDI-TOF protein profiling), and blood meals of engorged females were analysed by DNA sequencing and MALDI-TOF mass spectrometry. RESULTS: In total, 450 individuals of Ph. mascittii were caught. Activity was observed to start at the beginning of June and end at the end of August with peaks in mid-July at three locations and early August at one location. Increased activity was associated with relatively high temperatures and humidity. Also, more individuals were caught on nights with low barometric pressure. Analysis of five identified blood meals revealed chicken (Gallus gallus) and equine (Equus spp.) hosts. Sand fly abundance was generally associated with availability of hosts. CONCLUSION: This study reports unexpectedly high numbers of Ph. mascittii at selected Austrian localities and provides the first detailed analysis of its ecology to date. Temperature and humidity were shown to be good predictors for sand fly activity. Blood meal analyses support the assumption that Ph. mascittii feeds on mammals as well as birds. The study significantly contributes to understanding the ecology of this sand fly species in Central Europe and facilitates prospective entomological surveys.


Assuntos
Ecologia , Insetos Vetores , Phlebotomus , Estações do Ano , Animais , Áustria , Galinhas , Europa (Continente) , Feminino , Cavalos , Insetos Vetores/parasitologia , Leishmania infantum , Masculino , Phlebotomus/genética , Psychodidae , Estudos Retrospectivos , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
19.
Artigo em Inglês | MEDLINE | ID: mdl-33956595

RESUMO

A Gram-stain-negative, rod-shaped, non-motile, non-spore-forming, aerobic bacterium, designated type strain SSI9T, was isolated from sand fly (Phlebotomus papatasi Scopoli; Diptera: Psychodidae) rearing substrate and subjected to polyphasic taxonomic analysis. Strain SSI9T contained phosphatidylethanolamine as a major polar lipid, MK-7 as the predominant quinone, and C16 : 1ω6c/C16 : 1ω7c, iso-C15 : 0, iso-C17 : 0 3-OH and C16 : 0 as the major cellular fatty acids. Phylogenetic analysis based on 16S rRNA gene sequences revealed that SSI9T represents a member of the genus Sphingobacterium, of the family Sphingobacteriaceae sharing 96.5-88.0 % sequence similarity with other species of the genus Sphingobacterium. The results of multilocus sequence analysis using the concatenated sequences of the housekeeping genes recA, rplC and groL indicated that SSI9T formed a separate branch in the genus Sphingobacterium. The genome of SSI9T is 5 197 142 bp with a DNA G+C content of 41.8 mol% and encodes 4395 predicted coding sequences, 49 tRNAs, and three complete rRNAs and two partial rRNAs. SSI9T could be distinguished from other species of the genus Sphingobacterium with validly published names by several phenotypic, chemotaxonomic and genomic characteristics. On the basis of the results of this polyphasic taxonomic analysis, the bacterial isolate represents a novel species within the genus Sphingobacterium, for which the name Sphingobacterium phlebotomi sp. nov. is proposed. The type strain is SSI9T (=ATCC TSD-210T=LMG 31664T=NRRL B-65603T).


Assuntos
Phlebotomus/microbiologia , Sphingobacterium/classificação , Sphingobacterium/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Fosfatidiletanolaminas/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingobacterium/genética , Sphingobacterium/metabolismo
20.
Parasitol Res ; 120(5): 1571-1582, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33852067

RESUMO

Genus and species of phlebotomine sand flies have been recorded and described in caves in Brazil, but no study has provided the food source used by sand flies in these environments. Herein, we identified the blood source used by sand fly species in caves located at "Quadrilátero Ferrífero" (QF), Minas Gerais state. Specimens were manually collected near or on anurans inside ferruginous caves in Serra do Gandarela National Park and Serra do Rola Moça State Park. Males and females were placed in vials with 70% alcohol and stored at -10°C. Females engorged, after specific identification, had DNA extracted and followed for PCR amplification using specific primers. Sequencing was analyzed in the GenBank and Barcode of Life. A total of 198 specimens were collected (107 females and 91 males), all of them belonging to species Sciopemyia aff. microps (88.89%), Sciopemyia sordellii (10.61%), or Martinsmyia oliveirai (0.50%). When it comes to the females, 89 were S. aff. microps and 18 S. sordellii. Nineteen engorged females of S. aff. microps were analyzed and most of them (n=18) presented blood from Bokermannohyla martinsi and one contained blood from Scinax fuscovarius. The blood present in engorged females of S. sordellii (n=4) was from B. martinsi. Sciopemyia genus specimens are commonly found in collections carried out inside natural caves, but this was the first study to prove that females of this genus feed on cold-blooded animals in nature. HIGHLIGHTS: • Here we proved that sand flies feed in cold-blooded animals in in Brazilian caves. • Females of the Sciopemyia genus were for the first time found feeding in natural habitats. • Anurans of the family Hylidae were identified as source by molecular analyzes. • Insect bloodmeal identification can help assessing the fauna in several biomes. • This is the first record of S. aff. microps in caves of Brazil.


Assuntos
Anuros/parasitologia , Phlebotomus/classificação , Phlebotomus/fisiologia , Animais , Brasil , DNA/genética , Comportamento Alimentar , Feminino , Alimentos , Masculino , Parques Recreativos , Reação em Cadeia da Polimerase
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