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1.
Acta Trop ; 257: 107273, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38834157

RESUMO

Phlebotomine sand flies are critical vectors of Leishmania parasites, impacting public health significantly. This study focused on assessing the diversity of sand flies in a rural area of El Carmen de Bolívar Municipality, northern Colombia, employing rarefaction curves and Hill numbers to understand potential vector communities and inform environmental management. From January 2018 to April 2019 (five samplings), sand flies were collected using CDC light traps with blue LED in domestic/peridomestic/sylvatic ecotopes, identifying species per Young and Duncan (1994) and Galati (2003). Hill numbers provided diversity estimates across samples, while Principal Component Analysis correlated with environmental factors with phlebotomine species presence and abundance. 8,784 phlebotomine individuals were collected; 56.4 % females and 43.6% males (ratio 3:2). These individuals belonged to eight species: Pintomyia evansi, Psychodopygus panamensis, Lutzomyia gomezi, Micropygomyia cayennensis, Evandromyia dubitans, Psathyromyia aclydifera, Pintomyia serrana, and Pintomyia rangeliana; with Pi. evansi being the most abundant species (74.39 %; 6,530 exemplars). The ANOVA showed no significant differences between phlebotomine sand flies abundances across ecotopes (p = 0.018). Species of epidemiological relevance as Pi. evansi and Lu. gomezi not show a positive correlation with environmental variables evaluated, only Ps. panamensis was positively correlated with precipitation. However, the study emphasizes the need for a continuous sand fly monitoring and research to enhance leishmaniasis control strategies, highlighting the necessity to expand knowledge on phlebotomine diversity and environmental interactions to understand vector ecology and disease dynamics better.


Assuntos
Insetos Vetores , Leishmania , Leishmaniose , Psychodidae , Animais , Colômbia , Psychodidae/classificação , Psychodidae/crescimento & desenvolvimento , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Feminino , Masculino , Leishmania/classificação , Leishmaniose/transmissão , Biodiversidade
2.
J Med Entomol ; 61(5): 1126-1139, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38902893

RESUMO

Leishmaniasis is a zoonoses caused by protozoan parasites belonging to the Leishmania genus that is transmitted to humans through the bite of previously infected phlebotomine sandflies (Diptera:Psychodidae:Phlebotominae). In Brazil, 2 types of leishmaniasis are endemic, tegumentary leishmaniasis (TL) and visceral leishmaniasis (VL). In Baldim, a municipality in the Espinhaço Range Biospere Reserve (ERBR), 5 autochthonous cases of TL, and one autochthonous case of VL were reported from 2017 to 2022. Owing to the lack of data on entomological fauna, we surveyed the occurrence and distribution of phlebotomine sandflies that could act as Leishmania vectors, as well as natural Leishmania infection. During 1 year, 918 sandfly specimens belonging to 12 species were collected. The predominant species was Lutzomyia longipalpis (Lutz & Neiva, 1912) (32.0%), a proven VL agent, followed by Evandromyia evandroi (Costa Lima & Antunes, 1936) (20.7%), Evandromyia cortelezzii (Brèthes, 1923) (17.0%), Nyssomyia whitmani (Antunes & Coutinho, 1939) (12.2%), and Nyssomyia intermedia (Lutz & Neiva, 1912) (10.5%), all putative or proven TL agents. Seasonal fluctuations and endo-exophilic behavior were delineated for the main phlebotomine sandflies. The population of Lu. longipalpis was higher during the coolest and driest months, although different profiles were noted for the other species. Natural Leishmania infection was not detected in any of the 197 phlebotomine sandfly females analyzed. The results were compared with those previously obtained in other municipalities belonging to the ERBR. The presence of Leishmania vectors and human cases of leishmaniasis indicate a risk of Leishmania transmission in the region.


Assuntos
Insetos Vetores , Leishmania , Psychodidae , Brasil , Animais , Psychodidae/parasitologia , Insetos Vetores/parasitologia , Feminino , Leishmania/isolamento & purificação , Masculino , Densidade Demográfica , Distribuição Animal , Leishmaniose/transmissão
3.
Parasit Vectors ; 17(1): 198, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689318

RESUMO

Canine leishmaniasis is a widespread disease on the American continent, with cases reported from Uruguay to the USA and Canada. While numerous Leishmania spp. have been reported in dogs in this region, Leishmania infantum and Leishmania braziliensis are the most common etiological agents of canine leishmaniasis from a continental perspective. Nonetheless, other species may predominate locally in some countries. The participation of dogs in the transmission cycle of various Leishmania spp. has long been speculated, but evidence indicates that their role as reservoirs of species other than L. infantum is negligible. Various native wildlife (e.g., small rodents, marsupials, sloths, and monkeys) are, in fact, the primary hosts of Leishmania spp. in the Americas. In this review, an updated list of Leishmania spp. infecting dogs in the Americas is presented, along with their distribution and clinical and zoonotic importance.


Assuntos
Doenças do Cão , Leishmaniose , Zoonoses , Animais , Cães , Humanos , América/epidemiologia , Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/veterinária , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Doenças do Cão/epidemiologia , Leishmania/patogenicidade , Leishmaniose/epidemiologia , Leishmaniose/transmissão , Leishmaniose/veterinária , Zoonoses/transmissão , Zoonoses/parasitologia
4.
Med Vet Entomol ; 36(2): 203-211, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35229900

RESUMO

The present study is a comparative analysis of DNeasy Blood & Tissue Qiagen® kit (Qiagen®, Hilden, Alemanha), salting out, HotShot and phenol-chloroform protocols to extract DNA from sandflies. In addition, a comparative test using sandflies with and without eyes evaluated the potential inhibitory effect in the cPCR. An inhibition test was performed using an exogenous DNA added to the qPCR. The genomic DNA quality of each sample was evaluated by cPCR based on the cytochrome c oxidase subunit I (cox1) gene. The DNA extraction protocols showed the following percentage of amplification: HotShot (91.6% [55/60]), salting out (71.6% [43/60]), phenol-chloroform (95% [57/60]) and kit DNeasy Blood & Tissue Qiagen® (73.3% [44/60]). The phenol-chloroform method achieved a significantly higher frequency of cox1 gene amplification. The pigment present in the phlebotomine's eyes seems to inhibit cPCR reactions since the frequency of amplification of the cox1 gene increased in the sandflies without eyes (p < 0.0001). The HotShot method showed the highest inhibitory potential. These manual extraction techniques can be an inexpensive and effective alternative to study vector-pathogen interactions.


Assuntos
Psychodidae , Animais , Clorofórmio , DNA/genética , Genômica , Fenol , Psychodidae/genética
5.
Med Vet Entomol ; 36(2): 176-184, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35089617

RESUMO

The study aimed to develop a multiplex qPCR to detect Leishmania infantum load in different sandfly sample settings using Leishmania kDNA and sandfly vacuolar ATPase (VATP) subunit C as internal control gene. The amplification of Lutzomyia longipalpis VATP gene was evaluated together with Leishmania infantum kDNA in a multiplex reaction. The concentration of VATP gene oligonucleotides was adjusted until no statistically significant difference was observed between all multiplex standard curves and singleplex curves, that is, only kDNA amplification. Limit of detection (LoD) was measured using a probit model and a cut-off defined by receiver operating characteristic analysis. Limit of quantification (LoQ) was assessed by a linear model using the coefficient of variation threshold of 25%. After assuring VATP gene amplification, its primer-probe concentrations were best at 100 nM/10 nM, respectively. The cut-off Cq value for L. infantum kDNA was defined as 35.46 with 100% of sensitivity and specificity. A total of 95% LoD was determined to be of 0.162 parasites while LoQ was 5.858. Our VATP/kDNA multiplex qPCR assay shows that it can be used to evaluate both DNA integrity and determine L. infantum load in L. longipalpis even for low yielded samples, that is, individual midguts.


Assuntos
Leishmania infantum , Phlebotomus , Psychodidae , Animais , DNA de Cinetoplasto/genética , Leishmania infantum/genética , Psychodidae/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
6.
Neotrop Entomol ; 51(2): 311-323, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34936066

RESUMO

Phlebotominae are small insects distributed in the Americas from Canada to Argentina and Uruguay, counting with more than 500 neotropical species. Some of them have a vectorial role in the transmission of Leishmania Ross, the causative agent of leishmaniases, a group of worldwide distributed diseases with different clinical manifestations and transmission cycles. Our aim was to update the Phlebotominae fauna of Argentina and to make observations on the American Cutaneous (ACL) and Visceral Leishmaniasis (AVL) transmission scenarios, according to the distribution of proven or suspected Leishmania vector species and recent changes in land use. Primary data (entomological captures) and secondary data (review of 65 scientific publications with Phlebotominae records) were used. With 9 new records, 46 Phlebotominae species are now recorded through the area comprising 14 political jurisdictions and 6 phytogeographic provinces. Distribution maps were constructed for the 5 proven or incriminated Leishmania vector species, and the evidence supporting the vectorial incrimination of these species is discussed. Three main ACL transmission scenarios are described in the phytogeographic provinces of the Yungas, Chaco, and Paranaense, associated with deforestation processes, while the transmission scenarios of AVL are urban outbreaks and scattered cases in rural areas. We update the available knowledge on the Phlebotominae fauna present in Argentina, emphasizing its epidemiological relevance in the current context of the increasing frequency of ACL outbreaks and geographic spread of AVL.


Assuntos
Leishmaniose Visceral , Leishmaniose , Psychodidae , Animais , Argentina/epidemiologia , Leishmaniose/veterinária , Leishmaniose Visceral/veterinária , Uruguai
7.
Vector Borne Zoonotic Dis ; 22(2): 108-113, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34898260

RESUMO

Background and Objectives: Species of Leishmania genus are intracellular parasites responsible for severe zoonotic diseases worldwide, such as leishmaniasis. In Brazil, the most important species is Leishmania infantum. In the northern region, the state of Pará is notable, with a high number of cases reported in recent years. The second largest number of cases of human visceral leishmaniasis in the region in recent years has been reported in the city of Marabá (Pará state). We investigated the prevalence of L. infantum in domestic dogs from Marabá in Amazon region in Brazil. Materials and Methods: A total of 400 blood samples were tested using the dual-path platform chromatographic immunoassay (DPP® CVL-Bio-Manguinhos), and molecular diagnosis based in cathepsin L-like gene, which has better specificity and sensitivity than other similar tests. Results: The prevalence of L. infantum was 75.5% (302/400) in the serological test, and 59.25% (237/400) in molecular diagnosis, and 45.5% (182/400) in both tests. Interpretation and Conclusion: The results confirmed that the parasite L. infantum was prevalent in the dog population of the studied region and adoption of appropriate public policies are urgently needed.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Animais , Anticorpos Antiprotozoários , Brasil/epidemiologia , Doenças do Cão/parasitologia , Cães , Ecossistema , Leishmania infantum/genética , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Prevalência
8.
Med Vet Entomol ; 35(4): 607-616, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34747526

RESUMO

A new species of phlebotomine sand fly collected in the rural and peri-urban areas of wet and dry subregions of the Chaco Province, Argentina, is described. Illustrations of male and female adults are presented. Morphological characters allow the inclusion of the new species within the Evandromyia genus, Barrettomyia subgenus, Cortelezzii series (Diptera: Psychodidae). Furthermore, we present an identification key for the Cortelezzii series of the Barrettomyia subgenus with a new distinct species complex for its correct identification. The species was denominated as Evandromyia cristacapita sp. nov.


Assuntos
Phlebotomus , Psychodidae , Animais , Argentina , Brasil , Feminino , Masculino
9.
Acta Trop ; 223: 106103, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34416187

RESUMO

The species richness of Amazonian phlebotomines is considered to be one of the highest in the world. In the present study, we investigated the richness and diversity of phlebotomine fauna in Xapuri city, Acre state, Western Brazilian Amazonia, which is an area that is highly endemic for cutaneous leishmaniasis. Sand fly collections were performed monthly from August 2013 to July 2015 (288 h total of sampling effort) in intradomiciliary, peridomiciliary, and forested environments of two localities. Collected females were dissected, microscopically examined for flagellates in their guts, and preserved in ethanol. A total of 21,197 specimens comprising 14 genera and 57 species were collected, and the majority of these were Nyssomyia, Psychodopygus, and Trichophoromyia genera. Three new records of phlebotomine species for Acre are presented here, including Brumptomyia brumpti, Psathyromyia pradobarrientosi, and for the first time in Brazil, Th. omagua. In Xapuri, the phlebotomine fauna of different ecotopes was varied in regard to abundance, diversity, and frequency, and they included proven and permissive vectors of Leishmania spp. The fauna discovered in the forested areas (57 species) was richer and more diverse than was that (33 species) identified in the peri­ and intra-domiciles. The identification of Leishmania subgenera that were present in sand fly guts according to SSU rRNA sequences revealed ten and three species harboring Leishmania of subgenera Viannia and Leishmania (most likely Leishmania amazonensis), respectively. The presence of Leishmania (Leishmania) in sand flies are reported here for the first time in Acre. The presence of L. (Viannia) spp. in Brumptomyia sp. and Lutzomyia sherlocki. and the occurrence of mixed infections with Leishmania of both subgenera in Ps. lainsoni have been reported for the first time in Brazil. Taken together, data from previous studies and from the present study highlight the remarkable complexity of phlebotomine fauna that is possibly due to the well-preserved Xapuri forested areas sustaining vital economic activities of plant extraction and ecological tourism. Our findings also provide new insights into the ongoing adaptation of Trichophoromyia and Psychodopygus species to human habitats.


Assuntos
Leishmania , Psychodidae , Animais , Brasil/epidemiologia , Feminino , Florestas , Humanos , Leishmania/genética , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Psychodidae/parasitologia
10.
J Med Entomol ; 58(4): 1917-1925, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-33822113

RESUMO

Studies on experimental sand fly infection require the availability of colonies and laboratory conditions. In Brazil, Lutzomyia longipalpis (Diptera: Psychodidae) (Lutz and Neiva 1912) is responsible for the highest infection rates by Leishmania spp. and this species is one of the most suitable species for laboratory colonization. In this study, we describe a method for growing Lu. longipalpis in laboratory conditions (10 generations) from natural populations sampled from a region of high endemicity for visceral leishmaniasis in the state of Maranhão, Northeastern Brazil. Using two methods (individualized or grouped females), the colony's highest productivity occurred in the first four generations, where all stages presented with high frequency. Nonviable eggs represented more than 50% of the total eggs produced by engorged females, while pupae were more resistant to fungal contamination, with a mortality rate of only 2%. In both methods, there was a predominance of female emergence; however, the ratio between males and females did not show significant differences, IF (P = 0.8023) and GF (P = 0.1831). Using the method of individualized females, the F4 generation took the longest to appear (234 d; 64 ± 57 d); by grouped females, F3 took the longest to appear (102 d; 47 ± 20 d). This method provides sufficient numbers of insects to perform vector competence tests for Leishmania spp. that cause the cutaneous form of leishmaniasis, usually found in Lu. longipalpis sampled from the study location.


Assuntos
Insetos Vetores/crescimento & desenvolvimento , Psychodidae/crescimento & desenvolvimento , Animais , Bioensaio/métodos , Fertilidade , Laboratórios , Leishmania , Leishmaniose/transmissão , Psychodidae/parasitologia , Razão de Masculinidade
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