Vertical stratification of sand fly diversity in relation to natural infections of Leishmania sp. and blood-meal sources in Jamari National Forest, Rondônia State, Brazil

Abstract

Background Almost 1000 cases of American cutaneous leishmaniasis have been registered yearly in Rondônia State, Brazil. Little is known about the Leishmania transmission cycle (vectors and reservoirs) in the state. This study aimed to evaluate sand fly fauna from two vertical stratification layers in order to identify potential vectors and their blood-meal sources. Methods The study was conducted in Jamari National Forest. Sand flies were collected in the canopy (15 m) and at ground level (1 m) using HP light traps during four months, February, April, August and October, 2018. Insects were identified to the species level, and females were subjected to DNA extraction and PCR targeting minicircle k DNA and hsp 70 (for Leishmania detection and species identification), and cytb (to identify blood-meal sources). Exploratory data analysis was used to determine mean of abundance and species richness between stratifications. The hsp 70 and cytb sequences were analyzed and compared with sequences from GenBank. Results Overall, 68 species were identified from 15,457 individuals. On the Potosi trail, 7531 individuals of 49 species were collected; canopy captures totaled 6463 individuals of 46 species, while ground captures totaled 1068 individuals of 38 species. On the Santa Maria trail, 7926 individuals of 61 species were collected; canopy captures totaled 6136 individuals of 51 species, while ground captures totaled 1790 individuals of 53 species. A total of 23 pools were positive for k DNA (canopy n = 21, ground n = 2). Only two samples were sequenced for hsp 70 (both in canopy); one sequence exhibited similarity with Leishmania braziliensis ( Lutzomyia davisi pool) and another with L. naiffi ( Lu. antunesi pool). The cytb fragment was amplified in 11 of 86 samples. Sample sequencing identified cytb DNA from 5 blood-meal sources: Micrastur gilvicollis , Psophia viridis , Tamandua tetradactyla , Homo sapiens and Choloepus didactylus . Conclusions Sand fly fauna is more diverse in the canopy than at ground level. Factors such as blood-meal sources, resting sites, and abiotic components probably contribute to high abundance in the canopy. Our results reinforce the possibility that Lu. antunesi and Lu . davisi participate in Leishmania ...

Revisiting the cave‐dwelling sand flies (Diptera, Psychodidae, Phlebotominae) from Brazil: Diversity and potential role in the transmission of Leishmania Ross, 1903 (Kinetoplastida: Trypanosomatidae)

“…However, until today there is no information about the capacity of this sand fly to support infections with this parasite and, moreover, about their ecological habits in wild environments, in which in few reports, Ny. antunesi has fed in anteaters ( Tamandua tetradactila ) in Rondônia (Leão et al, 2020; Pereira‐Júnior et al, 2019).…”

“…Ny. antunesi has fed in anteaters (Tamandua tetradactila) in Rondônia (Leão et al, 2020;Pereira-Júnior et al, 2019).…”

Blood Feeding Sources of Nyssomyia antunesi (Diptera: Psychodidae): A Suspected Vector of Leishmania (Kinetoplastida: Trypanosomatidae) in the Brazilian Amazon

“… Arias et al (1982) stated that the vertical habitat of a given phlebotomine species tends to be spatially congruent with that of its associated natural hosts. However, given the small sample size of the present study and considering that some blood sources, such as anteaters, sloths, and birds, frequently move between the canopy and ground level, it was not possible to determine whether feeding occurred arboreally ( Leão et al 2020 ). Conversely, DNA from terrestrial rodents has been found in Ny.…”

“…The identification of bloodmeals from phlebotomines using partial sequences from PCR products of the mtDNA cyt b gene is suitable and widely used for this purpose ( Jiménez et al 2013 , Carvalho et al 2017 , Pereira Junior et al 2019 , Doe et al 2020 , Leão et al 2020 , Remadi et al 2020 , Lozano-Sardaneta et al 2021 , Rodrigues et al 2021 , Torchitte et al 2020 ). Six vertebrate species were found to be blood feeding sources of Ny.…”

“…DNA has been habitually found in Ny. antunesi ( Vásquez-Trujillo et al 2008 , Trujillo et al 2013 , Thies et al 2013 , Ogawa et al 2016 , Leão et al 2020 , Araújo-Pereira et al 2020 , Da Silva Costa et al 2021 ).…”