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The American Journal of Tropical... Feb 2024During an exploratory fieldtrip along the peninsula of Baja California, Mexico, we used mice-baited traps in search of Triatominae, the vectors of Chagas disease. A...
During an exploratory fieldtrip along the peninsula of Baja California, Mexico, we used mice-baited traps in search of Triatominae, the vectors of Chagas disease. A total of 433 traps were set in five localities following a latitude gradient along the peninsula. Triatominae were caught in rocky ecotopes in two localities. The specimens were identified as Paratriatoma hirsuta in the first locality, and Dipetalogaster maxima in the second, in accordance with the reported distributions of these species. The overall trap success was 3.1%, with an average of 1.3 bugs per positive trap. In the site with most bugs collected, trap success was 26.8%. To the best of our knowledge, this is the first time that mice-baited traps have been used in this geographic area to collect Triatominae bugs. This short report confirms the usefulness of this trapping system when standardized protocols are needed.
Topics: Animals; Mice; Triatominae; Mexico; Chagas Disease
PubMed: 38167291
DOI: 10.4269/ajtmh.23-0327 -
Vector Borne and Zoonotic Diseases... Feb 2024In the Amazon region, several species of triatomines occur in the natural environments. Among them, species of the genus are a risk to human populations due to their...
In the Amazon region, several species of triatomines occur in the natural environments. Among them, species of the genus are a risk to human populations due to their high rates of infection with The aim of this study was to identify the genotypes in specimens and their relationship with sylvatic hosts from different environments in the Brazilian Amazon. A total of 492 triatomines were collected from the municipalities of Monte Negro, Rondônia state, and Humaitá, Amazonas state, 382 of them being nymphs and 110 adults. Genotyping of in six discrete typing units (DTUs) was performed using conventional multilocus PCR. The triatomines that were positive for and engorged with blood were also targeted for amplification of the gene to identify bloodmeal sources. Of the 162 positive samples, the identified DTUs were TcI (87.65%) and TcIV (12.35%). It was observed that 102 specimens were engorged with a variety of bloodmeals. Triatomines infected with TcI were associated with DNA of all identified vertebrates, except TcIV was detected in triatomines that fed on , , , , , , and Results highlight the need to understand the patterns of genotypes in spp. and their association with sylvatic hosts to better elucidate their role in the transmission of Chagas disease in the Amazon region.
Topics: Adult; Animals; Humans; Trypanosoma cruzi; Rhodnius; Genotype; Brazil; Chagas Disease
PubMed: 38165392
DOI: 10.1089/vbz.2023.0082 -
The octopamine receptor OAα1 influences oogenesis and reproductive performance in Rhodnius prolixus.PloS One 2023The control of reproductive processes in Rhodnius prolixus involves a variety of neuroactive chemicals. Among these, several studies have suggested that the biogenic...
The control of reproductive processes in Rhodnius prolixus involves a variety of neuroactive chemicals. Among these, several studies have suggested that the biogenic amine octopamine (OA), might play an active role in these processes. Here, we investigate the molecular profile of the R. prolixus α adrenergic-like OA receptor 1 (RpOAα1-R) and its role in egg production. Comparative molecular analyses confirm that the RpOAα1-R gene codes for a true OAα1 receptor. The RpOAα1-R transcript is highly expressed in tissues associated with egg production, and after a blood meal, which is the stimulus for full egg production in R. prolixus, the RpOAα1-R transcript is upregulated in the ovaries and spermatheca. After RNAi-mediated RpOAα1-R knockdown, an ovarian phenotype characterized by slow egg development is observed. Furthermore, an altered egg phenotype has been characterized with eggs that are deformed. Interestingly, there is no evidence of disruption in vitellogenin (Vg) synthesis by the fat body or uptake by the oocytes. On the other hand, RpOAα1-R downregulation is correlated with defective choriogenesis in the eggs. These results provide critical information concerning the role of OAα1-R in oogenesis in R. prolixus.
Topics: Animals; Rhodnius; Oogenesis; Oocytes; Reproduction
PubMed: 38157386
DOI: 10.1371/journal.pone.0296463 -
Heliyon Dec 2023Triatomines are hematophagous insects of epidemiological importance as they are vectors of Chagas disease. The first report of Lent, Jurberg & Galvão, 1993 in...
Triatomines are hematophagous insects of epidemiological importance as they are vectors of Chagas disease. The first report of Lent, Jurberg & Galvão, 1993 in Rondônia, Brazil, is described. The insects were captured on palm trees of the genus sp. Two adult male specimens of were identified and were found to be infected with and . The confirmation of this species in Rondônia increases the number of triatomines from nine to ten species in this state.
PubMed: 38125462
DOI: 10.1016/j.heliyon.2023.e22747 -
Peptides Feb 2024The causative agent for Chagas disease, Trypanosoma cruzi, is transmitted to a human host in the urine/feces of the kissing bug, Rhodnius prolixus, following blood...
Functional characterization of the kinin receptor in the Chagas disease vector Rhodnius prolixus; activity of native kinins and potent biostable Aib-containing insect kinin analogs.
The causative agent for Chagas disease, Trypanosoma cruzi, is transmitted to a human host in the urine/feces of the kissing bug, Rhodnius prolixus, following blood feeding. Kinins are important chemical messengers in the overall control of blood feeding physiology in R. prolixus, including hindgut contractions and excretion. Thus, disruption in kinin signaling would have damaging consequences to the insect but also interfere with the transmission of Chagas Disease. Here, a heterologous functional receptor assay was used to confirm the validity of the previously cloned putative kinin G-protein-coupled receptor, RhoprKR, in Rhodnius prolixus. Three native R. prolixus kinins were chosen for analysis; two possessing the typical kinin WGamide C-terminal motif and one that possesses an atypical C-terminal WAamide. All three are potent (EC values in the nM range), with high efficacy, on CHO-K1-aeq cells expressing the RhoprKR, thereby confirming ligand binding. Members of three other R. prolixus peptide families, which are also myotropins (tachykinins, pyrokinins and sulfakinins) elicited little or no response. In addition, this heterologous receptor assay was used to test characteristics of kinin mimetics previously tested on tick and mosquito kinin receptors. Five α-aminoisobutyric acid (Aib) containing analogs were tested, and four found to have considerably higher potencies than the native kinins, with EC values in the pM range. Interestingly, adding Aib to the atypical WAamide kinin improves its EC value from 2 nM to 39 pM. Biostable kinin analogs may prove useful leads for novel pest control strategies. Since T. cruzi is transmitted to a human host in the urine/feces after blood feeding, disruption in kinin signaling would also interfere with the transmission of Chagas Disease.
Topics: Cricetinae; Animals; Humans; Kinins; Rhodnius; Mosquito Vectors; Chagas Disease; Cricetulus; Disease Vectors
PubMed: 38103839
DOI: 10.1016/j.peptides.2023.171135 -
Insect Biochemistry and Molecular... Feb 2024Blood feeding is a secondary adaptation in hematophagous bugs. Many proteins are secreted in the saliva that are devoted to coping with the host's defense and to process...
Blood feeding is a secondary adaptation in hematophagous bugs. Many proteins are secreted in the saliva that are devoted to coping with the host's defense and to process the blood meal. Digestive enzymes that are no longer required for a blood meal would be expected to be eventually lost. Yet, in many strictly hematophagous arthropods, α-amylase genes, which encode the enzymes that digest starch from plants, are still present and transcribed, including in the kissing bug Rhodnius prolixus (Hemiptera, Reduviidae) and its related species, which transmit the Chagas disease. We hypothesized that retaining α-amylase could be advantageous if the bugs occasionally consume plant tissues. We first checked that the α-amylase protein of Rhodnius robustus retains normal amylolytic activity. Then we surveyed hundreds of gut DNA extracts from the sylvatic R. robustus to detect traces of plants. We found plant DNA in 8% of the samples, mainly identified as Attalea palm trees, where R. robustus are usually found. We suggest that although of secondary importance in the blood-sucking bugs, α-amylase may be needed during occasional plant feeding and thus has been retained.
Topics: Animals; Rhodnius; Chagas Disease; DNA; Triatoma; alpha-Amylases
PubMed: 38101706
DOI: 10.1016/j.ibmb.2023.104059 -
Journal of Medical Entomology Dec 2023Triatomine species (kissing bugs) infected with Trypanosoma cruzi are found across the southern United States. The northern limits of Trypanosoma cruzi infected kissing...
The distribution of triatomine (Hemiptera: Reduviidae) vectors of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) in Illinois and Missouri: historical records and specimen submissions from community science programs.
Triatomine species (kissing bugs) infected with Trypanosoma cruzi are found across the southern United States. The northern limits of Trypanosoma cruzi infected kissing bugs are less understood. The objective of this work was to describe the locations of kissing bugs from Illinois and Missouri based on historical records, submissions to Texas A&M University's (TAMU) Kissing Bug Community Science Program and the Centers for Disease Control and Prevention (CDC), and records from online platforms (iNaturalist, BugGuide, and GBIF) up to and including 2022. A total of 228 records were discovered, including 186 from historical or observation platforms and 42 specimens submitted to TAMU or CDC. Species included Triatoma sanguisuga (221 total records, 9 nymphs) and Triatoma lecticularia (7 records). Notably, nearly all (24/26) records submitted to TAMU were collected indoors. Twelve of the 30 (40%) specimens tested were positive for the presence of T. cruzi, including parasite discrete taxonomic units TcI and TcIV. One triatomine sample had been found in a bed feeding on the submitter; this bug was positive for T. cruzi and had evidence of human blood in its gut. Records suggest a ubiquitous distribution in Missouri and potentially to the northernmost border in Illinois. Further investigations into triatomine distribution and infection status are needed within states assumed to be northern limits in order to create public health and veterinary health messaging and baseline distributional maps from which to measure future range shifts in relation to a changing climate.
PubMed: 38070198
DOI: 10.1093/jme/tjad124 -
Acta Tropica Feb 2024Triatomine insects are vectors of the protozoan parasite Trypanosoma cruzi- the causative agent of Chagas disease. Chagas disease is endemic to Latin America and the...
Triatomine insects are vectors of the protozoan parasite Trypanosoma cruzi- the causative agent of Chagas disease. Chagas disease is endemic to Latin America and the southern United States and can cause severe cardiac damage in infected mammals, ranging from chronic disease to sudden death. Identifying interactions among triatomines, T. cruzi discrete typing units (DTUs), and blood feeding hosts is necessary to understand parasite transmission dynamics and effectively protect animal and human health. Through manual insect trapping efforts, kennel staff collections, and with the help of a trained scent detection dog, we collected triatomines from 10 multi-dog kennels across central and south Texas over a one-year period (2018-2019) and tested a subset to determine their T. cruzi infection status and identify the primary bloodmeal hosts. We collected 550 triatomines, including Triatoma gerstaeckeri (n = 515), Triatoma lecticularia (n = 15), Triatoma sanguisuga (n = 6), and Triatoma indictiva (n = 2), with an additional 10 nymphs and 2 adults unable to be identified to species. The trained dog collected 42 triatomines, including nymphs, from areas not previously considered vector habitat by the kennel owners. Using qPCR, we found a T. cruzi infection prevalence of 47 % (74/157), with T. lecticularia individuals more likely to be infected with T. cruzi than other species. Infected insects harbored two T. cruzi discrete typing units: TcI (64 %), TcIV (23 %), and mixed TcI/TcIV infections (13 %). Bloodmeal host identification was successful in 50/149 triatomines, revealing the majority (74 %) fed on a dog (Canis lupus), with other host species including humans (Homo sapiens), raccoons (Procyon lotor), chickens (Gallus gallus), wild pig (Sus scrofa), black vulture (Coragyps atratus), cat (Felis catus), and curve-billed thrasher (Toxostoma curviostre). Given the frequency of interactions between dogs and infected triatomines in these kennel environments, dogs may be an apt target for future vector control and T. cruzi intervention efforts.
Topics: Animals; Dogs; Humans; Cats; Trypanosoma cruzi; Texas; Insect Vectors; Chickens; Chagas Disease; Triatoma; Mammals
PubMed: 38061614
DOI: 10.1016/j.actatropica.2023.107087 -
Salud Publica de Mexico Mar 2023Sistematizar, evaluar y sintetizar la investigación original específica en México sobre la zoonosis por Trypano-soma cruzi, los vectores (Triatominae: Hemiptera:...
OBJETIVO
Sistematizar, evaluar y sintetizar la investigación original específica en México sobre la zoonosis por Trypano-soma cruzi, los vectores (Triatominae: Hemiptera: Reduviidae) y la enfermedad de Chagas (EC). Material y métodos. La investigación original fue identificada con PRISMA mediante cuatro sistemas de búsqueda, usando criterios de inclusión, se realizó la asignación a 14 áreas temáticas y fue evaluada mediante criterios técnicos.
RESULTADOS
De un total de 1 410 registros, fueron elegidos 659 (46.7%) para la valoración técnica, de los cuales, 221 (15.7%) fueron incluidos como las evidencias de mayor calidad. El buscador PubMed contribuyó con 95% de los registros, mientras que los buscadores BibTri, Lilacs y Scielo aportaron 5%. La tasa de publicación fue constante de 1950 a 1990, con un incremento exponencial de 1995 a 2020. La alta calidad de publicaciones incrementó de 5.3% en 1990 hasta 49.8% en 2020. Los temas de aspectos sistémicos, económicos, antropológicos y sociales de la EC en México fueron los menos representados (8%).
CONCLUSIONES
En las dos últimas décadas en México ha incrementado la investigación científica. Sin embargo, son notables las caren- cias en las áreas para poder fundamentar la política pública sanitaria en cuanto a la atención, la prevención y el control de la EC en el país.
PubMed: 38060863
DOI: 10.21149/14020 -
Biochimica Et Biophysica Acta.... Mar 2024Rhodnius prolixus is a hematophagous insect, which feeds on large and infrequent blood meals, and is a vector of trypanosomatids that cause Chagas disease. After...
Deficiency of Brummer lipase disturbs lipid mobilization and locomotion, and impairs reproduction due to defects in the eggshell ultrastructure in the insect vector Rhodnius prolixus.
Rhodnius prolixus is a hematophagous insect, which feeds on large and infrequent blood meals, and is a vector of trypanosomatids that cause Chagas disease. After feeding, lipids derived from blood meal are stored in the fat body as triacylglycerol, which is recruited under conditions of energy demand by lipolysis, where the first step is catalyzed by the Brummer lipase (Bmm), whose orthologue in mammals is the adipose triglyceride lipase (ATGL). Here, we investigated the roles of Bmm in adult Rhodnius prolixus under starvation, and after feeding. Its gene (RhoprBmm) was expressed in all the analyzed insect organs, and its transcript levels in the fat body were not altered by nutritional status. RNAi-mediated knockdown of RhoprBmm caused triacylglycerol retention in the fat body during starvation, resulting in larger lipid droplets and lower ATP levels compared to control females. The silenced females showed decreased flight capacity and locomotor activity. When RhoprBmm knockdown occurred before the blood meal and the insects were fed, the females laid fewer eggs, which collapsed and showed low hatching rates. Their hemolymph had reduced diacylglycerol content and vitellogenin concentration. The chorion (eggshell) of their eggs had no difference in hydrocarbon amounts or in dityrosine crosslinking levels compared to control eggs. However, it showed ultrastructural defects. These results demonstrated that Bmm activity is important not only to guarantee lipid mobilization to maintain energy homeostasis during starvation, but also for the production of viable eggs after a blood meal, by somehow contributing to the right formation of the egg chorion.
Topics: Animals; Female; Lipase; Rhodnius; Egg Shell; Lipid Mobilization; Reproduction; Triglycerides; Locomotion; Insect Vectors; Mammals
PubMed: 38042331
DOI: 10.1016/j.bbalip.2023.159442