Flight Behavior and Performance ofRhodnius pallescens(Hemiptera: Reduviidae) on a Tethered Flight Mill

Abstract

Flight dispersal of the triatomine bug species Rhodnius pallescens Barber, the principal vector of Chagas disease in Panama, is an important mechanism for spreading Trypanosoma cruzi, causative agent of Chagas disease. This study measures R. pallescens flight performance using a tethered flight mill both when uninfected, and when infected with T. cruzi or Trypanosoma rangeli. Forty-four out of the 48 (91.7%) insects initiated flight across all treatments, and trypanosome infection did not significantly impact flight initiation. Insects from all treatments flew a cumulative distance ranging from 0.5 to 5 km before fatiguing. The median cumulative distance flown before insect fatigue was higher in T. cruzi- and T. rangeli-infected insects than in control insects; however, this difference was not statistically significant. There was a positive relationship between parasite load ingested and time until flight initiation in T. rangeli-infected bugs, and T. rangeli- and T. cruzi-infected females flew significantly faster than males at different time points. These novel findings allow for a better understanding of R. pallescens dispersal ability and peridomestic management strategies for the prevention of Chagas disease in Panama.

Rhodnius prolixus Life History Outcomes Differ when Infected with Different Trypanosoma cruzi I Strains

“…This parasite concentration is similar to that used in several other published studies of T. cruzi infection in triatomines, 9,44,46,50,[54][55][56][57][58][59] and blood meals taken by triatomines at this parasite concentration lead to infective doses that fall within the range of peak parasitemias observed in mice and guinea pigs experimentally infected with T. cruzi. 25,27,[60][61][62][63] Insect infection: insect preparation and feeding.…”

“…Epimastigote forms of T. cruzi were cultured at 28°C in RPMI-1640 liquid medium (Sigma-Aldrich, St. Louis, MO) supplemented with 10% fetal bovine serum 42,43 and collected in their exponential growth phase for insect infection, as in several similar studies. 9,38,[44][45][46][47][48][49][50][51] To calculate the parasite concentration in culture medium, we gently swished flasks containing the parasites in the medium to facilitate even parasite dispersion. We pipetted the parasites into a 0.5% formalin-phosphate-buffered saline (PBS) solution, and then counted them in a Neubauer cell counter under a compound light microscope.…”

“…Upon death, we macerated and centrifuged each insect, forming an insect-parasite tissue pellet as described in refs. 46,70 and extracted total deoxyribonucleic acid (DNA) from each pellet with a Qiagen DNeasy blood and tissue kit. We followed the kit protocol for tissue extraction, but with an additional hour of lysis in ATL buffer at 56°C, vortexing every 15 minutes.…”

Alteration of the social and spatial organization of the vector of Chagas disease,Triatoma infestans, by the parasiteTrypanosoma cruzi

“…Moreover, T. dimidiata individuals infected with T. cruzi were found to have larger wings than non-infected ones 40 . In R. pallescens, T. cruzi infection did not significantly impact flight initiation, but it was observed that infected females flew significantly faster than males from 30 s to 2 min after flight initiation 41 . The locomotory activity of R. prolixus was decreased by infection: the total number of movements was 20% less than that observed in non-infected insects 42 .…”

Prediction and Prevention of Parasitic Diseases Using a Landscape Genomics Framework

“…Cells conducive to vector movement are corrected based on host distribution in the same manner: if the distance to the nearest cell where host-vector interaction is possible (i.e., where S. stramineus conductivity is non-zero) exceeds maximum parasite carriage distance by the vector (equable to R. ecuadoriensis dispersal range (ca. 2000 m, based on [86]) when infection does not compromise lifespan and movement (e.g., [87,88])), the vector conductivity score is re-coded to zero. Once abridged, host conductivity values are scaled by a coefficient that quantifies host relative to vector competence in dispersing T. cruzi , weighing in factors such as vagility and transmission intensity (e.g., ca.…”