Blocking transmission of vector-borne diseases

Abstract

Vector-borne diseases are responsible for significant health problems in humans, as well as in companion and farm animals. Killing the vectors with ectoparasitic drugs before they have the opportunity to pass on their pathogens could be the ideal way to prevent vector borne diseases. Blocking of transmission might work when transmission is delayed during blood meal, as often happens in ticks. The recently described systemic isoxazolines have been shown to successfully prevent disease transmission under conditions of delayed pathogen transfer. However, if the pathogen is transmitted immediately at bite as it is the case with most insects, blocking transmission becomes only possible if ectoparasiticides prevent the vector from landing on or, at least, from biting the host. Chemical entities exhibiting repellent activity in addition to fast killing, like pyrethroids, could prevent pathogen transmission even in cases of immediate transfer. Successful blocking depends on effective action in the context of the extremely diverse life-cycles of vectors and vector-borne pathogens of medical and veterinary importance which are summarized in this review. This complexity leads to important parameters to consider for ectoparasiticide research and when considering the ideal drug profile for preventing disease transmission.

Orthosteric muscarinic receptor activation by the insect repellent IR3535 opens new prospects in insecticide-based vector control

“…As illustrated in Fig. 1d, the elevation in [Ca 2+ ] i was detected and quantified in two defined fields at membrane cell body level (1) and in the intracellular medium (2). At very low concentration of IR3535 (10 nM), cytofluorescence intensity was only increased at cell membrane level of the DUM neuron whereas there was never significant calcium variation in the intracellular medium ( Fig.…”

“…(d) Images of Fura-2 fluorescence of a single DUM neuron cell body after application of 10 nM IR3535. The elevation in intracellular calcium concentration is measured in parallel at the membrane cell body level (1) and at the intracellular medium level (2). Note that low concentration of IR3535 (10 nM) only induces calcium response in the membrane cell body region.…”

“…(c) At higher concentration, IR3535 induces dual effect on both M1-mAChR orthosteric and allosteric sites, depending on the time of exposure. Within the first seconds, IR3535 stimulates the orthosteric site (1) before interacting with the allosteric site(2). This last effect renders the G protein inactivated (3), which maintains the BgKC functional resulting in the hyperpolarized potential where high-voltage-activated calcium channels remain closed.…”

Insect Transmission of Plant Pathogens: a Systems Biology Perspective

“…Knowledge of these complex interactions allows for the development of tools to block transmission, to rapidly identify important vector populations, and to improve disease management. Blocking pathogen transmission is the next frontier of precision vector-borne disease management strategies ( 9 , 10 ).…”

Vasoactive intestinal peptide degradation might influence Interleukin-17 expression in cardiac chagasic patients

“…In endemic areas, the disease is transmitted mostly by contact with contaminated feces of Triatominae bugs. Disease can also be transmitted by blood transfusion, organ transplantation, ingestion of contaminated food and via the congenital pathway 1 , 2 .…”