Trypanosoma cruzi could affect wild triatomine approaching behaviour to humans by altering vector nutritional status: A field test

Estay-Olea, Daniela; Correa, Juana P.; Bona, Sophie De; Bacigalupo, Antonella; Quiroga, Nicol; Juan, Esteban San; Solari, Aldo; Botto‐Mahan, Carezza

doi:10.1016/j.actatropica.2020.105574

Cited by 19 publications

(16 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Parasites impose additional nutritional requirements on bugs, as supported by the positive correlation between blood consumption and amount of trypomastigotes found in the rectum in T. infestans [28]. This idea is reinforced by a recent study that showed that T. cruzi-infected M. spinolai captured in the field showed a lower nutritional status [29]. The present results enrich our understanding of triatomine foraging, as infection status did not affect the proportion of nymphs that left the shelter in the presence of host cues.…”

Section: Plos Neglected Tropical Diseasesmentioning

confidence: 94%

Trypanosoma cruzi-infected Rhodnius prolixus endure increased predation facilitating parasite transmission to mammal hosts

2021

View full text Add to dashboard Cite

Triatomine bugs aggregate with conspecifics inside shelters during daylight hours. At dusk, they leave their refuges searching for hosts on which to blood feed. After finding a host, triatomines face the threat of being killed, because hosts often prey on them. As it is known that many parasites induce the predation of intermediate hosts to promote transmission, and that ingestion of Trypanosoma cruzi-infected bugs represents a very effective means for mammal infection, we hypothesized that trypanosomes induce infected bugs to take increased risk, and, as a consequence, be predated when approaching a host. Therefore, we evaluated whether the predation risk and predation rates endured by Rhodnius prolixus increase when infected with T. cruzi. Assays were performed in square glass arenas offering one central refuge to infected and uninfected 5th instar nymphs. A caged mouse was introduced in each arena after a three-day acclimation interval to activate sheltered insects and induce them to approach it. As hypothesized, a significantly higher proportion of infected insects was predated when compared with uninfected ones (36% and 19%, respectively). Indeed, T. cruzi-infected bugs took higher risk (Approximation Index = 0.642) when compared with healthy ones (Approximation Index = 0.302) and remained outside the shelters when the host was removed from the arena. Our results show that infection by T. cruzi induces bugs to assume higher risk and endure higher predation rates. We reveal a hitherto unknown trypanosome-vector interaction process that increases infected bug predation, promoting increased rates of robust oral transmission. The significant consequences of the mechanism revealed here make it a fundamental component for the resilient maintenance of sylvatic, peridomestic and domestic cycles.

show abstract

Section: Plos Neglected Tropical Diseasesmentioning

confidence: 94%

Trypanosoma cruzi-infected Rhodnius prolixus endure increased predation facilitating parasite transmission to mammal hosts

2021

View full text Add to dashboard Cite

show abstract

“…Estay-Olea et al [ 61 ] observed for the same triatomine species that nutritional status of uninfected triatomines was higher than that from infected ones, strengthening the hypothesis that triatomines infected with T . cruzi need more blood for molting and excreting during/after a blood meal than uninfected individuals, probably to compensate the nutrients consumed by trypanosomes [ 61 ].…”

Section: Discussionmentioning

confidence: 86%

“…Botto-Mahan et al [59] observed an increased biting rate in M. spinolai infected with T. cruzi compared to non-infected specimens, although the parasite did not interfere on the time interval until the first feeding attempt [59], or in the volume of ingested blood [60]. Estay-Olea et al [61] observed for the same triatomine species that nutritional status of uninfected triatomines was higher than that from infected ones, strengthening the hypothesis that triatomines infected with T. cruzi need more blood for molting and excreting during/after a blood meal than uninfected individuals, probably to compensate the nutrients consumed by trypanosomes [61].…”

Section: Discussionmentioning

confidence: 98%

Vector competence and feeding-excretion behavior of Triatoma rubrovaria (Blanchard, 1843) (Hemiptera: Reduviidae) infected with Trypanosoma cruzi TcVI

et al. 2020

View full text Add to dashboard Cite

Background Several studies addressed changes on the insect vector behavior due to parasite infection, but little is known for triatomine bugs, vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. We assessed infection rates and metacyclogenesis of T. cruzi (TcVI) in fifth-instar nymphs of Triatoma rubrovaria comparing with the primary vector Triatoma infestans. Also, biological parameters related to feeding-excretion behavior were evaluated aiming to identify which variables are most influenced by T. cruzi infection. Methodology/principal findings Fifth-instar nymphs of T. rubrovaria and T. infestans were fed on mice infected with T. cruzi (TcVI). We compared the presence and the number of parasite evolutive forms in excreta of both triatomine species at 30, 60 and 90 days post-infection (dpi) with traditional statistical analyses. Moreover, both species were analyzed through generalized linear models and multinomial logistic regression hypotheses for seven behavioral parameters related to hostseeking and feeding-excretion. Triatoma rubrovaria and T. infestans had similar overall infection and metacyclogenesis rates of T. cruzi TcVI in laboratory conditions. Regarding vector behavior, we confirmed that the triatomine's tendency is to move away from the bite region after a blood meal, probably to avoid being noticed by the vertebrate host. Interspecific differences were observed on the volume of blood ingested and on the proportion of individuals that excreted after the blood meal, revealing the higher feeding efficiency and dejection rates of T. infestans. The amount of ingested blood and the bite behavior of T.

show abstract

“…All captured nymphs showed evidence of starvation by the shape of their abdomens, i.e. they were flat or slightly concave (Estay‐Olea et al ., 2020). Two days after capture, six fourth and fifth stage nymphs were allowed to feed on an anesthetised laboratory mouse ( Mus musculus ) placed in a rectangular glass container (19 × 10 cm) for 30 min.…”

Section: Methodsmentioning

confidence: 99%

Bloodmeal‐stealing in wild‐caught Mepraia spinolai (Hemiptera: Reduviidae), a sylvatic vector of Trypanosoma cruzi

Garrido

Campos‐Soto

Quiroga

et al. 2020

Ecological Entomology

Self Cite

View full text Add to dashboard Cite

1. Blood‐feeding bugs in the Triatominae are the vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. Mepraia is a sylvatic genus endemic to Chile that transmits T. cruzi in the wild cycle. 2. Bloodmeal‐stealing (or ‘cleptohaematophagy’) is the stealing of a bloodmeal from one bug's gut by another, usually conspecific bug. Bloodmeal‐stealing can result in horizontal transmission of T. cruzi between triatomines; so far, it has been reported only in laboratory‐reared bugs. 3. We performed short laboratory experiments to test whether bloodmeal‐stealing occurs between wild‐caught Mepraia spinolai nymphs. Successful bloodmeal‐stealing was observed in one out of 17 trials (2/102 bugs). Even though bloodmeal‐stealing was not frequent in wild‐caught M. spinolai, this behaviour might contribute to explaining the maintenance of wild T. cruzi cycles.

show abstract

Trypanosoma cruzi could affect wild triatomine approaching behaviour to humans by altering vector nutritional status: A field test

Cited by 19 publications

References 43 publications

Trypanosoma cruzi-infected Rhodnius prolixus endure increased predation facilitating parasite transmission to mammal hosts

Trypanosoma cruzi-infected Rhodnius prolixus endure increased predation facilitating parasite transmission to mammal hosts

Vector competence and feeding-excretion behavior of Triatoma rubrovaria (Blanchard, 1843) (Hemiptera: Reduviidae) infected with Trypanosoma cruzi TcVI

Bloodmeal‐stealing in wild‐caught Mepraia spinolai (Hemiptera: Reduviidae), a sylvatic vector of Trypanosoma cruzi

Contact Info

Product

Resources

About