Behavioural biology of Chagas disease vectors

Abstract

Many arthropod species have adopted vertebrate blood as their main food source. Blood is rich in nutrients and, except for the presence of parasites, sterile. However, this food source is not freely available, nor is obtaining it devoid of risk. It circulates inside vessels hidden underneath the skin of mobile hosts that are able to defend themselves and even predate the insects that try to feed on them. Thus, the haematophagous lifestyle is associated with major morphological, physiological and behavioural adaptations that have accumulated throughout the evolutionary history of the various lineages of blood-sucking arthropods. These adaptations have significant consequences for the evolution of parasites as well as for the epidemiology of vector-transmitted diseases. In this review article, we analyse various aspects of the behaviour of triatomine bugs to illustrate how each behavioural trait represents a particular adaptation to their close association with their hosts, which may easily turn into predators. Our aim is to offer to the reader an up-to-date integrative perspective on the behaviour of Chagas disease vectors and to propose new research avenues to encourage both young and experienced colleagues to explore this aspect of triatomine biology.

Circadian modulation of learning abilities in a disease vector insect,Rhodnius prolixus

“…Nevertheless, the persistence of higher learning performance during the subjective night relative to the subjective day, in the absence of external Zeitgeber, constitutes a basis to argue that a circadian clock is modulating PER inhibition learning. This interpretation is consistent with the biologically relevant temporal organisation of triatomine bugs -a salient characteristic of the biology of triatomines being its marked temporal organisation, largely regulated by endogenous circadian clocks (for review, see Lazzari et al, 2013). Selective pressures have acted to adjust the biting activity of blood-sucking insects to the time of the day when hosts are less active (Barrozo et al, 2004).…”

Functional Anatomy of the External and Internal Reproductive Structures in Insect Vectors of Chagas Disease with Particular Reference to Rhodnius prolixus

“…Other researchers have examined physiological processes associated with reproduction [9,10], feeding [11][12][13][14], digestion [15,16] and behaviour [17]. A wealth of knowledge has been gained in close to 100 years of research on this species and with the recent completion of the Rhodnius genome project [18], research on this bug should continue long into the future.…”

Life cycle and vectorial competence of Triatoma williami (Galvão, Souza e Lima, 1965) under the influence of different blood meal sources

“…In fact, a large number of studies about bionomic and behavioral aspects of the Triatomines suggests an increasing interest in establishing control measures and also reflects their use as an excellent biological models for studies about insect hematophagy and physiology (Lazzari et al, 2013).The life cycle of triatomines varies according to the species, the environmental condition and blood meal source (Carbajal de la Fuente et al, 2010;Schofield, 1985), so the general goals of this study were to describe, for the first time, the biological cycle of T.…”