A Common Caatinga Cactus, Pilosocereus gounellei, is an Important Ecotope of Wild Triatoma brasiliensis Populations in the Jaguaribe Valley of Northeastern Brazil

Abstract

Triatoma brasiliensis is the most important vector of Chagas disease in the Caatinga eco-region of northeastern Brazil. Wild T. brasiliensis populations have been reported only from rocky outcrops. However, this species frequently infests/re-infests houses in rock-free sedimentary lowlands. We therefore hypothesized that it should also occupy other natural ecotopes. We show that a common Caatinga cactus, Pilosocereus gounellei, locally known as xiquexique, often harbors T. brasiliensis breeding colonies apparently associated with rodents (n = 44 cacti, infestation rate = 47.7%, 157 bugs captured). Our findings suggest that infested cacti might be involved in house re-infestation by T. brasiliensis in the Caatinga region.

Modeling Disease Vector Occurrence When Detection Is Imperfect II: Drivers of Site-Occupancy by Synanthropic Triatoma brasiliensis in the Brazilian Northeast

“…), Copernicia prunifera palms, cacti ( Pilosocereus gounellei , Cereus jamacaru ), and thorny shrubs. Rocky outcrops were not observed in the study area [12]. The climate is hot and dry, with mean temperatures ∼23–33°C (absolute range, 16–38°C) and rainfall <850 mm/year with periodic severe droughts.…”

“…Assuming that the population in each ecotope was ‘closed’ (no local extinction or colonization) during the short sampling period, this allowed us to estimate bug-detection probabilities and correct for false-negative results [15], [16] (see also Text S1). Overall, 203 discrete ecotopes were surveyed in 32 dwelling compounds, for a total of 609 individual bug-searches; for each ecotope, we noted structural traits (type, building materials, size) and use by vertebrates (see below) on which triatomines could feed (number of individuals or, in the case of rodents, a score measuring the amount of feces present in the ecotope: from 0 if absent to 5 if extremely abundant [12], [19]). In addition, we recorded the time elapsed since each dwelling was last sprayed by professional vector-control staff.…”

Characteristics of Triatomine infestation and natural Trypanosoma cruzi infection in the State of Rio Grande do Norte, Brazil

“…Its occurrence in Northeastern Brazil is associated with rock formation distribution (6) . However, this species can also be found in shrubby cacti co-occupied by native rodents in Ceará (57) .…”

Multiple Approaches to Address Potential Risk Factors of Chagas Disease Transmission in Northeastern Brazil

“…widely distributed in the wild environment, and inhabiting domestic and peridomestic ecotopes. [33][34][35][36] In the Cipó locality, T. brasiliensis remains the prevalent triatomine species representing 99.6% of the captured specimens and present in both sylvatic and domestic environments and frequently associated with other triatomines, such as T. pseudomaculata, P. megistus and R. nasutus. 1,13,16,37,33 However, it is postulated that T. brasiliensis is favored in a niche competition with other species, which may explain the almost exclusive presence of this species in the areas surrounding the studied locality.…”