Browsing by Author "Cattan, Pedro E."

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    Influence of temperature variability on the feeding behavior and blood consumption of Triatoma infestans (Hemiptera: Reduviidae)
    (2024) Alvarez-Duhart, Barbara; Cavieres, Grisel; Gonzalez, Avia; Cattan, Pedro E.; Bozinovic, Francisco; Clavijo-Baquet, Sabrina
    The transmission and incidence of vector-borne diseases rely on vector distribution and life history traits such as survival, fecundity, and feeding. Since arthropod disease vectors are ectotherms, these vital rates are strongly influenced by temperature. Chagas disease is a neglected tropical disease caused by the protozoan parasite, Trypanosoma cruzi. This parasite is transmitted when the feces of the infected triatomine enter the bloodstream of the host. One of the most important vector-species of this disease in the Southern Cone region of South America is Triatoma infestans. In this study, we evaluated the role of constant and variable environmental temperature on the feeding behavior of T. infestans. Fifth-instar nymphs were acclimatized to 4 thermal treatments comprising 2 temperatures (27 degrees C and 18 degrees C) with and without diurnal thermal variability (27 +/- 5 degrees C and 18 +/- 5 degrees C). Individuals were fed weekly for 7 wk to quantify their feeding. Our results showed lower feeding frequency in nymphs acclimatized to cold temperature compared to those from warmer temperature treatments. However, treatments with thermal variability presented a nonlinear effect on feeding, with an increased feeding rate in the cold, variable treatment and a decreased feeding rate in the warm, variable treatment. Individuals maintained under cold treatments, the variable temperature exhibited a higher feeding rate and the lowest amount of ingested blood among all treatments. Thus, natural diurnal temperature variation cannot be ignored if we are to make more accurate T. cruzi transmission risk predictions now and in the future.
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    Presence of Ixodes neuquenensis Ringuelet, 1947 (Acari: Ixodidae) on the endangered Neotropical marsupial Monito del Monte (Dromiciops gliroides Thomas, 1894, Microbiotheria: Microbiotheriidae) at Chiloe Island, Chile
    (2007) Marin-Vial, Paula; Gonzalez-Acuna, Daniel; Celis-Diez, Juan L.; Cattan, Pedro E.; Guglielmone, Alberto A.
    The presence of Ixodes neuquenensis (Ringuelet, Notas Mus la Plata 12:207-216, 1947) (Acari: Ixodidae) parasitizing populations of Dromiciops gliroides Thomas, 1894 (Microbiotheria: Microbiotheriidae) at Chiloe Island confirms that this tick species is established in Chile. No preference of the ticks for sex or age of the host was observed.
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    Renal carriage of Leptospira species in rodents from Mediterranean Chile: The Norway rat (Rattus norvegicus) as a relevant host in agricultural lands
    (2017) Correa, Juana P.; Bucarey, Sergio A.; Cattan, Pedro E.; Landaeta Aqueveque, Carlos; Ramírez Estrada, Juan Carlos
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    Statistical phylogeography of Chagas disease vector Triatoma infestans: Testing biogeographic hypotheses of dispersal
    (2011) Torres-Perez, Fernando; Acuna-Retamar, Mariana; Cook, Joseph A.; Bacigalupo, Antonella; Garcia, Alejandro; Cattan, Pedro E.
    Chagas disease is one of the most important vector-borne diseases in Latin America. The disease, caused by the flagellate protozoan Trypanosoma cruzi, is commonly transmitted to humans by Triatoma infestans in South America. Using mitochondrial DNA sequences, we assessed alternative biogeographic scenarios of dispersal of T. infestans using coalescence simulations. We also assessed phylogeographic structure and spatial genetics of T. infestans in Chile. Two major routes of dispersal in southern South America were supported including a dual-origin of T. infestans in Chile. Phylogeographic analyses identified two primary clades with Chilean haplotypes partitioned into either a northern cluster with Peruvian and Bolivian haplotypes or a north-central cluster with Argentinean and Uruguayan haplotypes. The north-central clade is further divided into two subgroups. Domestic and sylvatic T. infestans in central Chile were not segregated in the phylogeographic reconstruction. Spatial genetic analyses show higher distances in northern Chile, congruent with the presence of two divergent lineages of T. infestans. Phylogenetic evidence does not unequivocally support the hypothesized Bolivian origin of T. infestans, so we discuss alternative scenarios. (C) 2010 Elsevier B.V. All rights reserved.
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    Thermal performance of the Chagas disease vector, Triatoma infestans, under thermal variability
    (2021) Clavijo-Baquet, Sabrina; Cavieres, Grisel; Gonzalez, Avia; Cattan, Pedro E.; Bozinovic, Francisco
    Vector-borne diseases (VBD) are particularly susceptible to climate change because most of the diseases' vectors are ectotherms, which themselves are susceptible to thermal changes. The Chagas disease is one neglected tropical disease caused by the protozoan parasite, Trypanosoma cruzi. One of the main vectors of the Chagas disease in South America is Triatoma infestans, a species traditionally considered to be restricted to domestic or peridomestic habitats, but sylvatic foci have also been described along its distribution. The infestation of wild individuals, together with the projections of environmental changes due to global warming, urge the need to understand the relationship between temperature and the vector's performance. Here, we evaluated the impact of temperature variability on the thermal response of T. infestans. We acclimated individuals to six thermal treatments for five weeks to then estimate their thermal performance curves (TPCs) by measuring the walking speed of the individuals. We found that the TPCs varied with thermal acclimation and body mass. Individuals acclimated to a low and variable ambient temperature (18 degrees C +/- 5 degrees C) exhibited lower performances than those individuals acclimated to an optimal temperature (27 degrees C +/- 0 degrees C); while those individuals acclimated to a low but constant temperature (18 degrees C +/- 0 degrees C) did not differ in their maximal performance from those at an optimal temperature. Additionally, thermal variability (i.e., +/- 5 degrees C) at a high temperature (30 degrees C) increased performance. These results evidenced the plastic response of T. infestans to thermal acclimation. This plastic response and the non-linear effect of thermal variability on the performance of T. infestans posit challenges when predicting changes in the vector's distribution range under climate change.