Chagas disease, caused by the protozoan Trypanosoma cruzi and transmitted by triatomine insect vectors, affects about 10 million people worldwide (Schmunis 2000) and is the third most important global parasitic disease after malaria and schistosomiasis (World Bank 1993). Because of effective vector control campaigns, the number of acute cases has decreased markedly and has been reduced to nearly zero in previously highly endemic areas of Uruguay, Chile and Brazil (Schofield et al. 2006).The Chagas disease vector Triatoma infestans (Klug 1834) was historically considered an e�clusively do-) was historically considered an e�clusively domestic insect, but it has now been reported in sylvan environments (Noireau et al. 2005, Noireau 2009). The first sylvatic population of T. infestans was reported in Cochabamba, Bolivia, inhabiting rock piles associated with wild guinea pigs (Torrico 1946). Other reports have shown T. infestans in Argentina (Mazza & Schreiber 1938, Mazza 1943, Ceballos et al. 2009), Paraguay (Velasquez & González 1959 and Brazil (Barretto et al. 1963) under rocks or trunks of fallen trees, in hollow trees, under bark, in shelters or burrows of marsupials and rodents and in bird nests occupied by owls, parrots or small rodents (Noireau et al. 1997). Wild T. infestans has been found in an e�tended geographical region throughout Chaco and three Andean departments of Bolivia: Cochabamba, La Paz and Potosí (Noireau et al. 1999, Cortez et al. 2007. T. infestans was considered to be eradicable due to its strictly domestic behavior and its non-autochthonous status outside of its apparent centre of origin in the Andean valleys of Bolivia. This theory has been challenged by empirical evidence of wild individuals collected by vector control programs and researchers over several decades (Gürtler 2009). Sylvatic triatomines may occasionally invade human residences, acting as founders of new colonies (Fitzpatrick et al. 2008). Hence, it is necessary to study the ecology and behavior of their populations to understand the domiciliation process and generate new strategies for their control (Beard et al. 2002, Guhl et al. 2009, Moncayo & Silveira 2009).In Chile, parasite transmission from vectors to humans occurs mainly in rural and suburban areas encompassing the northern desert and semiarid and Mediterranean environments, between latitudes 18°30'S and 34°36'S. The triatomine insects T. infestans, Mepraia spinolai (Porter 1934) and Mepraia gajardoi are the vector species that have been reported in that area (Spinola 1852, Neghme 1982, Lent et al. 1994, Frias et al. 1998.In 1991, several countries of South America, including Chile, established the Southern Cone Initiative for control of Chagas disease (INCOSUR-Chagas), which provided united strategy, control actions and an information system used to evaluate local control programs (Silveira 2002). The specific aims of the initiative were the following: (i) the elimination of T. infestans from dwellings and their surroundings in endemic areas, (ii) the reduction an...

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Objective The aim of this study was to investigate whether the level, rate, and acceleration of BMI growth differ according to the presence or absence of adult cardiometabolic (CM) risks. Methods BMI was measured in 1,000 Chileans at nine time points from birth to 23 years, and metabolic syndrome and its components were assessed at young adulthood. BMI growth was analyzed in the following three developmental periods: birth to 6 months, 6 months to 5 years, and 5 to 23 years. Results Individuals with CM risks had a specific constellation of early‐life growth (faster growth after infancy, lower BMI decline approaching age 5, absence of a definitive BMI nadir in early childhood, higher 5‐year BMI) and distinct young adult growth (larger BMI increases from childhood to young adulthood and lower levels of expected growth deceleration approaching young adulthood). Those with CM risks also attained BMI ≥ 25 at significantly younger ages than those absent risks (metabolic syndrome: 12.3 years vs. 20.1 years; hyperglycemia: 13.1 years vs. 18.9 years; hypertension: 13.2 years vs. 19.4 years; hypertriglyceridemia: 14.3 years vs. 19.5 years; inflammation: 15.9 years vs. 20.6 years). Conclusions Larger and faster increases in BMI and a failure of BMI growth to decline or decelerate at specific developmental periods distinguished individuals who would and would not have adult CM risks.

Aims: Metabolic syndrome (MetS) is a cluster of risk factors for cardiometabolic diseases. While cigarette smoking is associated with MetS in adults, young adulthood is an under-studied, susceptible period for developing long-term morbidity from MetS. We examined associations between cigarette smoking and MetS risk factors. Methods: We studied 430 participants in Santiago, Chile who have been followed in a longitudinal cohort since infancy and assessed in adolescence for MetS. Participants were evaluated at 22 years from May 2015 to July 2017. Adiposity, blood pressure, and blood samples were measured. MetS was defined using International Diabetes Federation criteria. A continuous MetS score was calculated using z-scores. Participants self-reported cigarette and alcohol consumption using standardized questionnaires. We used multivariate regressions to examine associations between smoking and MetS risk factors, adjusting for sex, MetS in adolescence, alcohol consumption, and socioeconomic status. Results: Thirteen percent of participants had MetS and 50% were current smokers. Among smokers, mean age of initiation was 14.9 years and consumption was 29 cigarettes weekly. Smokers had larger waist circumferences, higher BMIs, and lower high-density lipoprotein (HDL) cholesterol compared to non-smokers. Being a current smoker was significantly associated with higher waist circumference (β = 2.82; 95% CI 0.63, 5.02), lower HDL (β = −3.62; 95% CI −6.19, −1.04), higher BMI (β = 1.22; 95% CI 0.16, 2.28), and higher MetS score (β = 0.13, 95% CI 0.02, 0.24).

Background Trypanosoma cruzi is a protozoan parasite that is transmitted by triatomine vectors to mammals. It is classified in six discrete typing units (DTUs). In Chile, domestic vectorial transmission has been interrupted; however, the parasite is maintained in non-domestic foci. The aim of this study was to describe T . cruzi infection and DTU composition in mammals and triatomines from several non-domestic populations of North-Central Chile and to evaluate their spatio-temporal variations. Methodology/Principal findings A total of 710 small mammals and 1140 triatomines captured in six localities during two study periods (summer/winter) of the same year were analyzed by conventional PCR to detect kDNA of T . cruzi . Positive samples were DNA blotted and hybridized with specific probes for detection of DTUs TcI, TcII, TcV, and TcVI. Infection status was modeled, and cluster analysis was performed in each locality. We detected 30.1% of overall infection in small mammals and 34.1% in triatomines, with higher rates in synanthropic mammals and in M . spinolai . We identified infecting DTUs in 45 mammals and 110 triatomines, present more commonly as single infections; the most frequent DTU detected was TcI. Differences in infection rates among species, localities and study periods were detected in small mammals, and between triatomine species; temporally, infection presented opposite patterns between mammals and triatomines. Infection clustering was frequent in vectors, and one locality exhibited half of the 21 clusters found. Conclusions/Significance We determined T . cruzi infection in natural host and vector populations simultaneously in a spatially widespread manner during two study periods. All captured species presented T . cruzi infection, showing spatial and temporal variations. Trypanosoma cruzi distribution can be clustered in space and time. These clusters may represent different spatial and temporal risks of transmission.