Chagas disease is one of the most important tropical infections in the world and mainly affects poor people. The causative agent is the hemoflagellate protozoan Trypanosoma cruzi, which circulates among insect vectors and mammals throughout the Americas. A large body of research on Chagas disease has shown the complexity of this zoonosis, and controlling it remains a challenge for public health systems. Although knowledge of Chagas disease has advanced greatly, there are still many gaps, and it is necessary to continue generating basic and applied research to create more effective control strategies. The aim of this review is to provide up-to-date information on the components of Chagas disease and highlight current trends in research. We hope that this review will be a starting point for beginners and facilitate the search for more specific information.

The validity of Zamia splendens has been debated, mainly as a result of its synonymy under Z. katzeriana. Field explorations have uncovered previously unknown populations, and some do not appear to match the circumscription of Z. katzeriana. Some populations are morphologically more similar to, and often sympatric with, Z. loddigesii. This study aims at clarifying the morphological and anatomical distinction between the three taxa. To study the morphological variation, a total of 88 individuals from four populations were sampled, these spanning the geographical range of the three cycads in southern Mexico. Univariate, principal component and discriminant analyses of 12 vegetative morphological variables were carried out. To study variation in leaflet anatomy, three individuals per population were analysed for nine anatomical variables and their stomatal index. Standard plant histological techniques and bright field light microscopy were used for observations and measurements of leaflet anatomical variables. Both morphological and anatomical variables were analysed by multivariate statistical methods. Principal component and discriminant analyses on both morphological and anatomical variables and the stomatal index have shown a significant difference between the populations (P = <0.0002) with scatter diagram dispersion indicating three distinctive groups, with Z. katzeriana values consistently intermediate between those of Z. splendens and Z. loddigesii. Some individuals of Z. katzeriana have a leaflet morphology and anatomy similar to Z. loddigesii, yet others resemble Z. splendens. The three taxa comprise distinct species and we propose the acceptance of Z. splendens as independent from Z. katzeriana. The intermediate placement of Z. katzeriana in the analyses suggests a hybrid origin with Z. splendens and Z. loddigesii as putative ancestors.

A wide variety of mammals are involved in the sylvatic cycle of Trypanosoma cruzi, the causative agent of Chagas disease. In many areas in Latin America where T. cruzi is endemic, this cycle is poorly known, and its main reservoirs have not been identified. In this study we analyzed T. cruzi infection in bats and other small mammals from an Ecological Reserve in southeastern Mexico. From January through March 2021, we captured wild individuals to extract cardiac and peripheral blood, and infection was detected by PCR of the mini-exon gene. In bats, the prevalence of infection was 16.36%, while in small mammals the prevalence was 28.57%. All of the samples that were positive for T. cruzi were identified as the TCI genotype. Our findings suggest that this zone, situated at the periphery of urban zones might have epidemiological relevance in the sylvatic cycle of T. cruzi and needs to be monitored. The infection of bats in this area is particularly concerning since the flight pattern of this populations overlaps with human settlements. Despite being subject to conservation protections, there continue to be anthropogenic actions that disturb the study area, which could exacerbate risks to public health.

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Climate change represents a real threat to biodiversity conservation worldwide. Although the effects on several species of conservation priority are known, comprehensive information about the impact of climate change on reptile populations is lacking. In the present study, we analyze outcomes on the potential distribution of the black beaded lizard (Heloderma alvarezi Bogert &amp; Martin del Campo, 1956) under global warming scenarios. Its potential distribution, at present and in projections for the years 2050 and 2070, under both optimistic and pessimistic climate change forecasts, were computed using current data records and seven bioclimatic variables. General results predict a shift in the future potential distribution of H. alvarezi due to temperature increase. The optimistic scenario (4.5 W/m2) for 2070 suggests an enlargement in the species’ distribution as a response to the availability of new areas of suitable habitat. On the contrary, the worst-case scenario (7 W/m2) shows a distribution decrease by 65%. Moreover, the range distribution of H. alvarezi is directly related to the human footprint, which consequently could magnify negative outcomes for this species. Our research elucidates the importance of conservation strategies to prevent the extinction of the black beaded lizard, especially considering that this species is highly threatened by aversive hunting.