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Chagas disease, caused by the infection with the protozoan parasite Trypanosoma cruzi , is clinically manifested in approximately one-third of infected people by inflammatory heart disease (cardiomyopathy) and, to a minor degree, gastrointestinal tract disorders (megaesophagus or megacolon). Chagas disease is a zoonosis transmitted among animals and people through the contact with triatomine bugs, which are found in much of the western hemisphere, including most countries of North, Central and South America, between parallels 45° north (Minneapolis, USA) and south (Chubut Province, Argentina). Despite much research on drug discovery for T. cruzi , there remain only two related agents in widespread use. Likewise, treatment is not always indicated due to the serious side effects of these drugs. On the other hand, the epidemiology and pathogenesis of Chagas disease are both highly complex, and much is known about both. However, it is still impossible to predict what will happen in an individual person infected with T. cruzi , because of the highly variability of parasite virulence and human susceptibility to infection, with no definitive molecular predictors of outcome from either side of the host-parasite equation. In this Minireview we briefly discuss the current state of T. cruzi infection and prognosis and look forward to the day when it will be possible to employ precision health to predict disease outcome and determine whether and when treatment of infection may be necessary. [ABSTRACT FROM AUTHOR]

The family Gymnophthalmidae is a highly diverse Neotropical lizard clade. Although multiple phylogenetic and taxonomic studies have reshaped our understanding of gymnophthalmid systematics and diversity, many groups remain understudied. This is the case for the cercosaurine genus Echinosaura , which includes eight species of small riparian lizards distributed across lower Central America and northern South America. Here, we present a comprehensive phylogenetic analysis of Echinosaura , including DNA data for all species of the genus for the first time. To rigorously test the relationships of all Echinosaura , we have assembled the largest molecular dataset of cercosaurine lizards to date. Our analysis refutes the monophyly of Echinosaura , with E. apodema and E. sulcarostrum not closely related to the remaining species. To remedy the polyphyly of Echinosaura , we describe two new genera for E. apodema and E. sulcarostrum. Morphological distinctiveness and biogeography further support these taxonomic changes. In light of our phylogenetic results, we review the species-level taxonomy of the redefined Echinosaura based on morphological and genetic variation. We resurrect E. centralis and designate a neotype given the absence of type and topotypic material. In addition, we provide taxonomic accounts for each species and analyse their patterns of geographic distribution. [ABSTRACT FROM AUTHOR]

The worldwide spread of carbapenem- and polymyxin-resistant Enterobacterales represents an urgent public-health threat. However, for most countries in the Americas, the available data are limited, although Latin America has been suggested as a silent spreading reservoir for isolates carrying plasmid-mediated polymyxin resistance mechanisms. This work provides an overall update on polymyxin and polymyxin resistance and focuses on uses, availability and susceptibility testing. Moreover, a comprehensive review of the current polymyxin resistance epidemiology in the Americas is provided. We found that reports in the English and Spanish literature show widespread carbapenemase-producing and colistin-resistant Klebsiella pneumoniae in the Americas determined by the clonal expansion of the pandemic clone ST258 and mgrB-mediated colistin resistance. In addition, widespread IncI2 and IncX4 plasmids carrying mcr-1 in Escherichia coli come mainly from human sources; however, plasmid-mediated colistin resistance in the Americas is underreported in the veterinary sector. These findings demonstrate the urgent need for the implementation of polymyxin resistance surveillance in Enterobacterales as well as appropriate regulatory measures for antimicrobial use in veterinary medicine., (Copyright © 2021 Elsevier Ltd and International Society of Antimicrobial Chemotherapy. All rights reserved.)