ABSTRACT
In an effort to unify the nomenclature of Trypanosoma cruzi, the causative agent of Chagas disease, an updated system was agreed upon at the Second Satellite Meeting. A consensus was reached that T. cruzi strains should be referred to by six discrete typing units (T. cruzi I-VI). The goal of a unified nomenclature is to improve communication within the scientific community involved in T. cruzi research. The justification and implications will be presented in a subsequent detailed report.
Subject(s)
Animals , Terminology as Topic , Trypanosoma cruzi/classificationABSTRACT
Eighteen Trypanosoma cruzi stocks from the state of Paraíba, Brazil, isolated from man, wild mammals, and triatomine bugs were studied by multilocus enzyme electrophoresis and random primed amplified polymorphic DNA. Despite the low number of stocks, a notable genetic, genotypic, and phylogenetic diversity was recorded. The presence of the two main phylogenetic subdivisions, T. cruzi I and II, was recorded. The strong linkage disequilibrium observed in the population under survey suggests that T. cruzi undergoes predominant clonal evolution in this area too, although this result should be confirmed by a broader sample. The pattern of clonal variation does not suggests a recent origin by founder effect with a limited number of different genotypes.
Subject(s)
Animals , Humans , DNA, Protozoan/analysis , Genetic Variation , Trypanosoma cruzi/genetics , Brazil , Clone Cells , Didelphis/parasitology , Electrophoresis, Agar Gel , Genotype , Phylogeny , Random Amplified Polymorphic DNA Technique , Triatoma/parasitology , Trypanosoma cruzi/enzymology , Trypanosoma cruzi/isolation & purificationABSTRACT
Blood transfusion is the second most common transmission route of Chagas disease in many Latin American countries. In Mexico, the prevalence of Chagas disease and impact of transfusion of Trypanosoma cruzi-contaminated blood is not clear. We determined the seropositivity to T. cruzi in a representative random sample, of 2,140 blood donors (1,423 men and 647 women, aged 19-65 years), from a non-endemic state of almost 5 millions of inhabitants by the indirect hemagglutination (IHA) and enzyme linked immunosorbent assay (ELISA) tests using one autochthonous antigen from T. cruzi parasites, which were genetically characterized like TBAR/ME/1997/RyC-V1 (T. cruzi I) isolated from a Triatoma barberi specimen collected in the same locality. The seropositivity was up to 8.5 percent and 9 percent with IHA and ELISA tests, respectively, and up to 7.7 percent using both tests in common. We found high seroprevalence in a non-endemic area of Mexico, comparable to endemic countries where the disease occurs, e.g. Brazil (0.7 percent), Bolivia (13.7 percent) and Argentina (3.5 percent). The highest values observed in samples from urban areas, associated to continuous rural emigration and the absence of control in blood donors, suggest unsuspected high risk of transmission of T. cruzi, higher than those reported for infections by blood e.g. hepatitis (0.1 percent) and AIDS (0.1 percent) in the same region
Subject(s)
Animals , Humans , Adolescent , Adult , Middle Aged , Blood Donors , Chagas Disease , Trypanosoma cruzi , Antibodies, Protozoan , Chagas Disease , Enzyme-Linked Immunosorbent Assay , Hemagglutination Tests , Mexico , Prevalence , Seroepidemiologic Studies , Trypanosoma cruziABSTRACT
La genetique des populations n'est pas seulement pour le parasitologue une discipline de sciences fondamentales; mais elle constitue en fait un detour oblige pour tout chercheur desireux de caracteriser les souches de parasites a l'aide des outils nouveaux apportes par la biochimie et la biologie moleculaire. Refuser ce detour equivaut a chercher a utiliser une machine complexe sans son mode d'emploi
Subject(s)
Biochemistry , Genetics , Molecular Biology , ParasitesABSTRACT
A genetic analysis of a set of Trypanosoma cruzi and Trypanosoma rangeli stocks was performed by two combined approaches, namely multilocus enzyme electrophoresis (MLEE) and labeling by DNA probes. A considerable genetic variability was evidenced within each of the two species. Since the upper level of resolution of the isoenzyme method was reached, it was impossible to draw any definite discrimination between the two species by usual clustering methods. Nevertheless, two markers appeared as species-specific, namely the malic enzyme, and a probe that hybridizes highly-repeated sequences of T. cruzi
Subject(s)
Animals , Dogs , Humans , Genetics, Population , Trypanosoma/genetics , Base Sequence , DNA Probes , DNA, Protozoan/genetics , Electrophoresis/methods , Genotype , Isoenzymes/analysis , Molecular Sequence Data , Nucleic Acid Hybridization , Trypanosoma cruzi/classification , Trypanosoma cruzi/genetics , Trypanosoma/classification , VenezuelaABSTRACT
The authors showed by biological, immunological and biochemical studies, the presence of two leishmania complexes L.braziliensis and L.mexicana, isolated from cutaneous lesions in patients, coming from the tropical zone of Santa Cruz_Bolivia