Triatoma dimidiata is one of the major vectors of Chagas disease in Latin America. Its range includes Mexico, all countries of Central America, Colombia, and Ecuador. In light of recent genetic analysis suggesting that the possible origin of this species is the Yucatan peninsula, we have analyzed populations from the state of Yucatan, San Luis Potosi, and Veracruz in Mexico, and a population from the southern region of the Yucatan peninsula located in Northern Guatemala, the region of El Peten. Classical morphometry including principal component, discriminant, sexual dimorphism, and wing asymmetry was analyzed. San Luis Potosi and Veracruz populations were indistinguishable while clearly separate from Yucatan and Peten populations. Despite important genetic differences, Yucatan and Peten populations were highly similar. Yucatan specimens were the smallest in size, while females were larger than males in all populations. Only head characters were necessary to distinguish population level differences, although wing fluctuating asymmetry was present in all populations. These results are discussed in light of recent findings suggesting genetic polymorphism in most populations of Triatoma dimidiata south of Chiapas to Ecuador.

Most Latin American countries are making dramatic progress in controlling Chagas disease, through a series of national and international initiatives focusing on elimination of domestic populations of Triatominae, improved screening of blood donors, and clinical support and treatment of persons infected with Trypanosoma cruzi. Some countries, particularly Uruguay, Chile and Brazil, are sufficiently advanced in their programmes to initiate detailed planning of the subsequent phases of Chagas disease control, while others such as Peru, Ecuador, and Mexico, are currently applying only the initial phases of the control campaigns. In this review, we seek to provide a brief history of the campaigns as a basis for discussion of future interventions. Our aim is to relate operational needs to the underlying biological aspects that have made Chagas disease so serious in Latin America but have also revealed the epidemiological vulnerability of this disease.

La mayoría de los países en América Latina está avanzando, con pasos importantes, en las tareas de control de la enfermedad de Chagas por medio de iniciativas nacionales e internacionales enfocadas en la eliminación de poblaciones domésticas de Triatominae, en el tamizaje de la sangre de transfusión, y en el apoyo terapeútico para los casos infectados con Trypanosoma cruzi. Algunos países como Uruguay, Chile y Brasil, están ya adelantados en sus programas y en la planeación de las siguientes fases de vigilancia y control. Sin embargo, otros países como Perú, Ecuador y México se encuentran apenas en las fases iniciales de planeación de las campañas de control. Este ensayo revisa brevemente la historia de las campañas, como fundamento para entender las estrategias para intervenciones futuras. Nuestro propósito es relacionar las necesidades operacionales con los aspectos biológicos que han provocado las dimensiones de la enfermedad de Chagas en toda América Latina, y que también han manifestado su vulnerabilidad epidemiológica.

Most Latin American countries are making dramatic progress in controlling Chagas disease, through a series of national and international initiatives focusing on elimination of domestic populations of Triatominae, improved screening of blood donors, and clinical support and treatment of persons infected with Trypanosoma cruzi. Some countries, particularly Uruguay, Chile and Brazil, are sufficiently advanced in their programmes to initiate detailed planning of the subsequent phases of Chagas disease control, while others such as Peru, Ecuador, and Mexico, are currently applying only the initial phases of the control campaigns. In this review, we seek to provide a brief history of the campaigns as a basis for discussion of future interventions. Our aim is to relate operational needs to the underlying biological aspects that have made Chagas disease so serious in Latin America but have also revealed the epidemiological vulnerability of this disease.

La mayoría de los países en América Latina está avanzando, con pasos importantes, en las tareas de control de la enfermedad de Chagas por medio de iniciativas nacionales e internacionales enfocadas en la eliminación de poblaciones domésticas de Triatominae, en el tamizaje de la sangre de transfusión, y en el apoyo terapeútico para los casos infectados con Trypanosoma cruzi. Algunos países como Uruguay, Chile y Brasil, están ya adelantados en sus programas y en la planeación de las siguientes fases de vigilancia y control. Sin embargo, otros países como Perú, Ecuador y México se encuentran apenas en las fases iniciales de planeación de las campañas de control. Este ensayo revisa brevemente la historia de las campañas, como fundamento para entender las estrategias para intervenciones futuras. Nuestro propósito es relacionar las necesidades operacionales con los aspectos biológicos que han provocado las dimensiones de la enfermedad de Chagas en toda América Latina, y que también han manifestado su vulnerabilidad epidemiológica.

The evolutionary history and times of divergence of triatomine bug lineages are estimated from molecular clocks inferred from nucleotide sequences of the small subunit SSU (18S) and the second internal transcribed spacer (ITS-2) of the nuclear ribosomal DNA of these reduviids. The 18S rDNA molecular clock rate in Triatominae, and Prosorrhynchan Hemiptera in general, appears to be of 1.8% per 100 million years (my). The ITS-2 molecular clock rate in Triatominae is estimated to be around 0.4-1% per 1 my, indicating that ITS-2 evolves 23-55 times faster than 18S rDNA. Inferred chronological data about the evolution of Triatominae fit well with current hypotheses on their evolutionary histories, but suggest reconsideration of the current taxonomy of North American species complexes.