Synanthropic triatomines in Hidalgo state, Mexico: Spatial-temporal distribution, domestic transmission cycle, and natural infection with Trypanosoma cruzi.

Triatomine vectors are responsible for the main route of transmission of the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. This illness is potentially life-threatening and highly disabling and represents a major public health concern in the endemic countries in Latin America. The analysis of the spatial and temporal occurrence of triatomine insects is critical, since control strategies strongly depend on the vector species found within each area. Such knowledge is non-existent in Hidalgo state, an endemic region of Chagas disease in Mexico. A Geographic Information System (GIS) was used to analyze broad-scale spatial and temporal patterns of synanthropic triatomines collected in Hidalgo. Data was taken from the Institute of Epidemiological Diagnosis and Reference (InDRE) of Mexico and the state program of Vector Control of the Secretary of Health, covering the period of 1997-2019. Our analyses demonstrate a differential distribution of Triatoma dimidiata, T. mexicana, T. gerstaeckeri and T. barberi, which are the four predominant species, and that climate, temperature, and precipitation are some of the drivers of their distribution pattern. Notably, we report the presence of T. nitida, T. pallidipennis and T. phyllosoma for the first time in the state. In addition, we found seasonal variations of the populations of T. mexicana and T. gerstaeckeri, but not for T. dimidiata, whose population remains constant throughout the year. The insects were found mainly intradomicile (81.79%), followed by peridomicile (17.56%) and non-domestic areas (0.65%), with an average T. cruzi infection of 16.4%. Based on this evidence, priority sites for vector control intervention were identified. Our findings are very valuable for understanding the epidemiology of Chagas disease, the generation of future potential risk maps and for the development and implementation of effective and targeted vector control programs in Hidalgo state.

[Application of population genetics in the field of medicine]. / Aplicación de la genética de poblaciones en el ámbito de la medicina.

Human populations follow the same evolutionary principles as other organisms, although mixed with social and cultural elements, which can result in a high prevalence of certain diseases within specific ethnic groups. In this work, the Hardy-Weinberg principle is analyzed from a medical, social and biological viewpoint to understand the evolutionary processes of autosomal recessive diseases. It can be concluded that the incidence of these diseases is inversely related to the levels of genetic variability within populations, which depends on colonization, recolonization and migration events, as well as on social conventions such as racism, social stratification and segregation.

Aplicación de la genética de poblaciones en el ámbito de la medicina / Application of population genetics in the field of medicine

Las poblaciones humanas obedecen a los mismos supuestos evolutivos que el resto de los organismos, aunque mezclados con elementos sociales y culturales que pueden promover la expresión de ciertas enfermedades en grupos étnicos específicos, causadas principalmente por la frecuente endogamia. En este trabajo se analiza el principio de Hardy-Weinberg desde un enfoque médico, social y biológico, para entender los procesos evolutivos que dan lugar a las enfermedades autosómicas recesivas. A manera de conclusión se puede señalar que la incidencia de estas enfermedades está inversamente relacionada con los niveles de la variabilidad genética en las poblaciones, variabilidad que depende de eventos de colonización, recolonización y migración, así como de convenciones sociales como el racismo, la estratificación social y la segregación.

Human populations follow the same evolutionary principles as other organisms, although mixed with social and cultural elements, which can result in a high prevalence of certain diseases within specific ethnic groups. In this work, the Hardy-Weinberg principle is analyzed from a medical, social and biological viewpoint to understand the evolutionary processes of autosomal recessive diseases. It can be concluded that the incidence of these diseases is inversely related to the levels of genetic variability within populations, which depends on colonization, recolonization and migration events, as well as on social conventions such as racism, social stratification and segregation.