Examinando por Autor "Ramos Castañeda, José"

Mostrando 1 - 7 de 7
  • Publicación
    Acceso abierto
    Analysis of spatial mobility in subjects from a dengue endemic urban locality in Morelos State, Mexico
    (2017-02-22) Martínez Vega, Ruth Aralí; Santos Luna, René; Román Pérez, Susana; Herrera Valdez, Marco Arieli; Kuri Morales, Ángel Fernando; Adams, Ben; Kuri Morales, Pablo Antonio; López Cervantes, Malaquías; Ramos Castañeda, José; Falcón Lezama, Jorge Abelardo
    Mathematical models and field data suggest that human mobility is an important driver for Dengue virus transmission. Nonetheless little is known on this matter due the lack of instruments for precise mobility quantification and study design difficulties. Materials and methods We carried out a cohort-nested, case-control study with 126 individuals (42 cases, 42 intradomestic controls and 42 population controls) with the goal of describing human mobility patterns of recently Dengue virus-infected subjects, and comparing them with those of non-infected subjects living in an urban endemic locality. Mobility was quantified using a GPS-data logger registering waypoints at 60-second intervals for a minimum of 15 natural days. Results Although absolute displacement was highly biased towards the intradomestic and peridomestic areas, occasional displacements exceeding a 100-Km radius from the center of the studied locality were recorded for all three study groups and individual displacements were recorded traveling across six states from central Mexico. Additionally, cases had a larger number of visits out of the municipality´s administrative limits when compared to intradomestic controls (cases: 10.4 versus intradomestic controls: 2.9, p = 0.0282). We were able to identify extradomestic places within and out of the locality that were independently visited by apparently non-related infected subjects, consistent with houses, working and leisure places. Conclusions Results of this study show that human mobility in a small urban setting exceeded that considered by local health authority’s administrative limits, and was different between recently infected and non-infected subjects living in the same household. These observations provide important insights about the role that human mobility may have in Dengue virus transmission and persistence across endemic geographic areas that need to be taken into account when planning preventive and control measures. Finally, these results are a valuable reference when setting the parameters for future mathematical modeling studies.
  • Publicación
    Acceso abierto
    Antiviral effect of compounds derived from the seeds of Mammea americana and Tabernaemontana cymosa on Dengue and Chikungunya virus infections
    (2017-01-09) Martínez Vega, Ruth Aralí; Barreto Dos Santos, Flavia; Galvão de Araujo, Josélio Maria; Joint, Graham; Sarti, Elsa; Ramos Castañeda, José
    Dengue, the predominant arthropod-borne viral disease affecting humans, is caused by one of four distinct serotypes (DENV-1, -2, -3 or -4). A literature analysis and review was undertaken to describe the molecular epidemiological trends in dengue disease and the knowledge generated in specific molecular topics in Latin America, including the Caribbean islands, from 2000 to 2013 in the context of regional trends in order to identify gaps in molecular epidemiological knowledge and future research needs. Searches of literature published between 1 January 2000 and 30 November 2013 were conducted using specific search strategies for each electronic database that was reviewed. A total of 396 relevant citations were identified, 57 of which fulfilled the inclusion criteria. All four dengue virus serotypes were present and co-circulated in many countries over the review period (with the predominance of individual serotypes varying by country and year). The number of countries in which more than one serotype circulated steadily increased during the period under review. Molecular epidemiology data were found for Argentina, Bolivia, Brazil, the Caribbean region, Colombia, Ecuador, Mexico and Central America, Paraguay, Peru and Venezuela. Distinct lineages with different dynamics were found in each country, with co-existence, extinction and replacement of lineages occurring over the review period. Despite some gaps in the literature limiting the possibility for comparison, our review has described the molecular epidemiological trends of dengue infection. However, several gaps in molecular epidemiological information across Latin America and the Caribbean were identified that provide avenues for future research; in particular, sequence determination of the dengue virus genome is important for more precise phylogenetic classification and correlation with clinical outcome and disease severity.
  • Publicación
    Acceso abierto
    Dengue in Latin America : Systematic review of molecular epidemiological trends
    (2017-01-09) Ramos Castañeda, José; Barreto Dos Santos, Flavia; Martínez Vega, Ruth Aralí; Galvão de Araujo, Josélio Maria; Joint, Graham; Sarti, Elsa
    Dengue, the predominant arthropod-borne viral disease affecting humans, is caused by one of four distinct serotypes (DENV-1, -2, -3 or -4). A literature analysis and review was undertaken to describe the molecular epidemiological trends in dengue disease and the knowledge generated in specific molecular topics in Latin America, including the Caribbean islands, from 2000 to 2013 in the context of regional trends in order to identify gaps in molecular epidemiological knowledge and future research needs. Searches of literature published between 1 January 2000 and 30 November 2013 were conducted using specific search strategies for each electronic database that was reviewed. A total of 396 relevant citations were identified, 57 of which fulfilled the inclusion criteria. All four dengue virus serotypes were present and co-circulated in many countries over the review period (with the predominance of individual serotypes varying by country and year). The number of countries in which more than one serotype circulated steadily increased during the period under review. Molecular epidemiology data were found for Argentina, Bolivia, Brazil, the Caribbean region, Colombia, Ecuador, Mexico and Central America, Paraguay, Peru and Venezuela. Distinct lineages with different dynamics were found in each country, with co-existence, extinction and replacement of lineages occurring over the review period. Despite some gaps in the literature limiting the possibility for comparison, our review has described the molecular epidemiological trends of dengue infection. However, several gaps in molecular epidemiological information across Latin America and the Caribbean were identified that provide avenues for future research; in particular, sequence determination of the dengue virus genome is important for more precise phylogenetic classification and correlation with clinical outcome and disease severity.
  • Publicación
    Acceso abierto
    Dinámica Espaciotemporal de la Transmisión del Virus Dengue en Poblaciones Endémicas Mexicanas durante 2014 – 2016
    (2020-08-31) Tapias Rivera, Johanna; Martínez Vega, Ruth Aralí; Ramos Castañeda, José; Amaya Larios, Irma-Yvonne
    Tepalcingo y Axochiapan son localidades mexicanas del estado de Morelos, endémicas para dengue, allí convergen condiciones ambientales, biológicas y sociodemográficas para su persistencia. Conocer el comportamiento y la distribución de la infección por virus Dengue (DENV) permite detectar patrones espaciales y conglomerados de infecciones, áreas de alto riesgo de transmisión y reforzar actividades de vigilancia y control. El objetivo fue describir la dinámica espaciotemporal de la transmisión de DENV en las localidades de Tepalcingo y Axochiapan (México), durante 2014 – 2016. Se realizó análisis secundario de información recolectada en un estudio de cohorte prospectiva en dos localidades del estado de Morelos, incluyó sujetos evaluados cada seis meses con entrevista y toma de muestra de sangre para diagnóstico de infección reciente por DENV (ELISA IgM e IgG de captura). Se realizaron mapas de distribución espacial usando el software Arcgis10.5®, se estableció análisis de asociación utilizando STATA 15.1®. Se evaluaron en promedio 505 personas en cada seguimiento, identificando 175 infecciones por DENV. Los mapas de distribución espacial y agrupación en las localidades, muestran conglomerados de infección reciente por DENV en las colonias Guadalupe y San Francisco pertenecientes a Tepalcingo, y Del Carmen y El Progreso de Axochiapan, esta concentración de sujetos, demuestra la naturaleza focal de la transmisión de DENV. Respecto al análisis del riesgo de pertenecer a un conglomerado de transmisión, las actividades de control en las viviendas, de formas adultas como de inmaduras del vector, la presencia de pupas en las viviendas y el mantenimiento moderadamente ordenado del patio/jardín se asociaron a pertenecer la vivienda a conglomerados de transmisión de DENV. Conocer características de la población en riesgo de infección por DENV, detectar patrones espaciales, identificando conglomerados de infecciones permite focalizar medidas de control en áreas de mayor transmisión de DENV en vecindarios.
  • Publicación
    Acceso abierto
    Factores asociados a la infestación de las viviendas por Aedes spp. En dos localidades mexicanas con transmisión endémica de dengue
    (Bucaramanga : Universidad de Santander, 2019, 2019-03-22) Monroy Díaz, Ángela L.; Martínez Vega, Ruth Aralí; Ramos Castañeda, José
    El dengue es una de las principales Enfermedades Transmitidas por Vectores (ETV) y es un problema de salud pública a nivel mundial debido a su morbilidad y mortalidad. En México, es de alta endemia a pesar de las múltiples acciones de control utilizadas, lo cual fomenta el desarrollo de investigaciones que guíen a un control vectorial exitoso. El objetivo de este trabajo fue determinar los factores asociados a la infestación de la vivienda por Aedes spp. en dos localidades mexicanas. Materiales y métodos: Se realizó un análisis secundario de un estudio de cohorte con una encuesta de los factores entomológicos y sociodemográficos a una persona mayor de edad que vive en la casa y la inspección del patio y jardín correspondientes. La encuesta se aplicó cinco veces cada seis meses. Se determinaron índices Aedicos, además se evaluó la relación entre la infestación y las variables independientes mediante un análisis multinivel determinando los OR mediante una regresión logística binomial. Resultados El índice de Breteau mas alto fue 32, obtenido durante la primera evaluación además el índice de casa presentó un 29.3% en la última evaluación. En cuanto a las condiciones de la vivienda, se observó que la mayoría de los desagües estaban conectados a la red pública (Hasta 93.2%), los contenedores con los porcentajes más altos de infestación eran los tambos (Barriles de Agua) y el lavadero de ropa o pila con valores entre 20 y 55%. Los factores asociados con la infestación por Aedes fueron, el mantenimiento de la casa, el patio y el jardín, así como la cantidad de sombra en el patio. Conclusiones: Los resultados obtenidos muestran que, a pesar de las actividades antivectoriales, el objetivo de reducir la proliferación de Aedes no se ha alcanzado completamente.
  • Publicación
    Acceso abierto
    Peridomestic Infection as a Determining Factor of Dengue Transmission
    (2015-12-15) Martínez Vega, Ruth Aralí; Danis Lozano, Rogelio; Díaz Quijano, Fredi Alexander; Velasco Hernández, Jorge; Santos Luna, René; Román Pérez, Susana; Kuri Morales, Pablo Antonio; Ramos Castañeda, José
    Background The study of endemic dengue transmission is essential for proposing alternatives to impact its burden. The traditional paradigm establishes that transmission starts around cases, but there are few studies that determine the risk. Methods To assess the association between the peridomestic dengue infection and the exposure to a dengue index case (IC), a cohort was carried out in two Mexican endemic communities. People cohabitating with IC or living within a 50-meter radius (exposed cohort) and subjects of areas with no ICs in a 200-meter radius (unexposed cohort) were included. Results Exposure was associated with DENV infection in cohabitants (PRa 3.55; 95%CI 2.37–5.31) or neighbors (PRa 1.82; 95%CI 1.29–2.58). Age, location, toilets with no direct water discharge, families with children younger than 5 and the House Index, were associated with infection. Families with older than 13 were associated with a decreased frequency. After a month since the IC fever onset, the infection incidence was not influenced by exposure to an IC or vector density; it was influenced by the local seasonal behavior of dengue and the age. Additionally, we found asymptomatic infections accounted for 60% and a greater age was a protective factor for the presence of symptoms (RR 0.98; 95%CI 0.97–0.99). Conclusion The evidence suggests that dengue endemic transmission in these locations is initially peridomestic, around an infected subject who may be asymptomatic due to demographic structure and endemicity, and it is influenced by other characteristics of the individual, the neighborhood and the location. Once the transmission chain has been established, dengue spreads in the community probably by the adults who, despite being the group with lower infection frequency, mostly suffer asymptomatic infections and have higher mobility. This scenario complicates the opportunity and the effectiveness of control programs and highlights the need to apply multiple measures for dengue control.
  • Publicación
    Acceso abierto
    A prospective cohort study to assess seroprevalence, incidence, knowledge, attitudes and practices, willingness to pay for vaccine and related risk factors in dengue in a high incidence setting
    (2016-10-25) Martínez Vega, Ruth Aralí; Rodríguez Morales, Alfonso J.; Bracho Churio, Yalil Tomás; Castro Salas, Mirley Enith; Galvis Ovallos, Fredy; Díaz Quijano, Ronald Giovanny; Luna González, María Lucrecia; Castellanos, Jaime E.; Ramos Castañeda, José; Díaz Quijano, Fredi Alexander
    Background: Dengue is one of the most important vector-borne diseases in the world, causing significant morbidity and economic impact. In Colombia, dengue is a major public health problem. Departments of La Guajira, Cesar and Magdalena are dengue endemic areas. The objective of this research is to determine the seroprevalence and the incidence of dengue virus infection in the participating municipalities from these Departments, and also establish the association between individual and housing factors and vector indices with seroprevalence and incidence. We will also assess knowledge, attitudes and practices, and willingness-to-pay for dengue vaccine. Methods: A cohort study will be assembled with a clustered multistage sampling in 11 endemic municipalities. Approximately 1000 homes will be visited to enroll people older than one year who living in these areas, who will be followed for 1 year. Dengue virus infections will be evaluated using IgG indirect ELISA and IgM and IgG capture ELISA. Additionally, vector indices will be measured, and adult mosquitoes will be captured with aspirators. Ovitraps will be used for continuous estimation of vector density. Discussion: This research will generate necessary knowledge to design and implement strategies with a multidimensional approach that reduce dengue morbidity and mortality in La Guajira and other departments from Colombian Caribbean.