Examinando por Autor "Gutiérrez, Juan David"

Mostrando 1 - 8 de 8
  • Publicación
    Acceso abierto
    Comparing the identification of sites with high risk of landslides using isohyets of precipitation vs alterations of rainfall by La Niña in Santander Colombia
    (2015) Gutiérrez, Juan David
    Extreme meteorological events associated with climate change are a real issue and have important impact over the economy of infrastructure sector, including highways, hydrocarbon transport by pipelines, mines, etc., because saturation of soils by water can produce landslides and it could produce the fracture of pipelines or other kind of tangible assets. For example, an assessment of historical geotechnical failures in Ecopetrol (Colombian Oil Company) vs. extreme meteorological events shows that during La Niña (extreme rainfall period) geotechnical failures are three times greater. This work shows a method to identify places of risk by extreme meteorological events, mainly La Niña phenomenon, with focus in most probably alteration of rainfall. Our results illustrate the hot spots where there is a high probability of slight excess (120–160% of average rainfall) and high excess (>160%) of average rainfall. The results were intersected in a GIS with pipelines and mass movement risk maps to identify the places of high risk along Santander region.
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    Acceso abierto
    Effects of meteorological factors on human leptospirosis in Colombia
    (2020-10-10) Gutiérrez, Juan David; GAIA
    Leptospirosis is a disease usually acquired by humans through water contaminated with the urine of rodents that comes into direct contact with the cutaneous lesions, eyes, or mucous membranes. The disease has an important environmental component associated with climatic conditions and natural disasters, such as floods. We analyzed the relationship between rainfall and temperature and the incidence of leptospirosis in the top 30 municipalities with the highest numbers of cases of the disease in the period of 2007 to 2016. It was an ecological study of the time series of cases of leptospirosis, rainfall, and temperature with lags of 0, 1, 2, 3, and 4 weeks. A multilevel negative binomial regression model was implemented to evaluate the relationship between leptospirosis and both meteorological factors. In the 30 evaluated municipalities during the study period, a total of 5136 cases of leptospirosis were reported. According to the implemented statistical model, there was a positive association between the incidence of leptospirosis and rainfall with a lag of 1 week and a negative association with temperature with a lag of 4 weeks. Our results show the importance of short-term lags in rainfall and temperature for the occurrence of new cases of leptospirosis in Colombia.
  • Publicación
    Acceso abierto
    Environmental and socio-economic determinants associated with the occurrence of cutaneous leishmaniasis in the northeast of Colombia
    (2017-12) Gutiérrez, Juan David; Martínez Vega, Ruth Aralí; Ramoni Perazzi, Josefa; Díaz Quijano, Fredi Alexander; Gutiérrez, Reinaldo; Ruiz, Freddy J; Botello, Hector A.; Gil, María; González, Juan; Palencia, Mario
    Background: Cutaneous leishmaniasis (CL) is a vector-borne disease that is widely distributed in most tropical regions. Colombia has experienced an important increase in its incidence during the last decade. There are CL transmission foci in the Colombian departments of Santander and Norte de Santander. Objectives: To identify environmental and socio-economic variables associated with CL incidence in the municipalities of the northeast of Colombia between 2007 and 2016. Methods: This was an ecological study of CL cases aggregated by municipality. The cases reported during the study period were analyzed with a negative binomial regression to obtain the adjusted incident rate ratio for environmental and socio-economic variables. Findings: During the study period, 10 924 cases of CL were reported, and 110 (86.6%) municipalities reported at least one CL case. The coverages of forest (aIRR 1.05, 95% CI 1.03–1.07), heterogeneous agricultural zones (aIRR 1.04, 95% CI 1.02–1.06) and permanent crops (aIRR 1.07, 95% CI 1.02–1.12) were associated with a higher incidence of CL. Conversely, urban functionality (aIRR 0.95, 95% CI 0.92–0.96), minimal-altitude above sea level (aIRR 0.84, 95% CI 0.79–0.90) and shrub coverage (aIRR 0.98, 95% CI 0.95–1.0) were negatively associated with the incidence of CL in the municipality. Main conclusions: Our results confirm the importance of environmental determinants, such as height above sea level, and coverage of forest, permanent crops and heterogeneous agricultural zones, for the occurrence of CL; these findings also suggest the importance of shrub coverage. Furthermore, urban functionality was a socio-economic determinant independently associated with CL incidence.
  • Publicación
    Acceso abierto
    Environmental and socioeconomic determinants of leptospirosis incidence in Colombia
    (2019-03-25) Gutiérrez, Juan David; Martínez Vega, Ruth Aralí; Botello, Hector A.; Ruiz Herrera, Freddy Jesús; Arenas López, Laura Carolina; Hernández Tellez, Karen Dayana
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    Acceso abierto
    Potential distribution of four vectors of American Cutaneous Leishmaniasis: The effect of El Niño and La Niña episodes from the perspective of the ecological niche
    (2021-10-01) Avila-Jimenez, Julian; Gutiérrez, Juan David; Altamiranda-Saavedra, Mariano; GAIA
    The potential distribution of four American Cutaneous Leishmaniasis vectors under average conditions during Neutral (in between episodes), El Niño, and La Niña episodes from 2000 to 2018 were constructed through ecological niche modeling. The potential distribution in El Niño and La Niña were compared with the Neutral distribution. The four vector species (Lutzomyia gomezi, Lutzomyia ovallesi, Lutzomyia panamensis, and Lutzomyia trapidoi) decreased the potential distribution with the occurrence of El Niño and La Niña episodes. During El Niño, the reduction was concentrated over the dry ecosystems, while with the occurrence of La Niña, the potential distribution decreased over most of the Neotropic, leaving areas of climatic suitability concentrated in the Andean and Amazon areas, along with some scattered patches. We found evidence that the occurrence of the climatic anomalies has an effect on the potential distribution of this vector species.
  • Publicación
    Acceso abierto
    Relación de la incidencia de leishmaniasis cutánea y mucosa, con las zonas de mayor alteración de la temperatura y la precipitación inducida por los fenómenos de el niño y la niña en Colombia
    (Bucaramanga : Universidad de Santander, 2018, 2018-04-09) Díaz Díaz, Rolando; Martínez Vega, Ruth Aralí; Gutiérrez, Juan David
    Leishmaniasis is a vector-borne disease caused by protozoan parasite, it is transmitted by Lutzomiya. It is considered as a neglected disease by WHO, millions of people are exposed to contract the disease. Colombia, presents meteorological variations, with some climatic phenomena such as El Niño and La Niña in some periods of time, which may be associated with an increase in the cases of mucosal leishmaniasis (LM) and cutaneous leishmaniasis (LC). Materials and methods: Ecological study of time series was carried out, from a secondary source of information. The objective was to determine the relationship between LM and LC incidences and the variation of temperature and the variation of precipitation, also and El Niño y La Niña during the period between 2007 and 2015. The information used was obtained from SIVIGILA, DANE and IDEAM. A multilevel Poisson regression was performed to calculate the incidence rate ratio (IRR). Results: The variation of precipitation with a delay of three months and La Niña with two months of delay were associated with the decrease in the incidence rate of LC (IRRa 0.97 CI95% 0.95 - 0.99; IRRa 0.80 CI95% 0.78 - 0.83) and El Niño was associated with an increase in the incidence rate (IRRa 1.27 CI95% 1.23-1.32). Additionally, the variation of temperature with a month of delay was associated to the decrease of the LM rate (IRR 0.8 CI95% 0.68 - 0.95); on the contrary, the variation of the precipitation with three months of delay, increased the LM rate (IRR 1.21 CI95% 1.03 - 1.42). Conclusions: This information could use to improve the ability for planning specific prevention and mitigation strategies, through the generation of early warnings using public availability information.
  • Publicación
    Acceso abierto
    Segment scale typology for colombian andean rivers
    (2017-04) Gutiérrez, Juan David; Ospina-Torres, Rodulfo; Álvarez, Juan Pablo; Riss, Wolfgang; Guarín Villamizar, Oscar Darío
    This paper presents a method for establishing segment scale typology for the Andean rivers of Colombia. The method incorporates physical and ecological aspects and combines inferences of structural stability and metabolic activity. The classification of river segments is based on the assignment of two non-dimensional descriptors. The first descriptor involves aspects related to structural stability of the channel, whereas the second descriptor includes factors that affect the metabolic activity of planktonic communities in the water column and biotic communities on the bed. Each descriptor can adopt values that are divided into two categories, high and low. Both descriptors are organized orthogonally. A bidimensional 2 × 2 matrix is created, where the x-axis represents the current structural stability of the channel and the y-axis represents the metabolic activity. A case study that combines a set of thematic layers using GIS is presented for the Cundinamarca region in Colombia. Most of the river segments (97%) in Cundinamarca correspond to type 2 or 4. We provide data from macroinvertebrate samples to compare the obtained types with the actual biological communities present in the region. This method, which can be useful for scientists, managers and water planners, compares similarities and differences between water body systems, compiles basic information in a brief and clear manner and locates monitoring and reference sites for bioassessment studies.
  • Publicación
    Acceso abierto
    Spatiotemporal dynamics of human leptospirosis and its relationship with rainfall anomalies in Colombia
    (2018-04-09) Gutiérrez, Juan David; Martínez Vega, Ruth Aralí
    Background In Colombia, human leptospirosis (HL) is a disease that has had a mandatory notification rule since 2007. Humans usually acquire the infection through water contaminated with animal urine that comes into direct contact with cutaneous lesions, eyes or mucous membranes. Objectives To analyze the spatiotemporal variability in the occurrence of HL cases in Colombia between 2007 and 2016, and its relation with the El Niño Southern Oscillation (ENSO) cycle and the consequent anomalies in rainfall in spatiotemporal clusters. Methods An ecological study of the HL cases, aggregated by municipality, and reported between 2007 and 2016, is presented. Findings During the period of study, 9928 cases of HL were reported, and 58.9% of the municipalities reported at least one case of leptospirosis. Six spatiotemporal clusters were identified—five were in the Andean region and one was in the Caribbean region. The assessment of the ENSO cycle and rainfall anomalies suggests the importance of La Niña episodes, and excess rainfall periods in the occurrence of cases of HL. Conclusions Our results demonstrate the importance of the ENSO cycle, rainfall periods and periods with excess rainfall in the occurrence of cases and outbreaks of HL in Colombia, and suggest the importance of the topography of valleys and flood zones as zones in which the risk of infection is elevated.