Deciphering the introduction and transmission of SARS-CoV-2 in the Colombian Amazon Basin

La pandemia del SARS-CoV-2 ha obligado a las autoridades sanitarias de todo el mundo a tomar importantes decisiones para reducir su propagación. La epidemiología genómica se ha convertido en una herramienta valiosa para comprender las introducciones y la propagación del virus en una ubicación geográfica específica.The SARS-CoV-2 pandemic has forced health authorities across the world to take important decisions to curtail its spread. Genomic epidemiology has emerged as a valuable tool to understand introductions and spread of the virus in a specific geographic location

Spatio-temporal dynamics of Plasmodium falciparum transmission within a spatial unit on the Colombian Pacific Coast

Funder: Newton-Caldas Fund Institutional Links, British Council, award G1854Funder: Newton-Caldas Fund Institutional Links, British Council, award G1854; Faculty of Medicine, Universidad Nacional de Colombia, awards HERMES 35988, 32309Abstract: As malaria control programmes concentrate their efforts towards malaria elimination a better understanding of malaria transmission patterns at fine spatial resolution units becomes necessary. Defining spatial units that consider transmission heterogeneity, human movement and migration will help to set up achievable malaria elimination milestones and guide the creation of efficient operational administrative control units. Using a combination of genetic and epidemiological data we defined a malaria transmission unit as the area contributing 95% of malaria cases diagnosed at the catchment facility located in the town of Guapi in the South Pacific Coast of Colombia. We provide data showing that P. falciparum malaria transmission is heterogeneous in time and space and analysed, using topological data analysis, the spatial connectivity, at the micro epidemiological level, between parasite populations circulating within the unit. To illustrate the necessity to evaluate the efficacy of malaria control measures within the transmission unit in order to increase the efficiency of the malaria control effort, we provide information on the size of the asymptomatic reservoir, the nature of parasite genotypes associated with drug resistance as well as the frequency of the Pfhrp2/3 deletion associated with false negatives when using Rapid Diagnostic Tests

Lanzamiento del Concurso : ¡Me la juego por Bogotá!

Lanzamiento del Concurso: ¡Me la juego por Bogotá! Dr. Alejandro Feged, profesor del programa de Gestión y Desarrollo Urbanos Ideas para la ciudad: Bogotá y sus protagonistas es un espacio organizado por la Facultad de Ciencia Política, Gobierno y Relaciones Internacionales que busca visibilizar iniciativas independientes que han transformado de diferentes maneras la calidad de vida de los bogotanos. Los asistentes tendrán la oportunidad de conocer diversos protagonistas y sus emprendimientos para mejorar nuestra ciudad

Ethnography of a parasite: A quantitative ethnographic observation of forest malaria in the Amazon basin

Aims: Malaria in the Amazon basin is persistently more prevalent among low density populations (1–4 people/km2). Describing malaria transmission in small populations, such as ethnic minorities in the Amazon basin, living in reserves in groups that amount to 110–450 individuals, is fundamental for the implementation of adequate interventions. Here, we examine malaria transmission in a context of high prevalence in a small population of Nükak ethnicity (ethnic group n = 400 ? 650 individuals, study group, n=108 individuals) living in the peri-urban area of a city with 35,000 inhabitants in the Amazon basin. Methods: Using methods from behavioral ecology, we conducted a quantitative ethnography and collected data to inform of individual behavioral profiles. Individual malarial infection reports were available from the local public health offices, so each behavioral profile was associated with an epidemic profile for the past 5 years. Results: Our research shows that, in-line with current opinion, malaria among the Nükak is not associated with an occupational hazard risk and follows a holoendemic pattern, where children are most susceptible to the parasite. Parasite loads of malarial infection among the Nükak persist at much higher rates than in any other neighboring ethnicity, which indicates an association between high incidence rates and endemicity. Conclusions: We hypothesize that malarial infection in the forest follows a pattern where the parasite persists in pockets of holoendemicity, and occupational hazard risk for individuals outside those pockets is associated with behaviors that take place in the proximity of the pockets of endemicity. © Author(s) 2018

Ethnography of a parasite: A quantitative ethnographic observation of forest malaria in the Amazon basin

Aims: Malaria in the Amazon basin is persistently more prevalent among low density populations (1–4 people/km2). Describing malaria transmission in small populations, such as ethnic minorities in the Amazon basin, living in reserves in groups that amount to 110–450 individuals, is fundamental for the implementation of adequate interventions. Here, we examine malaria transmission in a context of high prevalence in a small population of Nükak ethnicity (ethnic group n = 400 ? 650 individuals, study group, n=108 individuals) living in the peri-urban area of a city with 35,000 inhabitants in the Amazon basin. Methods: Using methods from behavioral ecology, we conducted a quantitative ethnography and collected data to inform of individual behavioral profiles. Individual malarial infection reports were available from the local public health offices, so each behavioral profile was associated with an epidemic profile for the past 5 years. Results: Our research shows that, in-line with current opinion, malaria among the Nükak is not associated with an occupational hazard risk and follows a holoendemic pattern, where children are most susceptible to the parasite. Parasite loads of malarial infection among the Nükak persist at much higher rates than in any other neighboring ethnicity, which indicates an association between high incidence rates and endemicity. Conclusions: We hypothesize that malarial infection in the forest follows a pattern where the parasite persists in pockets of holoendemicity, and occupational hazard risk for individuals outside those pockets is associated with behaviors that take place in the proximity of the pockets of endemicity. © Author(s) 2018

Demographic and epidemic transitions in peri-urban areas of Colombia: a multilevel study of malaria in the Amazonian city of San Jose del Guaviare

Migration to urban centres is among the most important forces in contemporary urban studies. In this paper, we study how the demography and epidemic profile of a community are altered when they transition from living in nomadic conditions in a forested environment to a peri-urban settlement in a city of the Amazon basin. We analyse demographic and epidemic data with a multilevel model to understand individual and community-level effects in terms of the risk of malarial infection. We show that malaria becomes endemic when the population settles in the peri-urban area of the city. We also show that the reproductive rate of women in the group increases as they become sedentary, and that while individual fertility rates have no effect on risk of contracting malaria, population-level fertility rates are associated with malaria endemicity

Malaria intensity in Colombia by regions and populations

Determining the distribution of disease prevalence among heterogeneous populations at the national scale is fundamental for epidemiology and public health. Here, we use a combination of methods (spatial scan statistic, topological data analysis and epidemic profile) to study measurable differences in malaria intensity by regions and populations of Colombia. This study explores three main questions: What are the regions of Colombia where malaria is epidemic? What are the regions and populations in Colombia where malaria is endemic? What associations exist between epidemic outbreaks between regions in Colombia? Plasmodium falciparum is most prevalent in the Pacific Coast, some regions of the Amazon Basin, and some regions of the Magdalena Basin. Plasmodium vivax is the most prevalent parasite in Colombia, particularly in the Northern Amazon Basin, the Caribbean, and municipalities of Sucre, Antioquia and Cordoba. We find an acute peak of malarial infection at 25 years of age. Indigenous and Afrocolombian populations experience endemic malaria (with household transmission). We find that Plasmodium vivax decreased in the most important hotspots, often with moderate urbanization rate, and was re-introduced to locations with moderate but sustained deforestation. Infection by Plasmodium falciparum, on the other hand, steadily increased in incidence in locations where it was introduced in the 2009-2010 generalized epidemic. Our findings suggest that Colombia is entering an unstable transmission state, where rapid decreases in one location of the country are interconnected with rapid increases in other parts of the country. © 2018 Feged-Rivadeneira et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Scaling dynamics of human diseases and urbanization in Colombia

Colombia has one of the largest numbers of internally displaced populations in the world and recently entered a period of post-conflict. These socio-political processes and trends have increased the migration of people towards cities and accordingly are affecting the distribution and occurrence of tropical diseases in its urban and peri-urban areas. Studies have suggested that many human phenomena such as urbanization scale according to the size of human populations regardless of cultural context. But other studies show that health epidemics such as malarial and human immunodeficiency virus infections, follow a scale-free distribution in terms of population size and density. We explore these relationships and dynamics in a tropical context using statistical analyses and available geospatial data to identify the scale dynamics between urbanization processes and disease transmission in Colombia. We found that rural populations and certain disease dynamics were described by power-laws that are frequently mentioned in urbanization studies. However, we found that malaria presented higher intensity of infection in human settlements of less than 50,000 individuals, particularly for ethnic indigenous populations. Results indicate that epidemics and urbanization dynamics do indeed follow scales in Colombia; findings that differ from previous epidemiological studies such as those for malarial infection. Additionally, we identified trends showing that malarial infections become endemic in peri-urban areas. Targeting such peri-urban locations and certain demographic groups are key for managing public health issues in the urbanizing tropics

Evaluating the role of spatial landscape literacy in public participation processes and opinions on environmental issues and ecosystem services

Se sabe poco sobre cómo influye la alfabetización espacial en la elaboración de mapas y la toma de decisiones relacionadas con la gestión medioambiental y los servicios ecosistémicos. Evaluamos el papel de la alfabetización espacial del paisaje en la gestión ambiental participativa y las evaluaciones de los servicios ecosistémicos en la Bogotá periurbana, Colombia. La alfabetización paisajística espacial se evaluó poniendo a prueba la capacidad de las partes interesadas para localizar paisajes y puntos de referencia específicos. A continuación, se evaluó si las opiniones sobre las decisiones medioambientales y los servicios ecosistémicos guardaban una relación significativa con la alfabetización paisajística. Se utilizó un instrumento en línea para recoger las características socioeconómicas de 2.397 encuestados, sus conocimientos sobre el paisaje espacial, sus percepciones de los servicios ecosistémicos y sus opiniones sobre cuestiones medioambientales relevantes. Evaluamos y medimos la SL autopercibida de los encuestados y su capacidad para localizar cuatro paisajes en un mapa integrado en línea. La precisión posicional se calculó utilizando un índice de alfabetización espacial del paisaje (SLI). A continuación, se comprobaron los efectos de los datos sociodemográficos en el SLI, se modeló la relación entre los datos sociodemográficos y la SL, y se comprobó la relación entre la SL de los encuestados y sus opiniones sobre cuestiones medioambientales relevantes y servicios ecosistémicos. Descubrimos que alrededor del 75% de los encuestados localizaron correctamente 2 de los 4 paisajes. Las variables sociodemográficas tampoco predijeron bien el modelo SLI. Sin embargo, encontramos relaciones significativas entre el SLI y las opiniones relativas al medio ambiente. No se encontró ninguna relación entre los niveles de participación activa de los encuestados en la gobernanza local y el SLI. En general, la SL se vio poco afectada por los niveles educativos. Lo ideal sería que los procesos participativos que utilizan mapas midieran la LS y no asumieran a priori que los participantes tienen conocimientos espaciales. Es necesario seguir investigando para evaluar cómo las tecnologías espaciales y la comprensión de los valores de las partes interesadas hacia el medio ambiente pueden democratizar la toma de decisiones participativa.Little is known about how spatial literacy influences mapping and decision-making related to environmental management and ecosystem services. We assessed the role of spatial landscape literacy in participatory environmental management and ecosystem service assessments in peri-urban Bogota, Colombia. Spatial landscape literacy (SL) was evaluated by testing stakeholder’s ability to locate specific landscapes and landmarks. We then assessed if opinions on environmental decisions and ecosystem services were significantly related to SL. We used an online instrument to capture 2,397 respondent’s socioeconomic characteristics, SL, ecosystem service perceptions, and opinions concerning relevant environmental issues. We evaluated and measured respondents’ self-perceived SL and ability to locate four landscapes in an integrated online map. Positional accuracy was calculated using a Spatial Landscape Literacy Index (SLI). We then tested for effects of socio-demographics on SLI, modeled the relationship between socio-demographics and SL, and tested the relationship between respondents’ SL and their opinions on relevant environmental issues and ecosystem services. We found that about 75% of the respondents correctly located 2 of the 4 landscapes. The SLI model was also poorly predicted by socio-demographic variables. However, we found significant relationships between SLI and opinions concerning the environment. No relationship was found between respondents’ levels of active participation in local governance and SLI. Overall, SL was little affected by education levels. Participatory processes using maps should ideally measure SL and not assume a priori that participants are spatially literate. Further research is needed to evaluate how spatial technologies and understanding stakeholder’s values towards the environment can democratize participatory-based decision-making

Trees and Crime in Bogota, Colombia: Is the link an ecosystem disservice or service?

There is a perception that increased forest cover and density in urban contexts is associated with increased criminality. But, this complex relationship between urban vegetation, crime, ecosystem services (ES) and disservices (ED), has been little studied in low and middle income countries. This study's aim was to statistically determine if specific structural and socioeconomic characteristics of urban treescapes were related to crime occurrence, considered an ED, in a major Latin American city. We used spatial and statistical analyses of a public tree inventory, homicide occurrence, and available geospatial data to analyze if urban treescape, demographic, and socioeconomic variables were related to the incidence of homicides in Neotropical Bogota, Colombia. First, a generalized linear model indicated that fewer homicides occurred in public treescapes with taller trees and higher tree density. In contrast, the amount of overall green space and average tree basal area were not significant predictors of homicide occurrence. Second, a geographically weighted regression model indicated that the inclusion of tree basal area rendered tree height insignificant, and that higher basal areas were associated with fewer homicides. Thus, both models indicated that increased tree density and size were actually associated with lower homicide occurrences. The amount of public green areas was however, not significantly related to homicide occurrence. Results indicate that in general, Bogota´s treescapes provided overall net ES as opposed to ED in terms of crime. Findings could be used to develop land use policies and management practices that increase the overall provision and demand for ES from urban forests. © 2018 Elsevier Lt