31 research outputs found

    Traveling with an invader: ectoparasitic mites of Hemidactylus frenatus (Squamata: Gekkonidae) in Colombia

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    Information about natural history of invasive species (such as parasitism) is a relevant issue in order to consider potential threats to native fauna. In this work we report two pterygosomatid mites for the first time in Colombia, Geckobia bataviensis and G. keegani, parasites of the invasive house gecko Hemidactylus frenatus. Although it has not been demonstrated that these mites may infest native gecko lizards, our study highlights the need to explore the prevalence of internal and external parasites in native and invasive geckos, to better evaluate the potential impact of invasive Hemidactylus lizards in Colombia.Asociación Herpetológica Argentin

    Traveling with an invader: ectoparasitic mites of Hemidactylus frenatus (Squamata: Gekkonidae) in Colombia

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    Information about natural history of invasive species (such as parasitism) is a relevant issue in order to consider potential threats to native fauna. In this work we report two pterygosomatid mites for the first time in Colombia, Geckobia bataviensis and G. keegani, parasites of the invasive house gecko Hemidactylus frenatus. Although it has not been demonstrated that these mites may infest native gecko lizards, our study highlights the need to explore the prevalence of internal and external parasites in native and invasive geckos, to better evaluate the potential impact of invasive Hemidactylus lizards in Colombia.Asociación Herpetológica Argentin

    Traveling with an invader: ectoparasitic mites of Hemidactylus frenatus (Squamata: Gekkonidae) in Colombia

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    Information about natural history of invasive species (such as parasitism) is a relevant issue in order to consider potential threats to native fauna. In this work we report two pterygosomatid mites for the first time in Colombia, Geckobia bataviensis and G. keegani, parasites of the invasive house gecko Hemidactylus frenatus. Although it has not been demonstrated that these mites may infest native gecko lizards, our study highlights the need to explore the prevalence of internal and external parasites in native and invasive geckos, to better evaluate the potential impact of invasive Hemidactylus lizards in Colombia.Asociación Herpetológica Argentin

    Diseño y validación analítica de una PCR duplex para la detección de Ehrlichia y Rickettsia en garrapatas

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    ABSTRACT: Ehrlichia and Rickettsia are two major rickettsial genera transmitted by ticks that affect a number of wild and domestic animal species and human populations around the world. Objective: To design and validate a duplex PCR for Ehrlichia and Rickettsia in ticks. Methods:Assay validation included testing for sensitivity,specificity, reproducibility, and robustness of the PCR. The groELand 23sr RNAgenes were used for Ehrlichia and Rickettsia, respectively. Results: The limit of detection was one hundred gene copies per 50 μLof reaction for Ehrlichia spp, and one gene copy of Rickettsia per 50 μL of reaction. In general, the primers of the test only amplified in silico those bacterial agents for which they were originally designed, with the exception of the primers for Rickettsia that also amplified Methylocystis sp. The test was reproducible (intermediate precision) 96.7% of the times for both agents. The test was robust enough to tolerate concentration changes of all reagents with the exception of Taq DNA polymerase. Conclusions: The validation results indicated that this PCR is useful for detection in both bacterial genera and it is a good candidate for diagnostic validation.RESUMEN: Ehrlichia spp. y Rickettsia spp.son dos de los principales géneros rickettsiales transmitidos por garrapatas que afectan a animales silvestres, domésticos y humanos alrededor del mundo. Objetivo: diseñar y validar una prueba PCR duplex para Ehrlichia y Rickettsia en garrapatas. Métodos: la validación de la prueba incluyó ensayos de sensibilidad, especificidad, reproducibilidad y robustez. En la PCR se usó groEL y ARNr 23S como genes blanco para Ehrlichia y Rickettsia, respectivamente. Resultados: el límite de detección fue de 100 copias del gen por 50 μL de reacción para Ehrlichia spp y una copia del gen de Rickettsia por 50 μLde reacción. En general, los cebadores de la prueba solo amplificaron in silico los agentes bacterianos para los cuales fueron originalmente diseñados, con la excepción de los cebadores de Rickettsia que también amplificaron Methylocystis sp. La prueba fue reproducible (precisión intermedia) en un 96.7% de las veces para ambos agentes. La prueba fue suficientemente robusta como para tolerar cambios de concentración de los diferentes reactivos, con excepción de la Taq DNA polimerasa. Conclusión: los resultados de validación indican que la PCR es útil para detectar ambos géneros bacterianos y podría usarse para validación diagnóstica

    Modelos potenciales de distribución geográfica y climática del complejo Amblyomma cajennense (Acari: Ixodidae), potencial vector de Rickettsia rickettsii en Colombia

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    Introduction: The species of the Amblyoma cajennense complex, potential vectors involved in the transmission of Rickettsia rickettsii in Central and South America, have a wide geographical distribution in the Neotropics. In Colombia, the knowledge about these species, their distribution, and many aspects of their ecology is still limited.Objective: To explore the ecology of A. cajennense complex in Colombia based on the study of its habitat selection, as well as the generation of potential geographic and climatic distribution models.Materials and methods: We used unique records of these ticks to study the selection patterns of the climatic habitat using the Ecological Niche Factor Analysis (ENFA), and we built distribution models using the MaxEnt and GARP algorithms.Results: The record of distributions showed that A. cajennense complex is present in all five natural regions of Colombia with 64.71% of the records found in the departments of Antioquia, Cundinamarca, and Huila. The analysis of their habitat selection showed that these ticks preferably select geographical areas (ENFA: 96.03%) according to the isothermality conditions and the precipitation of the driest quarter of the year. The potential distribution models indicated habitat suitability in 31 to 51% of the area of the country depending on the algorithm.Conclusions: The distribution of A. cajennense complex in Colombia is highly influenced by a climatebased habitat selection, a characteristic that favored the creation of distribution models. Field studies will allow the validation of the potential distribution models and further genetic studies will be required in the country to identify species within the complex and study their potential hybridization areas.Introducción. Las especies del complejo Amblyomma cajennense, potenciales vectores implicados en la transmisión de Rickettsia rickettsii en Centroamérica y Suramérica, presentan una amplia distribución geográfica en el neotrópico. En Colombia, todavía es incipiente el conocimiento sobre las especies de este complejo, su distribución y su ecología.Objetivo. Explorar la ecología del complejo A. cajennense en Colombia a partir del estudio de su selección de hábitat y la generación de modelos potenciales de distribución geográfica y climática.Materiales y métodos. Se utilizaron registros únicos de la presencia de estas garrapatas en el estudio de sus patrones de selección del hábitat, mediante el análisis factorial del nicho ecológico (Ecological Niche Factor Analysis, ENFA), y se construyeron modelos de distribución potencial con las metodologías MaxEnt y GARP.Resultados. El complejo A. cajennense se encontró en las cinco regiones naturales de Colombia, con 64,71 % de los registros procedentes de los departamentos de Antioquia, Cundinamarca y Huila. La selección del hábitat evidenció que estas garrapatas escogen preferentemente las áreas geográficas (ENFA: 96,03 %) según sus condiciones de índice de estabilidad térmica y de precipitación en el trimestre más seco del año. Los modelos de distribución potencial indicaron la idoneidad del hábitat en 31 a 51 % del área del país dependiendo del algoritmo empleado.Conclusiones. En Colombia, el complejo A. cajennense presenta una distribución muy influenciada por el comportamiento en la selección del hábitat climático, característica que facilitó la creación de modelos de distribución. En futuros estudios de campo, se podrían validar los modelos presentados; se requieren, además, otros estudios genéticos para la identificación de especies del complejo y el manejo de sus potenciales zonas de hibridación en el país

    Eco-epidemiological analysis of rickettsial seropositivity in rural areas of Colombia: A multilevel approach

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    ABSTARCT: Rickettsiosis is a re-emergent infectious disease without epidemiological surveillance in Colombia. This disease is generally undiagnosed and several deadly outbreaks have been reported in the country in the last decade. The aim of this study is to analyze the eco-epidemiological aspects of rickettsial seropositivity in rural areas of Colombia where outbreaks of the disease were previously reported. A cross-sectional study, which included 597 people living in 246 households from nine hamlets in two municipalities of Colombia, was conducted from November 2015 to January 2016. The survey was conducted to collect sociodemographic and household characteristics (exposure) data. Blood samples were collected to determine the rickettsial seropositivity in humans, horses and dogs (IFA, cut-off = 1/128). In addition, infections by rickettsiae were detected in ticks from humans and animals by real-time PCR targeting gltA and ompA genes. Data was analyzed by weighted multilevel clog-log regression model using three levels (person, household and hamlets) and rickettsial seropositivity in humans was the main outcome. Overall prevalence of rickettsial seropositivity in humans was 25.62% (95%CI 22.11-29.12). Age in years (PR = 1.01 95%CI 1.01-1.02) and male sex (PR = 1.65 95%CI 1.43-1.90) were risk markers for rickettsial seropositivity. Working outdoors (PR = 1.20 95%CI 1.02-1.41), deforestation and forest fragmentation for agriculture use (PR = 1.75 95%CI 1.51-2.02), opossum in peridomiciliary area (PR = 1.56 95%CI 1.37-1.79) and a high proportion of seropositive domestic animals in the home (PR20-40% vs 40% vs <20% = 3.14 95%CI 2.43-4.04) were associated with rickettsial seropositivity in humans. This study showed the presence of Rickettsia antibodies in human populations and domestic animals. In addition, different species of rickettsiae were detected in ticks collected from humans and animals. Our results highlighted the role of domestic animals as sentinels of rickettsial infection to identify areas at risk of transmission, and the importance of preventive measures aimed at curtailing deforestation and the fragmentation of forests as a way of reducing the risk of transmission of emergent and re-emergent pathogens

    Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950-2019 : a comprehensive demographic analysis for the Global Burden of Disease Study 2019

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    Background: Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019. Methods: 8078 country-years of vital registration and sample registration data, 938 surveys, 349 censuses, and 238 other sources were identified and used to estimate age-specific fertility. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate age-specific fertility rates for 5-year age groups between ages 15 and 49 years. With extensions to age groups 10–14 and 50–54 years, the total fertility rate (TFR) was then aggregated using the estimated age-specific fertility between ages 10 and 54 years. 7417 sources were used for under-5 mortality estimation and 7355 for adult mortality. ST-GPR was used to synthesise data sources after correction for known biases. Adult mortality was measured as the probability of death between ages 15 and 60 years based on vital registration, sample registration, and sibling histories, and was also estimated using ST-GPR. HIV-free life tables were then estimated using estimates of under-5 and adult mortality rates using a relational model life table system created for GBD, which closely tracks observed age-specific mortality rates from complete vital registration when available. Independent estimates of HIV-specific mortality generated by an epidemiological analysis of HIV prevalence surveys and antenatal clinic serosurveillance and other sources were incorporated into the estimates in countries with large epidemics. Annual and single-year age estimates of net migration and population for each country and territory were generated using a Bayesian hierarchical cohort component model that analysed estimated age-specific fertility and mortality rates along with 1250 censuses and 747 population registry years. We classified location-years into seven categories on the basis of the natural rate of increase in population (calculated by subtracting the crude death rate from the crude birth rate) and the net migration rate. We computed healthy life expectancy (HALE) using years lived with disability (YLDs) per capita, life tables, and standard demographic methods. Uncertainty was propagated throughout the demographic estimation process, including fertility, mortality, and population, with 1000 draw-level estimates produced for each metric. Findings: The global TFR decreased from 2·72 (95% uncertainty interval [UI] 2·66–2·79) in 2000 to 2·31 (2·17–2·46) in 2019. Global annual livebirths increased from 134·5 million (131·5–137·8) in 2000 to a peak of 139·6 million (133·0–146·9) in 2016. Global livebirths then declined to 135·3 million (127·2–144·1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2·1, which is considered a good approximation of replacement-level fertility. All countries in sub-Saharan Africa had TFRs above replacement level in 2019 and accounted for 27·1% (95% UI 26·4–27·8) of global livebirths. Global life expectancy at birth increased from 67·2 years (95% UI 66·8–67·6) in 2000 to 73·5 years (72·8–74·3) in 2019. The total number of deaths increased from 50·7 million (49·5–51·9) in 2000 to 56·5 million (53·7–59·2) in 2019. Under-5 deaths declined from 9·6 million (9·1–10·3) in 2000 to 5·0 million (4·3–6·0) in 2019. Global population increased by 25·7%, from 6·2 billion (6·0–6·3) in 2000 to 7·7 billion (7·5–8·0) in 2019. In 2019, 34 countries had negative natural rates of increase; in 17 of these, the population declined because immigration was not sufficient to counteract the negative rate of decline. Globally, HALE increased from 58·6 years (56·1–60·8) in 2000 to 63·5 years (60·8–66·1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019

    Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

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    Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

    Canis familiaris, UN NUEVO HOSPEDERO DE Ornithodoros (A.) puertoricensis FOX, 1947 (ACARI: IXODIDA) EN COLOMBIA

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    &lt;p&gt;&lt;span style="font-size: x-small; font-family: verdana;"&gt;&lt;span style="font-size: medium;"&gt;RESUMEN &lt;/span&gt;&lt;/span&gt;&lt;/p&gt; &lt;p&gt;&lt;span style="font-size: x-small; font-family: verdana;"&gt;&lt;span style="font-size: medium;"&gt;Las garrapatas revisten gran importancia en el campo biomédico por sus hábitos hematófagos y asociación con la transmisión de agentes patógenos a humanos y animales. El objetivo de esta investigación fue establecer las especies de garrapatas que parasitan perros en tres poblaciones del área rural del Caribe colombiano. Durante los meses de agosto y diciembre del año 2006 se realizó búsqueda activa de garrapatas sobre caninos domésticos de las localidades de El Campín, Sabanas del Potrero y Escobar Arriba, departamento de Sucre. Las garrapatas recolectadas fueron almacenadas en viales con etanol al 70% e identificadas empleando claves morfológicas de referencia para cada familia. Para la determinación de especie en la familia Argasidae se realizaron estimaciones morfométricas de estructuras externas. Se recolectaron 420 garrapatas a partir de 50 caninos infestados, de un total de 134 perros examinados, que corresponde a una tasa de infestación del 37,3%. Las garrapatas fueron identificadas como &lt;em&gt;Rhipicephalus sanguineus&lt;/em&gt;, &lt;em&gt;Rhipicephalus &lt;/em&gt;(&lt;em&gt;Boophilus&lt;/em&gt;) &lt;em&gt;microplus &lt;/em&gt;y &lt;em&gt;Amblyomma ovale &lt;/em&gt;pertenecientes a la familia Ixodidae, y &lt;em&gt;Ornithodoros &lt;/em&gt;(&lt;em&gt;Alectorobius&lt;/em&gt;) &lt;em&gt;puertoricensis &lt;/em&gt;de la familia Argasidae. La especie predominante fue &lt;em&gt;R. sanguineus &lt;/em&gt;(92,1%) en los estados de larva, ninfa y adulto, seguida por larvas de &lt;em&gt;O. puertoricensis&lt;/em&gt;, que fueron halladas en menor número sobre caninos de las tres localidades. Se registra, por primera vez en América, el parasitismo de &lt;em&gt;O. puertoricensis &lt;/em&gt;sobre caninos domésticos y se confirma su presencia en Colombia. &lt;/span&gt;&lt;/span&gt;&lt;/p&gt; &lt;p&gt;&lt;span style="font-size: x-small; font-family: verdana;"&gt;&lt;span style="font-size: medium;"&gt;Palabras clave: garrapatas, perros, &lt;em&gt;Ornithodoros puertoricensis&lt;/em&gt;, Ixodida, Colombia. &lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;span style="font-size: x-small; font-family: verdana;"&gt;&lt;span style="font-size: medium;"&gt; &lt;/span&gt;&lt;/span&gt;&lt;hr size="1" /&gt;&lt;p&gt;&lt;span style="font-size: x-small; font-family: verdana;"&gt;&lt;span style="font-size: medium;"&gt;ABSTRACT &lt;/span&gt;&lt;/span&gt;&lt;/p&gt; &lt;p&gt;&lt;span style="font-size: x-small; font-family: verdana;"&gt;&lt;span style="font-size: medium;"&gt;Ticks are very important from the biomedical point of view, by their hematophagic activity and their role in the transmission of pathogenic microorganisms to man and animals. The main goal of this work was to establish the tick species parasiting dogs in three rural localities of the Colombian Caribbean. From August to December 2006, an active search of ticks on dogs was carried out in the localities of El Campín, Sabanas del Potrero and Escobar Arriba, department of Sucre. The collected ticks were preserved into eppendorf tubes with 70% ethanol, and identified using standard morphological keys for each family. Argasid species were determined by measuring external morphological characters. Of 134 examined dogs in the three localities, 50 were found infested by ticks, representing a infestation rate of 37,3%. A total of 420 ticks were collected from dogs and identified as &lt;em&gt;Rhipicephalus sanguineus&lt;/em&gt;, &lt;em&gt;Rhipicephalus &lt;/em&gt;(&lt;em&gt;Boophilus&lt;/em&gt;) &lt;em&gt;microplus&lt;/em&gt;, and &lt;em&gt;Amblyomma ovale &lt;/em&gt;of the Ixodidae family, and &lt;em&gt;Ornithodoros puertoricensis &lt;/em&gt;of the Argasidae family. &lt;em&gt;R. sanguineus &lt;/em&gt;was the predominant species (92,1%) in the stages of larva, nymph and adult, following by &lt;em&gt;O. puertoricensis &lt;/em&gt;larvae recorded in low numbers in the three regions sampled. The tick &lt;em&gt;O. puertoricensis &lt;/em&gt;is recorded for the first time as ectoparasite of domestic dogs in America. Additionally, the presence of this tick species is confirmed in Colombia. &lt;/span&gt;&lt;/span&gt;&lt;/p&gt; &lt;p&gt;&lt;span style="font-size: x-small; font-family: verdana;"&gt;&lt;span style="font-size: medium;"&gt;Key words: Ticks, dogs, &lt;em&gt;Ornithodoros puertoricensis&lt;/em&gt;, Ixodida, Colombia &lt;/span&gt;&lt;/span&gt;&lt;/p&gt
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