<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0120-4157</journal-id>
<journal-title><![CDATA[Biomédica]]></journal-title>
<abbrev-journal-title><![CDATA[Biomed.]]></abbrev-journal-title>
<issn>0120-4157</issn>
<publisher>
<publisher-name><![CDATA[Instituto Nacional de Salud]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-41572020000600166</article-id>
<article-id pub-id-type="doi">10.7705/biomedica.5802</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[SARS-CoV-2 y RT-PCR en pacientes asintomáticos: resultados de una cohorte de trabajadores del Aeropuerto Internacional El Dorado de Bogotá, 2020]]></article-title>
<article-title xml:lang="en"><![CDATA[SARS-CoV-2 and RT-PCR in asymptomatic patients: Results of a cohort of workers at El Dorado International Airport in Bogotá, 2020]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Malagón-Rojas]]></surname>
<given-names><![CDATA[Jeadran]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gómez-Rendón]]></surname>
<given-names><![CDATA[Claudia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Parra]]></surname>
<given-names><![CDATA[Eliana L.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Almentero]]></surname>
<given-names><![CDATA[Julia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Palma]]></surname>
<given-names><![CDATA[Ruth]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López]]></surname>
<given-names><![CDATA[Ronald]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Toloza-Pérez]]></surname>
<given-names><![CDATA[Yesith Guillermo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rubio]]></surname>
<given-names><![CDATA[Vivian]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Bedoya]]></surname>
<given-names><![CDATA[Juan Felipe]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López-Díaz]]></surname>
<given-names><![CDATA[Fernando]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Franco-Muñoz]]></surname>
<given-names><![CDATA[Carlos]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Reales-González]]></surname>
<given-names><![CDATA[Jhonnatan]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mercado]]></surname>
<given-names><![CDATA[Marcela]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad El Bosque  ]]></institution>
<addr-line><![CDATA[Bogotá D.C]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Instituto Nacional de Salud  ]]></institution>
<addr-line><![CDATA[Bogotá D.C]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>10</month>
<year>2020</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>10</month>
<year>2020</year>
</pub-date>
<volume>40</volume>
<fpage>166</fpage>
<lpage>172</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-41572020000600166&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-41572020000600166&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-41572020000600166&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Introducción. La pandemia de COVID-19 ha ocasionado cerca de 25 millones de casos en el mundo. Se ha descrito que los pacientes asintomáticos pueden ser fuentes de transmisión. Sin embargo, es difícil detectarlos y no es claro su papel en la dinámica de transmisión del virus, lo que obstaculiza la implementación de estrategias para la prevención.  Objetivo. Describir el comportamiento de la infección asintomática por SARS-CoV-2 en una cohorte de trabajadores del Aeropuerto Internacional El Dorado "Luis Carlos Galán Sarmiento" de Bogotá, Colombia.  Materiales y métodos. Se diseñó una cohorte prospectiva de trabajadores del Aeropuerto El Dorado. El seguimiento se inició en junio de 2020 con una encuesta a cada trabajador para caracterizar sus condiciones de salud y trabajo. Cada 21 días se tomó una muestra de hisopado nasofaríngeo para detectar la presencia del SARS-CoV-2 mediante reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR). Se analizó el comportamiento del umbral del ciclo (cycle threshold) de los genes ORFlab y N según el día de seguimiento.  Resultados. En los primeros tres seguimientos de la cohorte se encontró una incidencia de la infección por SARS-CoV-2 del 16,51 %. La proporción de contactos positivos fue del 14,08 %. La mediana del umbral del ciclo fue de 33,53.  Conclusión. Se determinaron las características de la infección asintomática por el SARS-CoV-2 en una cohorte de trabajadores. La detección de infectados asintomáticos sigue siendo un reto para los sistemas de vigilancia epidemiológica.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  Introduction: The 2019 coronavirus pandemic (COVID-19) has caused around 25 million cases worldwide. Asymptomatic patients have been described as potential sources of transmission. However, there are difficulties to detect them and to establish their role in the dynamics of virus transmission, which hinders the implementation of prevention strategies.  Objective: To describe the behavior of asymptomatic SARS-CoV-2 virus infection in a cohort of workers at the El Dorado "Luis Carlos Galán Sarmiento" International Airport in Bogotá, Colombia.  Materials and methods: A prospective cohort of 212 workers from the El Dorado airport was designed. The follow-up began in June, 2020. A survey was used to characterize health and work conditions. Every 21 day, a nasopharyngeal swab was taken to identify the presence of SARS-CoV-2 using RT-PCR. We analyzed the behavior of the cycle threshold (ORFlab and N genes) according to the day of follow-up.  Results: In the first three follow-ups of the cohort, we found an incidence of SARS-CoV-2 infection of 16.51%. The proportion of positive contacts was 14.08%. The median threshold for cycle threshold was 33.53.  Conclusion: We characterized the asymptomatic SARS-CoV-2 infection in a cohort of workers. The identification of asymptomatic infected persons continues to be a challenge for epidemiological surveillance systems.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[infecciones por coronavirus]]></kwd>
<kwd lng="es"><![CDATA[infecciones asintomáticas]]></kwd>
<kwd lng="es"><![CDATA[síndrome de dificultad respiratoria del adulto]]></kwd>
<kwd lng="es"><![CDATA[salud laboral]]></kwd>
<kwd lng="es"><![CDATA[reacción en cadena de la polimerasa de transcriptasa inversa]]></kwd>
<kwd lng="en"><![CDATA[Coronavirus infections]]></kwd>
<kwd lng="en"><![CDATA[asymptomatic infections]]></kwd>
<kwd lng="en"><![CDATA[respiratory distress syndrome, adult]]></kwd>
<kwd lng="en"><![CDATA[occupational health]]></kwd>
<kwd lng="en"><![CDATA[reverse transcriptase polymerase chain reaction]]></kwd>
</kwd-group>
</article-meta>
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