<?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>0036-3634</journal-id>
<journal-title><![CDATA[Salud Pública de México]]></journal-title>
<abbrev-journal-title><![CDATA[Salud pública Méx]]></abbrev-journal-title>
<issn>0036-3634</issn>
<publisher>
<publisher-name><![CDATA[Instituto Nacional de Salud Pública]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0036-36342021000600803</article-id>
<article-id pub-id-type="doi">10.21149/12847</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Seroprevalencia de SARS-CoV-2 en niños y adolescentes mexicanos en edad escolar]]></article-title>
<article-title xml:lang="en"><![CDATA[Seroprevalence of SARS-CoV-2 in Mexican children and adolescents in primary and secondary education age]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Canto-Osorio]]></surname>
<given-names><![CDATA[Francisco]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Stern]]></surname>
<given-names><![CDATA[Dalia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Pérez-Ferrer]]></surname>
<given-names><![CDATA[Carolina]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Arias-de la Garza]]></surname>
<given-names><![CDATA[Eduardo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Danon]]></surname>
<given-names><![CDATA[Leon]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
<xref ref-type="aff" rid="A a"/>
<xref ref-type="aff" rid="A7 "/>
<xref ref-type="aff" rid="Af8"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Barrientos-Gutiérrez]]></surname>
<given-names><![CDATA[Tonatiuh]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Lajous]]></surname>
<given-names><![CDATA[Martín]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Instituto Nacional de Salud Pública Centro de Investigación en Salud Poblacional ]]></institution>
<addr-line><![CDATA[Cuernavaca Morelos]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Consejo Nacional de Ciencia y Tecnología  ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>México</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Instituto Nacional de Salud Pública Centro de Investigación en Nutrición y Salud ]]></institution>
<addr-line><![CDATA[Cuernavaca Morelos]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,Instituto Nacional de Pediatría Servicio de Infectología ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>México</country>
</aff>
<aff id="Af5">
<institution><![CDATA[,Joint Universities Pandemic and Epidemiological Research  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Reino Unido</country>
</aff>
<aff id="Af6">
<institution><![CDATA[,University of Bristol Population Health Sciences Bristol Medical School]]></institution>
<addr-line><![CDATA[Bristol ]]></addr-line>
<country>United Kingdom</country>
</aff>
<aff id="Af7">
<institution><![CDATA[,British Library The Alan Turing Institute ]]></institution>
<addr-line><![CDATA[Londres ]]></addr-line>
<country>Reino Unido</country>
</aff>
<aff id="Af8">
<institution><![CDATA[,University of Bristol Department of Engineering Mathematics ]]></institution>
<addr-line><![CDATA[Bristol ]]></addr-line>
<country>United Kingdom</country>
</aff>
<aff id="Af9">
<institution><![CDATA[,Harvard T.H. Chan School of Public Health Department of Global Health and Population ]]></institution>
<addr-line><![CDATA[Boston ]]></addr-line>
<country>Estados Unidos</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<volume>63</volume>
<numero>6</numero>
<fpage>803</fpage>
<lpage>806</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0036-36342021000600803&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0036-36342021000600803&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0036-36342021000600803&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen:  Objetivo:  Estimar la seroprevalencia de SARS-CoV-2 en población de edad escolar en México.  Material y métodos:  Se categorizaron a niños y adolescentes que participaron en la Encuesta Nacional de Salud y Nutrición 2020 sobre Covid-19 (Ensanut 2020 Covid-19) por edad escolar y nivel educativo. En participantes seropositivos, se identificó la proporción de infecciones asintomáticas. Se estimaron razones de prevalencia usando un modelo de regresión log-binomial.  Resultados:  La seroprevalencia en educación básica y media fue de 18.7% (IC95%: 14.9, 22.5) y 26.7% (IC95%: 22.1, 31.3), respectivamente. La infección asintomática fue más frecuente en educación básica (88.5% [IC95%: 80.5, 93.5]).  Conclusiones:  En población de educación básica la infección por SARS-CoV-2 es baja y usualmente asintomática.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract:  Objective:  To estimate the seroprevalence of SARS-CoV-2 in school aged children in Mexico.  Materials and methods:  We categorized children and adolescents who participated in the 2020 National Health and Nutrition Survey on Covid-19 according to school age and educational level. In seropositive participants, we identified the proportion of asymptomatic infections. We estimated prevalence ratios using a log-binomial regression model.  Results:  Seroprevalence of SARS-CoV-2 for primary and secondary education were 18.7% (95%IC: 14.9, 22.5) and 26.7% (95%IC: 22.1, 31.3), respectively. Asymptomatic infection was more frequent among primary school children (88.5% [95%IC: 80.5, 93.5]).  Conclusions:  In primary schoolchildren seroprevalence for SARS-CoV-2 was low and infections were usually asymptomatic.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[seroprevalencia]]></kwd>
<kwd lng="es"><![CDATA[SARS-CoV-2]]></kwd>
<kwd lng="es"><![CDATA[niños]]></kwd>
<kwd lng="es"><![CDATA[adolescentes]]></kwd>
<kwd lng="es"><![CDATA[México]]></kwd>
<kwd lng="en"><![CDATA[seroprevalence]]></kwd>
<kwd lng="en"><![CDATA[SARS-CoV-2]]></kwd>
<kwd lng="en"><![CDATA[children]]></kwd>
<kwd lng="en"><![CDATA[adolescents]]></kwd>
<kwd lng="en"><![CDATA[Mexico]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Riley]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Ainslie]]></surname>
<given-names><![CDATA[KEC]]></given-names>
</name>
<name>
<surname><![CDATA[Eales]]></surname>
<given-names><![CDATA[O]]></given-names>
</name>
<name>
<surname><![CDATA[Walters]]></surname>
<given-names><![CDATA[CE]]></given-names>
</name>
<name>
<surname><![CDATA[Wang]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Atchison]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Resurgence of SARS-CoV-2: Detection by community viral surveillance]]></article-title>
<source><![CDATA[Science]]></source>
<year>2021</year>
<volume>372</volume>
<numero>6545</numero>
<issue>6545</issue>
<page-range>990-5</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Irfan]]></surname>
<given-names><![CDATA[O]]></given-names>
</name>
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Tang]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<name>
<surname><![CDATA[Wang]]></surname>
<given-names><![CDATA[Z]]></given-names>
</name>
<name>
<surname><![CDATA[Bhutta]]></surname>
<given-names><![CDATA[ZA]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Risk of infection and transmission of SARS-CoV-2 among children and adolescents in households, communities and educational settings: A systematic review and meta-analysis]]></article-title>
<source><![CDATA[J Glob Health]]></source>
<year>2021</year>
<volume>11</volume>
<numero>05013</numero>
<issue>05013</issue>
</nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Davies]]></surname>
<given-names><![CDATA[NG]]></given-names>
</name>
<name>
<surname><![CDATA[Klepac]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
<name>
<surname><![CDATA[Liu]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Prem]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<name>
<surname><![CDATA[Jit]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Eggo]]></surname>
<given-names><![CDATA[RM]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Age-dependent effects in the transmission and control of COVID-19 epidemics]]></article-title>
<source><![CDATA[MedRxiv]]></source>
<year>2020</year>
</nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Romero-Martínez]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Barrientos-Gutiérrez]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
<name>
<surname><![CDATA[Cuevas-Nasu]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
<name>
<surname><![CDATA[Bautista-Arredondo]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Colchero]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Gaona-Pineda]]></surname>
<given-names><![CDATA[EB]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Metodología de la Encuesta Nacional de Salud y Nutrición 2020 sobre Covid-19]]></article-title>
<source><![CDATA[Salud Publica Mex]]></source>
<year>2021</year>
<volume>63</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>444-51</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rogan]]></surname>
<given-names><![CDATA[WJ]]></given-names>
</name>
<name>
<surname><![CDATA[Gladen]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Estimating prevalence from the results of a screening test]]></article-title>
<source><![CDATA[Am J Epidemiol]]></source>
<year>1978</year>
<volume>107</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>71-6</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Viner]]></surname>
<given-names><![CDATA[RM]]></given-names>
</name>
<name>
<surname><![CDATA[Mytton]]></surname>
<given-names><![CDATA[OT]]></given-names>
</name>
<name>
<surname><![CDATA[Bonell]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<name>
<surname><![CDATA[Melendez-Torres]]></surname>
<given-names><![CDATA[GJ]]></given-names>
</name>
<name>
<surname><![CDATA[Ward]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Hudson]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Susceptibility to SARS-CoV-2 infection among children and adolescents compared with adults: a systematic review and meta-analysis]]></article-title>
<source><![CDATA[JAMA Pediatr]]></source>
<year>2021</year>
<volume>175</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>143-56</page-range></nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Pollán]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Pérez-Gómez]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
<name>
<surname><![CDATA[Pastor-Barriuso]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<name>
<surname><![CDATA[Oteo]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Hernán]]></surname>
<given-names><![CDATA[MA]]></given-names>
</name>
<name>
<surname><![CDATA[Pérez-Olmeda]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Prevalence of SARS-CoV-2 in Spain (ENE-COVID): a nationwide, population-based seroepidemiological study]]></article-title>
<source><![CDATA[Lancet]]></source>
<year>2020</year>
<volume>396</volume>
<numero>10250</numero>
<issue>10250</issue>
<page-range>535-44</page-range></nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Miller]]></surname>
<given-names><![CDATA[JC]]></given-names>
</name>
<name>
<surname><![CDATA[Danon]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
<name>
<surname><![CDATA[O&#8217;Hagan]]></surname>
<given-names><![CDATA[JJ]]></given-names>
</name>
<name>
<surname><![CDATA[Goldstein]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<name>
<surname><![CDATA[Lajous]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Lipsitch]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Student behavior during a school closure caused by pandemic influenza A/H1N1]]></article-title>
<source><![CDATA[PLoS ONE]]></source>
<year>2010</year>
<volume>5</volume>
<numero>5</numero>
<issue>5</issue>
</nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Stern]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Lajous]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[De la Rosa]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
<name>
<surname><![CDATA[Goldstein]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[On the increasing incidence of SARS-CoV- 2 in older adolescents and younger adults during the epidemic in Mexico]]></article-title>
<source><![CDATA[Salud Publica Mex]]></source>
<year>2021</year>
<volume>63</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>422-8</page-range></nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Weisberg]]></surname>
<given-names><![CDATA[SP]]></given-names>
</name>
<name>
<surname><![CDATA[Connors]]></surname>
<given-names><![CDATA[TJ]]></given-names>
</name>
<name>
<surname><![CDATA[Zhu]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Baldwin]]></surname>
<given-names><![CDATA[MR]]></given-names>
</name>
<name>
<surname><![CDATA[Lin]]></surname>
<given-names><![CDATA[W-H]]></given-names>
</name>
<name>
<surname><![CDATA[Wontakal]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Distinct antibody responses to SARS-CoV-2 in children and adults across the COVID-19 clinical spectrum]]></article-title>
<source><![CDATA[Nat Immunol]]></source>
<year>2020</year>
<volume>22</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>25-31</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lessler]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Grabowski]]></surname>
<given-names><![CDATA[MK]]></given-names>
</name>
<name>
<surname><![CDATA[Grantz]]></surname>
<given-names><![CDATA[KH]]></given-names>
</name>
<name>
<surname><![CDATA[Badillo-Goicoechea]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<name>
<surname><![CDATA[Metcalf]]></surname>
<given-names><![CDATA[CJE]]></given-names>
</name>
<name>
<surname><![CDATA[Lupton-Smith]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Household COVID-19 risk and in-person schooling]]></article-title>
<source><![CDATA[Science]]></source>
<year>2021</year>
<volume>372</volume>
<numero>6546</numero>
<issue>6546</issue>
<page-range>1092-7</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="journal">
<collab>UNICEF Innocenti Research Centre</collab>
<article-title xml:lang=""><![CDATA[COVID-19: effects of school closures on foundational skills and promising practices for monitoring and mitigating learning loss]]></article-title>
<person-group person-group-type="author">
<name>
<surname><![CDATA[Alban-Conto]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<name>
<surname><![CDATA[Akseer]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Dreesen]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
<name>
<surname><![CDATA[Kamei]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Mizunoya]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
</person-group>
<source><![CDATA[Innocenti Working Papers]]></source>
<year>2021</year>
<volume>30</volume>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
