RESUMEN
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.
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.
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.
Asunto(s)
COVID-19 , SARS-CoV-2 , Adolescente , Niño , Humanos , México/epidemiología , Instituciones Académicas , Estudios SeroepidemiológicosRESUMEN
BACKGROUND: An accurate estimate of the total number of cases and severity of illness of an emerging infectious disease is required both to define the burden of the epidemic and to determine the severity of disease. When a novel pathogen first appears, affected individuals with severe symptoms are more likely to be diagnosed. Accordingly, the total number of cases will be underestimated and disease severity overestimated. This problem is manifest in the current epidemic of novel influenza A/H1N1. METHODS AND RESULTS: We used a simple approach to leverage measures of incident influenza A/H1N1 among a relatively small and well observed group of US, UK, Spanish and Canadian travelers who had visited Mexico to estimate the incidence among a much larger and less well surveyed population of Mexican residents. We estimate that a minimum of 113,000 to 375,000 cases of novel influenza A/H1N1 have occurred in Mexicans during the month of April, 2009. Such an estimate serves as a lower bound because it does not account for underreporting of cases in travelers or for nonrandom mixing between Mexican residents and visitors, which together could increase the estimates by more than an order of magnitude. CONCLUSIONS: We find that the number of cases in Mexican residents may exceed the number of confirmed cases by two to three orders of magnitude. While the extent of disease spread is greater than previously appreciated, our estimate suggests that severe disease is uncommon since the total number of cases is likely to be much larger than those of confirmed cases.