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Heterogeneidades de transmisión, cinética y capacidad de control del SARS-CoV-2
Kaiyuan Sun1, Wei Wang2, Lidong Gao3
1Division of International Epidemiology and Population Studies, Fogarty International Center, National Institutes of Health, Bethesda, MD, USA. kaiyuan.sun@nih.gov yhj@fudan.edu.cn.
Science (New York, N.Y.)
|November 25, 2020
Resumen
El ochenta por ciento de las infecciones por coronavirus 2 del síndrome respiratorio agudo severo (SARS-CoV-2) se originaron en solo el 15% de los casos, lo que pone de relieve una heterogeneidad significativa de transmisión. El control efectivo requiere estrategias integradas que incluyan aislamiento, cuarentena y medidas de salud pública más amplias.
Área de la Ciencia:
- Epidemiología
- Dinámica de las enfermedades infecciosas
- Salud pública
Sus antecedentes:
- La comprensión de las heterogeneidades de transmisión es crucial para el manejo de las enfermedades infecciosas.
- Los factores demográficos, de comportamiento y de intervención influyen significativamente en la propagación de la enfermedad.
- Los patrones de transmisión del síndrome respiratorio agudo severo coronavirus 2 (SARS-CoV-2) requieren una investigación detallada.
Objetivo del estudio:
- Para cuantificar las heterogeneidades de transmisión en el SARS-CoV-2.
- Para identificar los factores clave de la transmisión del SARS-CoV-2.
- Informar estrategias de control efectivas para el SARS-CoV-2.
Principales métodos:
- Análisis de datos de pacientes y contactos de Hunan, China.
- Modelado estadístico para evaluar los factores de riesgo de transmisión.
- Reconstrucción del perfil de infecciosidad del SARS-CoV-2.
Principales resultados:
- Se observó una heterogeneidad sustancial de transmisión: el 80% de las infecciones secundarias del 15% de los casos primarios.
- El riesgo de transmisión se correlacionó positivamente con la duración de la exposición y la proximidad social.
- Los cierres aumentaron la transmisión doméstica; el aislamiento / cuarentena redujeron los riesgos generales de contacto.
- El pico de infectividad se produjo justo antes de la aparición de los síntomas.
Conclusiones:
- La transmisión del SARS-CoV-2 es muy heterogénea.
- Los factores demográficos, clínicos y de comportamiento modulan el riesgo de transmisión.
- Las medidas de control integradas (aislamiento de casos, cuarentena de contacto, intervenciones en la población) son esenciales para controlar el SARS-CoV-2 debido a su cinética de transmisión.
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