RESUMEN
SARS-CoV-2 emerged in late 2019 and caused a pandemic, whereas the closely related SARS-CoV was contained rapidly in 2003. Here, an experimental set-up is used to study transmission of SARS-CoV and SARS-CoV-2 through the air between ferrets over more than a meter distance. Both viruses cause a robust productive respiratory tract infection resulting in transmission of SARS-CoV-2 to two of four indirect recipient ferrets and SARS-CoV to all four. A control pandemic A/H1N1 influenza virus also transmits efficiently. Serological assays confirm all virus transmission events. Although the experiments do not discriminate between transmission via small aerosols, large droplets and fomites, these results demonstrate that SARS-CoV and SARS-CoV-2 can remain infectious while traveling through the air. Efficient virus transmission between ferrets is in agreement with frequent SARS-CoV-2 outbreaks in mink farms. Although the evidence for virus transmission via the air between humans under natural conditions is absent or weak for SARS-CoV and SARS-CoV-2, ferrets may represent a sensitive model to study interventions aimed at preventing virus transmission.
Asunto(s)
Microbiología del Aire , COVID-19/transmisión , Hurones/virología , SARS-CoV-2 , Síndrome Respiratorio Agudo Grave/transmisión , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Aerosoles , Sustitución de Aminoácidos , Pelaje de Animal/virología , Animales , COVID-19/virología , Modelos Animales de Enfermedad , Femenino , Fómites/virología , Subtipo H1N1 del Virus de la Influenza A , Modelos Biológicos , Infecciones por Orthomyxoviridae/transmisión , Polimorfismo de Nucleótido Simple , SARS-CoV-2/genética , Síndrome Respiratorio Agudo Grave/virología , Factores de Tiempo , Carga Viral , Zoonosis Virales/transmisión , Zoonosis Virales/virología , Esparcimiento de VirusRESUMEN
SARS-CoV-2, a coronavirus that emerged in late 2019, has spread rapidly worldwide, and information about the modes of transmission of SARS-CoV-2 among humans is critical to apply appropriate infection control measures and to slow its spread. Here we show that SARS-CoV-2 is transmitted efficiently via direct contact and via the air (via respiratory droplets and/or aerosols) between ferrets, 1 to 3 days and 3 to 7 days after exposure respectively. The pattern of virus shedding in the direct contact and indirect recipient ferrets is similar to that of the inoculated ferrets and infectious virus is isolated from all positive animals, showing that ferrets are productively infected via either route. This study provides experimental evidence of robust transmission of SARS-CoV-2 via the air, supporting the implementation of community-level social distancing measures currently applied in many countries in the world and informing decisions on infection control measures in healthcare settings.