Thank you for the hint (in the reference [1], the measurement done as in [2], which states "Collected aerosols were analysed by quantitative real-time polymeras

Thank you for the hint (in the reference [1], the measurement done as in [2], which states "Collected aerosols were analysed by quantitative real-time polymerase chain reaction (qRT-PCR) and by virus titration"), although I then don't get why the paper [1] writes that the viruses are "infectious". [1] https://www.nejm.org/doi/10.1056/NEJMc2004973 https://www.nejm.org/doi/10.1056/NEJMc2004973 [2] https://www.eurosurveillance.org/content/10.2807/1560-7917.ES2013.18.38.20590 https://www.eurosurveillance.org/content/10.2807/1560-7917.E...