Characterising viable virus from air exhaled by H1N1 influenza-infected ferrets reveals the importance of haemagglutinin stability for airborne infectivity. oleh Anika Singanayagam, Jie Zhou, Ruth A Elderfield, Rebecca Frise, Jonathan Ashcroft, Monica Galiano, Shahjahan Miah, Laura Nicolaou, Wendy S Barclay