Asymptomatic immunodeficiency-associated vaccine-derived poliovirus infections in two UK children oleh Anika Singanayagam, Dimitra Klapsa, Shirelle Burton-Fanning, Julian Hand, Thomas Wilton, Laura Stephens, Ryan Mate, Benjamin Shillitoe, Cristina Celma, Mary Slatter, Terry Flood, Robin Gopal, Javier Martin, Maria Zambon