COVID-19 in children: analysis of the first pandemic peak in England by Ladhani, SN, Amin-Chowdhury, Z, Davies, HG, Aiano, F, Hayden, I, Lacy, J, Sinnathamby, M, de Lusignan, S, Demirjian, A, Whittaker, H, Andrews, N, Zambon, M, Hopkins, S, Ramsay, ME