Formby's health was further damaged in the influenza pandemic of 1918, during which he contracted the disease while appearing at the Manchester Hippodrome and was unable to work for a month. He was taken ill during the runs of pantomimes in both 1918 and 1919, was forced to rest for three months in 1919, and collapsed on stage during a performance in Newcastle upon Tyne in the 1920–21 pantomime season. Formby was advised by doctors to emigrate to South Africa for the benefit of his health, but he preferred to stay in Britain, with his wife and children, and continued to work. During his performances his wife would wait in the wings with ice for him to suck to stop internal bleeding, and an oxygen tent was present in the stage wings ready for emergencies.