He found how important knowledge and understanding is in helping to manage the impact.
In 1950 John was hospitalised with polio, but with no apparent paralysis, and otherwise was active and fit; playing judo and getting into one of the secondary school football teams.
In 1958, after an undiagnosed illness requiring bed-rest he became seriously ill and was admitted to hospital (Sheffield Royal Infirmary) by his GP. A clot had formed in the left thigh and had become infected. Treatment involved three hourly injections of penicillin, heparin and pethidine.