Asthma affects more children than any other non-communicable disease - and it was a teenager who first asked her father "why can't they put my asthma medication in a spray can like hairspray?". Luckily her father ran a pharmaceutical company and got a team of scientists to work on the idea. Charlie Thiel is the one surviving member of the team. The chemist helped create a drug formulation of fine spray that reached further into the lungs than any previous treatment. Claire Bowes hears from him and his colleague Stephen Stein who has helped him document his story.

Photo: Girl using metered dose inhaler 2001 (BBC)