Rapid urbanisation thought to be damaging adolescent health, as researchers say need for medication and diagnostic tests is urgent

Millions of teenagers in Africa are suffering from asthma with no formal diagnosis as the continent undergoes rapid urbanisation, researchers have found.

The study, published in the Lancet Child and Adolescent Health, involved 27,000 pupils from urban areas in Malawi, South Africa, Zimbabwe, Uganda, Ghana and Nigeria. It found more than 3,000 reported asthma symptoms, but only about 600 had a formal diagnosis.