Friends and family are often called on to donate blood to loved ones in a medical emergency or ahead of routine surgery. But across the continent, there is a shortfall in blood needed for life saving transfusions. The World Health Organisation estimates that they are only meeting half the need. Aisha Dafalla and Kennedy Sanya are Kenya’s biggest donors. Between them they have donated more than 170 litres of blood. So, what do they think can be done to get more people involved?