On Start the Week Andrew Marr explores killer diseases and the health of the world. Kathryn Lougheed focuses on one of the smartest killers humanity has ever faced - TB. It's been around since the start of civilisation and has learnt how to adapt to different environments, so today more than one million people still die of the disease every year. As with many diseases it's the poor who are most at risk. But Sir Michael Marmot explains how it's not just those at the bottom who are adversely affected, as health and life expectancy are directly related to where you are on the socio-economic ladder. The psychiatrist Lynne Jones also explores how far mental well-being is connected to human rights and the social and political worlds in which we live. She trained in one of Britain's last asylums and has travelled the world treating traumatised soldiers and civilians. Professor John Powell is interested in how far the digital world can help improve health and access to health care - from interventions for heart attacks to the treatment of depression. There are more than two hundred thousand health apps on the internet, but just how effective are they?

Producer: Katy Hickman.