This week we’re exploring our microbial metropolis.

Smitha Mundasad heads into the lab to meet the bacteria that live on her skin – and on her family’s dirty laundry – to understand what’s there, and why. She goes antibiotic-hunting around her house to find out whether bacteria on a washing up sponge, a fluffy cushion, the bottom of a shoe – and even some of her kids’ play slime – could hold the key to helping scientists find new medicines. Next, Smitha wants to find out the answer to how often we should wash ourselves – and our clothes – for good health, but, as she finds out, this question is not as simple as it sounds. It turns out there's a big difference between cleanliness and hygiene – and the confusion between these two rather important words could be having an impact on our health…

Presenter: Dr Smitha Mundasad Producer: Gerry Holt Editor: Holly Squire