LONDON—Scientists in London have found that a significant proportion of mobile phones in Britain are contaminated with faecal bacteria. This news was announced on Global Handwashing Day 2011 by Dr Val Curtis, Director of the Hygiene Centre at the London School of Hygiene & Tropical Medicine. She talks to Peter Goodwin about the significance of the finding they’ve made — jointly with Queen Mary College — and the importance of washing hands with soap and water after going to the lavatory.