Science commentator Siouxsie Wiles talks about a new study that suggests both teetotallers and those who drink too much during middle age are at increased risk of developing dementia, an Australian study finds that a multidrug-resistant superbug has become increasingly tolerant to the alcohols used in hospital hand disinfectants and she explains how spider venom may help treat a devastating form of childhood epilepsy. Associate Professor Dr Siouxsie Wiles is the head of Bioluminescent Superbugs Lab at the University of Auckland.