WHO public health expert on the risk of Omicron

As more countries around the world report cases of Omicron, much remains unknown about the new Covid-19 variant. It's less than two weeks since Omicron was designated a "variant of concern" by the World Health Organisation, after it was first reported by scientists in South Africa. 38 countries have now reported cases: overnight the UK reported another 86 omicron infections, the US now has cases in 15 states and Australia has 17 cases in New South Wales and ACT. The designation prompted many countries - including New Zealand - to shut their borders to travellers arriving from a number of southern African nations. But is it too late? Top British scientist Prof Mark Woolhouse said the UK's border rules were "too late" to make a difference to the potential wave of Omicron. Lynn speaks with Dr Margaret Harris, an Australian public health physician and spokesperson for the World Health Organisation.