New Zealand is one of only 20 countries in the world to have a confirmed case of the South African variant of Covid-19. On Monday, the Australian Government suspended quarantine free travel for New Zealanders for at least 72 hours in the wake of a community case in Northland. The variant is a more highly transmissible version of the virus. Susie Ferguson speaks to University of Otago virologist Jemma Geoghegan.