Sydney enters ‘scariest’ phase of pandemic as delta variant spreads, leader says

“That makes this variant extremely dangerous because of the way cases can grow exponentially,” said Michael Plank, a data modeling expert at the University of Canterbury in New Zealand. “After just three chains of transmission, there would be eight times as many cases on average. So, where the original variant might have caused 10 cases, the delta variant could cause 80 cases in the same time, which would quickly make it impossible to control without a lockdown.”