It was the information that no one in Australia, let alone Western Australia, wanted to hear: there's been a COVID leak from a quarantine hotel.

The city of Perth last night spent its first night in a five day hard lockdown, as health authorities start a mammoth contact tracing effort to track down the virus.

As lockdowns go, it's very strict: people are only allowed out for a few essential reasons, masks are mandatory, and students due back at school have been given another week off.

So on today's Coronacast, is locking down nearly 80 per cent of the state's population with only one confirmed case an overreaction?

Also on today's show:

* We run through the latest vaccine trial results of Novavax and Johnson and Johnson. What does it all mean?

* Now that all the major trial results are in, Norman has ranked them from best to least best (hey it's amazing we have five options so quickly!)