SA closing border to Greater Brisbane from 4pm today

The South Australian border to Greater Brisbane will be slammed shut from 4pm (ACDT) today as Queensland's capital goes into a snap three day lockdown.

In response to the growing outbreak of COVID-19 in Brisbane, now at seven cases, South Australia has declared the city a hotspot and will impose a hard border.

Only returning SA residents, essential workers, and people relocating to the state will be permitted to cross the border and must isolate for 14 days on arrival.

People entering from Brisbane will also be required to get tested for COVID-19 on days one, five and 13 of the isolation period.

In addition, anyone who has entered SA from Greater Brisbane since 20 March must get tested and self-isolate, and only leave isolation once a negative result is received.

These people will also be banned from going to any venues with a COVID-management plan - venues with a capacity of more than 1,000 people.

"This would have been our Fringe and Festival, so thankfully that has now passed," SA chief public health officer Nicola Spurrier said.

"But there may be some other events that have been planned in our state over the coming days and, again, that list will be put up on our website."

This weekend's AFL match between Adelaide and the Gold Coast has also been put into jeopardy as players are not considered to be 'essential workers' and will not be allowed into SA.

NSW Health has also updated those in Byron Bay about the evolving COVID-19 situation in the region.

More testing clinics with increased hours will be established across Northern NSW today after one of the COVID-19 positive people from Brisbane visited the region over the weekend.

Health authorities in both SA and NSW have encouraged anyone with even the mildest symptoms to get tested and self-isolate until a negative result is received.

Updated at 1.59pm AEDT on 29 March 2021.