South Australia registered two new locally acquired Covid-19 cases on Thursday.
Prime Minister Steven Marshall confirmed the new infections, with the South Australian cluster rising to 14 cases.
He said the new cases, which were a brother and a sister, both in their 20s, were both at Tenafeate Creek Winery at the same time as a previously registered case.
It comes after six new cases were linked to two “super-spreading” events on Wednesday – five in connection with the winery on Sunday afternoon from 1.45pm to 4.30pm and a further case from The Greek on Halifax restaurant on Saturday night.
Sir. Marshall said that “no doubt” locking would have a strong impact on the economy, individuals and businesses.
But he said the authorities wanted to move as quickly as possible to restrict movement and chase all cases in the community.
Premier said it was “too early” to say whether the seven-day shutdown should be extended.
“We have not seen an explosion (of cases) … but we will probably see further cases,” Mr Marshall warned.
“I am very grateful that we moved to a lockdown. If we waited another 12-24 hours, we would be in a completely different situation.
“I am unusually hopeful that we have been able to stop the spread of this disease, and hopefully within the seven days we can stop that death in its tracks.”
Public Health Director Nicola Spurrier said the parents of the positive siblings also attended Tenafeate Creek Winery, but have so far returned a negative result.
She said not all cases from this place were related to each other, nor were they there for the same gathering, but they had all eaten indoors.
There are now 71 exposure sites listed on the SA Health website, and Professor Spurrier said she hoped South Australians continued to check it for updates.
There are currently about 4,000 people in quarantine with 13,610 people who have been to one of the mentioned exposure sites.
Professor Spurrier said she was “very concerned” about the Greek on the Halifax and Tenafeate Creek winery sites because of the test numbers.
So far, 53 of the 91 people who attended the Adelaide CBD restaurant have been tested, while only 34 of the 125 customers from the winery have been plastered.
Professor Spurrier said that anyone who attended one of these venues would be placed in hotel quarantine to complete their isolation for two weeks because they had a “slightly higher risk of getting Covid than some of our international travelers at the moment” .
A minor change to the directions was also made so that a single person over the age of 16 who lives alone or who does not live with their spouse can visit a friend or partner if no one else is home.
It is also allowed if the single person is a single parent and the only other people present in their home at the time of the visit are their children.
Under management, those who want to visit their partners are only allowed to do so if they were in a relationship before the lockdown.
Police Commissioner Grant Stevens said there was a possibility that the shutdown would be extended and understood what impact that could have on people in relationships as well as people living alone.
He said the changes gave these people an opportunity not to be separated or alone.
“We’re obviously trying to limit the number of people who could potentially be exposed to other households,” Stevens said.
“This is not free for everyone to visit friends.
“This is very limited to ensure that we enable people to maintain their general well-being and mental health.”