The Adelaide Showgrounds hub, which at its peak immunised around 4000 people each day, will close at 2pm this afternoon.

The clinic first opened at the end of April 2021 when the nation’s vaccination rollout began ramping up.

The state government announced its closure two weeks ago, citing dwindling demand and staffing shortages across the health system.

Pharmacies and GPs have since been administering the majority of the state’s COVID-19 vaccinations, with people over the age of 30 now eligible to receive a fourth jab.

A pop-up COVID-19 vaccination clinic also opened in the western park lands on Wednesday.

The walk-in clinic, off Sir Donald Bradman Drive at Ellis Park/Tampawardli (Park 24), is open from 8.30am to 5pm every day and offers the Pfizer vaccine to anyone over the age of five – including the fourth dose for people aged over 30.

A new Myer Centre clinic at Rundle Mall will also reopen on Friday.

Health Minister Chris Picton said the two sites would have greater capacity combined than the Wayville vaccination hub.

Just under 94 per cent of South Australians over the age of 12 have received two doses of a COVID-19 vaccine, while 73.6 per cent of those eligible have come forward for a booster shot.

South Australia recorded two deaths and 4408 cases of COVID-19 on Wednesday, up from 3668 the day before.

There are currently 245 people with COVID in hospital, but this includes people in hospital for other reasons who incidentally have the virus.

The new Omicron BA.4 and BA.5 subvariants has prompted the rise in infections.

The two subvariants have the same severity as the previous BA.1 and BA.2 mutations of the virus but are considered more infectious and better able to evade immunity from vaccines.

Latest genome sequencing, conducted last week, shows just under 55 per cent of test samples were BA.4 and BA.5 – up from 24 per cent the week before.