From August to October, daily numbers have dropped consistently from more than 7000 to around 2000.
On Tuesday this week, SA Health reported 2326 tests had been performed.
“Our COVID-19 testing rates have been falling in recent months,” SA Health said.
“We need all South Australians and anyone visiting SA to keep getting tested with any symptoms, no matter how mild.
“It’s quick, free and at most testing sites you don’t need a referral.”
The falling numbers reflect the limited infections in SA with only 45 cases of coronavirus reported since April and no cases involving community transmission for a number of weeks.
The call for increased testing also came as SA on Thursday extended its buffer zone with Victoria, easing COVID-19 restrictions on border communities.
The zone has increased from 40km to 70km on each side of the border, allowing more people to travel into SA or return from trips into Victoria without need to quarantine.
People travelling from states other than Victoria, who transition through Mildura, are also allowed to come into the state without being forced into isolation.
Travellers are being checked at the border to ensure they are not from Victoria or Mildura locals and must not have stopped in the regional town.
Police Commissioner Grant Stevens said the increased border zone would give regional communities the chance to once again access services in SA that they had used in the past.
“But it also means that South Australians who have ties or obligations within Victoria have the ability to go in and undertake their business,” he said.
“It was a balanced decision that provided opportunity for those people who needed it most yet still protected South Australians from the increased risk from COVID-19.”
SA is also looking at easing requirements on close border communities from weekly fortnightly tests for coronavirus but no decision has yet been made.
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