Rapid antigen tests, hailed as a game-changer in the fight against COVID-19, will be available to buy in supermarkets as soon as next week.
The Chinese-manufactured Hough Pharma nasal tests, which have a turnaround time of about 15 minutes, will be available from a selected 700 Coles stores nationally next week.
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It comes after Health Minister Greg Hunt announced the Therapeutic Good Administration (TGA) had approved the use of the home testing kits from November 1.
Offering fast results and simply administered in a non-medical setting, they offer advantages over other COVID-19 tests such as the standard polymerase chain reaction or PCR test.
Here is what you need to know.
What is a rapid antigen test?
Antigen tests are a quick and easy way to look for a specific antigen – a term for any foreign substance, such as a virus or bacteria.
Antigen tests for flu or strep throat, for example, can be done in a doctor's office without expensive equipment and give results in 10 to 15 minutes.
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How do they work?
Think of it like an at-home pregnancy test.
In a coronavirus antigen test, you put a bodily sample such as a throat swab onto a specially treated strip, which then uses a colour or marker to say whether the novel coronavirus is present.
The antigen test works by looking for a unique part of the novel coronavirus, such as a specific protein on one of its namesake "corona" spikes.
If that specific protein is present in detectable quantities, then the test returns a positive result.
How to purchase a rapid antigen test?
Rapid antigen tests will be available from supermarkets around the country, with 700 Coles outlets stocking the kits as early as next week.
A spokesperson for Woolworths said they were also looking to roll out rapid testing kits, first starting with states like New South Wales and Victoria, that are currently managing outbreaks.
How much is a rapid antigen test
It's believed kits will be available in packs of two or five in store and online.
Estimates have the price of the kits pegged at between $10 to $30.
Where can they be done?
Rapid-antigen tests are already being used in a number of settings across Australia, such as aged care homes and some quarantine facilities and workplaces.
The TGA has approved 33 rapid tests for use under supervision.
The kits available from next week are the first of eight rapid antigen tests approved for at-home use.
In a statement, the TGA said any rapid antigen tests approved for at-home use would come with simple-to-use instructions, fact sheets and a supporting phone helpline or explainer video.
Benefits of rapid antigen testing versus PCR
The TGA says rapid antigen tests can detect the virus in the acute phase of infection – especially in the week before symptoms are apparent, and the first week of symptoms being apparent.
And unlike results from PCR testing that take hours or days, rapid antigen tests can return them in 30 minutes or less.
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How accurate are rapid antigen tests?
Advisor to the World Health Organisation (WHO) and Professor of Epidemiology at University of NSW, Professor Mary Louise McLaws said some tests are "close to 100 per cent" accurate.
"They're relatively cheap and they do have very good accuracy, particularly when you use them a couple of times in a row," she said.
They are most accurate in settings with a high transmission rate of coronavirus.
"In the wider Australian community settings where there are low rates of COVID-19, the tests are less accurate as there is a higher risk of both false positive and false negative results," the TGA said.
The current TGA advice is a PCR test must be carried out to confirm rapid antigen test results.
"While a goal of no or very low community transmission is being pursued, conducting confirmatory testing by PCR is very important if someone gets a positive test from a rapid antigen test," the TGA says.
"It is not acceptable to just repeat the rapid antigen test in the hope of the second test being negative.
"Any positive result needs follow up with a PCR test."
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What is the overseas experience like?
In the UK, rapid antigen tests have been used widely to complement PCR testing during the pandemic.
The tests have been offered free to millions of people in England, for use at home or at test centres, workplaces and schools.
They are widely used for school students in Britain who are close COVID-19 contacts.
They have proven a safe and accurate alternative to home isolation and enable children to remain in class.
Some countries also accept a negative rapid antigen test result from UK travellers as a condition of entry.
The Singapore government has also distributed millions of free kits to its citizens.
