Australians will soon be testing themselves for COVID-19 from the comfort of their own home.
If you've been tested for the virus in Australia, you've had the "gold standard" Polymerase Chain Reaction test administered by a health professional.
But in just over a month, you'll have a new means of getting tested. Rapid antigen tests, some producing a result within 20 minutes, have been approved for self-use here from the beginning of November.
Antigen tests are distinct from PCR tests in a number of ways - cost, accuracy, and convenience - and will most likely become a feature of everyday life.
They've been a feature of life across Europe and the US for months, used by businesses and schools to avoid damaging closures. Soon getting tested for COVID-19 in Australia will be a matter of over-the-counter pharmacy service.
Here's what it means for you.
How do they work?
Antigen tests can be done through a nasal or saliva swab, and are usually less invasive than a PCR test. Like a pregnancy test, they show you colour bands to let you know if you're positive.
On a technical level, they detect protein on the COVID-19 virus directly from the sample taken. They work differently to the PCR test, which amplifies parts of the virus' genetic code.
Are they accurate?
That depends on the make.
Some types are over 95 per cent accurate, but that varies significantly depending on what brand you use.
The less accurate they are, the more likely to throw up a false negative. Negatives are particularly problematic. A false positive is inconvenient to the user, forcing them to stay home unnecessarily. But a false negative can lead a COVID-positive user to head into the community.
But even the most effective antigen tests are not quite as accurate as a PCR test, which can detect lower levels of virus.
Antigen tests work best during high levels of transmission. Given we're about to open up, that'll be soon.
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So why use them?
Quicker, cheaper and more flexible.
Some models can produce a result in just 15 minutes. You could test yourself in the morning and, in the time it takes to get dressed and have breakfast, have a result.
That adds certainty for schools and businesses, with students and employees not needing to isolate for days as they await their results.
Antigen tests also play a key role in detecting asymptomatic cases. People without symptoms don't front testing clinics, but are more likely to take a quick test to double-check if they're worried.
They're also cheaper than the PCR tests, meaning they can be rolled out at a higher volume for the same cost.
How much will they cost?
More than 70 companies are in the process of applying for approval in Australia. Each will likely set their own price once they're given the green light.
Taking overseas as a guide, there will likely be a big price range. In the US, you can get a test for less than $7. But like anything, you get what you pay for.
Antigen tests can cost around $60 in the UK. In Singapore, they're as little as $10.
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Who's footing the bill?
For the most part, you.
PCR tests are free - they're covered by Medicare - but don't expect that to apply to rapid tests.
Andrew Barr says, apart from when they're required to enter government-run sites, Canberrans will be footing the bill themselves.
The Singaporean government has mailed test kits to every household free-of-charge, but there is no current commitment to do the same here.
But businesses say, at the volume required to properly protect their workforce and customers, funding their own tests will be financially unsustainable. They're calling for the federal government to step in.
What happens if I test positive?
We don't know yet.
There is a lack of detail about how at-home tests will fold into Australia's COVID-19 response.
It seems likely those who test positive will need to have their result confirmed by a PCR test, and the TGA says states and territories may legally require that.
The Australian-designed Ellume test is linked to a user's smartphone. In the US, a result is automatically sent to health authorities through an encrypted cloud.
Aren't we already using them?
Yes, but this is different.
Antigen tests are already used in a number of Australian settings, including aged care centres and quarantine facilities.
Commonwealth Bank and Westpac both trialed the tests in COVID-ravaged parts of Sydney last month. They said the response was overwhelmingly positive.
But only health professionals, usually a pharmacist or a nurse, are currently allowed to administer them. There are more than 30 types approved for that kind of use.
That all changes from November. Australians will be able to test themselves, meaning they will be used much more widely.