As more time has passed in the pandemic, more variants of concern have emerged.
And as they evolve and become more transmissible, many people are wondering whether we're likely to get a variant that can elude testing.
Some doctors have warned people against relying on a negative RAT result to show they do not have COVID-19. While the makers of RATs have hit back, blaming a lack of education about how and when to use the tests.
Alongside vaccination and boosters, education and access to COVID-19 testing will be what set Australia apart in the race to end the pandemic.
But what will that look like in the months or years to come?
What's the standard for sufficient COVID-19 testing?
In May 2020, the World Health Organization (WHO) advised governments that before they relaxed restrictions or reopened borders, they should have a positive test rate of 5 per cent or lower for at least 14 days.
WHO Health Emergencies Programme executive director Mike Ryan said: "You know you're missing a lot of cases if 80 or 90 per cent of the people you test are positive."
There are two ways to lower a test positivity rate:
- Decrease the number of positive tests
- Increase the total number of tests
How do Australia's testing rates compare to the rest of the world?
During the first two years of the pandemic, Australia's elimination strategy was one of the most effective in the world.
But this year, the situation has shifted.
While Australia has reported 9,225,519 cases since early 2020, 96 per cent have been from this year, leading to Australia's global ranking of cases, hospitalisations and deaths being among the world's highest.
A chart from Our World in Data shows the number of daily tests per 1,000 people has noticeably dropped.
So how do we measure up with the rest of the world?
From March 2020 to June 2022, 2.6 tests per thousand were performed in Australia, according to Our World in Data.
PCRs and RATs 'cannot be compared', we need to 'understand their roles' better
In an effort to crack down on current and emerging variants of concern, the Therapeutic Goods Administration (TGA) is conducting an ongoing review to determine how effective RATs are at detecting variants.
The TGA confirmed that four tests were removed, but this was not due to inaccuracy in detecting Omicron variants.
Three tests were removed by the supplier for business reasons, while one was cancelled by the administration for failing to provide sufficient data.
"Although RATs are not as sensitive as polymerase chain reaction (PCR) tests it is faster to perform these tests and receive a result," the TGA said.
But clinical biochemist and CEO of Pathology Technology Australia Dean Whiting said comparing the two tests was unhelpful.
"You can't compare one to the other. They're doing completely different things," he said.
Mr Whiting said it was important to remember that COVID-19 was not the only respiratory virus we were facing. It's one of many.
"We've got influenza A and B and respiratory syncytial virus to name a few," he said.
"A single PCR test can detect all of the commonly circulating respiratory viruses.
"There are roles for RATs in Australia and there are roles for PCR tests in Australia.
"We need to better understand what these roles are, which begins with better education and access."
Who is to blame for false RAT negatives — manufacturers or the people using them?
Infectious diseases physician and clinical microbiologist at the University of Queensland Paul Griffin said the TGA's review was essential in "highlighting the limitations of RATs".
"The worst thing that can happen is people believe a false negative from a RAT and go about their day whilst infectious," Dr Griffin said.
Dr Griffin isn’t the only doctor to warn people against relying on a negative RAT result.
Meanwhile, the makers of RATs have hit back, blaming false negatives on a lack of education about how and when to use the tests.
Pathology Technology Australia has defended the performance of RATs against new variants of Omicron, accusing critics of "fearmongering".
"I think a lot of the false negative results are due to incorrectly collecting the sample," Mr Whiting said.
"There is an education gap in Australia that was never filled after RATs became available.
"I've seen a lot of people just wave the swab around the inside of their nostril.
"This is not the way the manufacturer intended for you to use the test.
"If your eyes aren't watering or you're not resisting the urge to sneeze, then you're not [taking] the sample correctly."
Mr Whiting said if your RAT result was negative for COVID, then you very well might be negative for COVID.
But another possibility? You might have one of the many viruses that are circulating.
"It's worthwhile knowing which one you've got," he said.
We're likely to get a variant that's 'harder to detect with existing tests'
Three new sub-variants of Omicron – BA.2.12.1, BA.4 and BA.5 – have been detected in Australia.
The University of South Australia's Adrian Esterman said BA.4 and BA.5 were more infectious than previous COVID subvariants and were "better able to evade immunity from vaccines and previous infections".
Dr Griffin said at some point in time, we would likely get a variant that was much harder to detect with existing tests.
So where does that leave things with our current testing landscape?
Because of Australia's diverse population and geographical spread, Mr Whiting believes RATs are going to remain highly useful, especially in rural and remote areas.
"What manufacturers are doing now is developing and optimising RATs," he said.
"We're continuing to change our view on how testing should be done and the way technology should be deployed in Australia."
Mr Whiting said the future would involve greater access to potentially life-saving tests which could be carried out either by the individual or by a doctor or pharmacist, "wherever they are in Australia".
"This will help us more efficiently and effectively identify disease and illness in the population," he said.
"With the right education and awareness, RATs and PCR tests will drive better healthcare outcomes in Australia."
Is there any new technology on the horizon?
For the first time, health authorities in the United States have given the green light to a COVID-19 breathalyser, a device that is promised to deliver results in less than three minutes.
Some experts hope it will be the first of many new tools to diagnose and, therefore, improve the way we live with the virus.
There's even hope breath testing could eventually be used to detect and monitor other conditions, such as cancer.
Perena Gouma, a professor of materials science and engineering, was working on a breath test to detect the flu when COVID-19 began.
"We have developed a portable and handheld device that may provide early and rapid detection of the disease in 15 seconds, while requiring a 10-second exhale into a mouthpiece," Professor Gouma told ABC News.
But her efforts to obtain emergency use authorisation from the US Food and Drug Administration have so far been unsuccessful.
Professor Gouma said the reality was there was almost no federal funding for breath-based diagnostics.
She also said no private investors would risk funding such technology without the certainty of obtaining regulatory approval.
"If investing in training COVID sniffer dogs is an acceptable practice, what should prevent the use of breathalyser devices to detect this and other infectious diseases?" she said.
Professor Gouma is hopeful that by getting clinicians more involved with the development of breath-based diagnostics, their confidence in this type of testing will grow.
Australia still 'conservative' and 'miles behind' in testing technology
Maureen Miller, an epidemiologist at Columbia University's Mailman School of Public Health said we were "vastly under-counting what is going on in this country".
Dr Miller acknowledges COVID-19 testing technology has come a long way since the start of the pandemic.
However, she and other experts fear a reliance on at-home testing has made it difficult for authorities to track case numbers.
"Several recent studies have shown that of people who test at home, [only] between 7 and 10 per cent report their results. Perversely, positive people tend not to report their result," she said.
Mr Whiting said even PCR testing was "highly under-utilised" in Australia, and the country was "miles behind" when it came to the latest innovations in healthcare technology.
"Australia was the last country in the Asia-Pacific region to adopt the technology for identifying cancer cells in the bloodstream," he said.
"This technology has been around for years, yet we were the last in the Asia-Pacific to adopt it."
"We're still highly conservative and a long way behind many economies in the adoption of rapid-testing technology."
Mr Whiting said in order for Australia to be more efficient and provide better outcomes for people with illnesses, "we must adopt the broader funding of these kinds of technologies".
