Australia’s drugs regulator has approved four rapid antigen Covid-19 tests for distribution throughout the country with health workers and departments among the first to use the tests than can deliver results in 15 minutes.
The Australian pathology and pharmaceutical companies approved to import and distribute the tests are required to provide the Therapeutic Goods Administration with data about the efficacy of the tests over time. Supply of the tests will be limited to accredited laboratories, medical practitioners, healthcare professionals in residential or aged care facilities, and to government health departments.
Rapid antigen tests detect the presence of viral protein from Covid-19 and may be used to diagnose the virus in a patient with symptoms. They work best in the first week of infection – after that antigens tend to drop.
While rapid antigen tests can provide a result within 15-30 minutes, they have been found to be less sensitive than the widely used polymerase chain reaction (PCR) test, which detects the viral nucleic acid and is currently the gold-standard for diagnosis. Antigen tests also differ from rapid antibody tests, with antibodies produced by the human body to eliminate the virus usually peaking two to three weeks after infection, meaning antibody tests are not usually used to diagnose a current infection. Rather, antibody tests help researchers determine how much of a population may have been exposed to a virus, and its spread.
The importation of the rapid antigen tests to Australia from four medical companies in the US and South Korea over the past few weeks is significant because it is hoped they will be useful in settings such as aged care, hospitals and food distribution where waiting up to 24 hours for the results of a PCR test can be problematic. Elective surgery patients, for example, need to be tested days before their surgery to get the results on time and need to quarantine themselves after receiving the test until their surgery to ensure they don’t catch the virus after testing. A rapid antigen test could be done right before surgery.
Life Bioscience is a biotechnology company based in Victoria that has been approved to distribute the NowCheck rapid antigen test manufactured by South Korean company BioNote Inc. The Life Bioscience director, Mark Thacker, said some of the tests had been supplied to doctors working for a major Western Australian mining company. He said the mining company eventually hoped to acquire roughly 40,000 tests per month for its workers, but a much smaller sample was being trialled to begin with.
“This test will be useful in settings where speed is paramount,” Thacker said. “If you can test someone quickly before they go on-site to their workplace, and can do that regularly, you may avoid the massive shutdowns of workplaces that we have seen in some industries.”
Prof Deborah Williamson, the deputy director of the Doherty Institute’s microbiological diagnostic unit public health laboratory, described the antigen tests as “a major development in the testing armoury available in Australia”.
However, there are caveats around their use. “They are likely to be less sensitive than a PCR test,” Williamson said, meaning they may produce false negatives.
In late August, the White House announced the US had struck a deal with US pharmaceutical company Abbott Laboratories to acquire 150m tests, deploying them to nursing homes and schools. But Williamson said it was important to monitor use of the tests in Australia and not to extrapolate data from US and other studies of the tests.
“Before the wide-scale implementation in Australia we need really good data appropriate to our context here of low prevalence, and the epidemiological context in the US is really very different,” she said.
A director of Victorian pharmaceutical company Pantonic Health, Laura Panton, said global demand for the antigen tests would increase in the coming months. Pantonic Health has secured a supply of the tests from US company Access Bio.
“First and foremost our focus is with the healthcare sector but we have also received interest from a range of industries including mining and resources and airlines,” she said.
She said while the tests were still “very new to Australia”, they wold likely be particularly valuable for screening large workforces or at major events, frequent testing in hospitals and aged care facilities, as well as helping to open up interstate and international borders safely and cost-effectively.
Meanwhile, Point of Care Diagnostics Australia’s medical business manager, Peter Merrilees, said his company had acquired about 10,000 of the tests from the US that were in the process of being shipped, and that Aboriginal Controlled Health Organisations and remote and regional communities would be logical places for the test to be trialled.