"Standard tests are still the best way to track COVID-19"

https://www.abc.net.au/news/2020-09-26/15-minute-coronavirus-test/12705678

"The new 15-minute coronavirus test has potential, but standard tests are still the best way to track COVID-19"

"Four SARS-CoV-2 rapid antigen tests have been licensed for use in Australia in the past two months.

Unfortunately, rapid antigen tests for COVID-19 appear to be less sensitive than PCR tests, meaning they may give a negative result in someone who does actually have COVID-19. One of the recently licensed rapid antigen tests may give a false negative result in up to 18.3% of people with COVID-19 diagnosed by PCR. While a positive rapid antigen test result is more reliable, widespread use of these tests in asymptomatic people will result in some false positive results — that is, a positive test result in someone who doesn't have COVID-19.

At this stage, national COVID-19 guidelines don't include information on antigen tests. So a person with a positive antigen test would need to undergo a PCR test to be counted in Australia's official COVID-19 case numbers.

We're faced with a trade-off between the potential benefits of the rapid antigen tests — the ability to test larger numbers of people, consuming fewer laboratory resources, and quicker results — and the potential to miss a few cases because of the lower test sensitivity.
Despite the lower sensitivity, increasing testing rates might result in an overall net increase in the proportion of COVID-19 cases diagnosed, and therefore a public health benefit by preventing onward transmission from these cases.

One possible strategic use of these tests may be in screening people without symptoms to detect asymptomatic and pre-symptomatic infection that might otherwise go undetected. This could include people in workplaces where ongoing exposure to colleagues and the public is unavoidable, including sectors of the food supply chain or other essential services.

Because of the lower test sensitivity for the rapid antigen test, a PCR test remains most appropriate for people with symptoms, those at greater risk of poor outcomes from COVID-19, and people working in high-risk settings like aged care and health care.

While rapid antigen tests show promise, we'll need to evaluate their efficacy in Australia before we can determine their role in our fight against COVID-19."