Rapid antigen testing in Australia – current role and limits

Rapid antigen tests can deliver a COVID‑19 result in 15‑30 minutes, but they are less accurate than PCR tests and currently serve only as a complementary tool in Australia’s high‑capacity testing system [1].

The country’s testing labs have handled one of the highest per‑capita PCR volumes worldwide, allowing most diagnoses to rely on the gold‑standard method with high sensitivity and specificity, according to Professor Deborah Williamson of the Doherty Institute [1]. Nevertheless, the sheer scale of testing needed to control the pandemic has prompted health officials to explore rapid tests for specific scenarios, such as frequent screening of workers in high‑risk settings or entry checks at large venues like stadiums and restaurants [1].

Rapid antigen tests detect viral proteins and can be performed at the point of care without specialist lab equipment, which makes them attractive for mass screening where PCR turnaround times are longer [1]. However, their lower sensitivity raises concerns about false‑negative results, especially in low‑prevalence environments like Australia, where a positive result could also be a false positive due to the disease’s rarity [1]. Epidemiologists stress that any positive rapid test should be confirmed by PCR, while negative results may still miss infections, limiting the tests’ reliability as a sole diagnostic tool [1].

Internationally, the World Health Organization has distributed 120 million rapid‑diagnostic tests to low‑income nations, and wealthier countries have used them to alleviate testing backlogs, but Australia’s robust PCR capacity means it has not needed to adopt rapid tests for diagnosis at scale [1]. Experts agree that more research is required to determine whether rapid antigen testing can meaningfully augment Australia’s pandemic response without compromising accuracy [1].

The open question remains: can rapid antigen tests provide enough additional coverage to justify their deployment in a low‑prevalence, high‑PCR‑capacity setting, or will they add complexity without clear benefit?