Monash Health has been part of an exciting pilot study led by The Doherty Institute to evaluate the performance and feasibility of rapid COVID-19 tests, with the pilot results published this week in The Lancet Regional Health – Western Pacific.
Rapid antigen tests are quicker and more portable than the standard PCR (polymerase chain reaction) tests currently being used to test for COVID-19. Antigen tests detect the SARS-CoV-2 viral protein directly from clinical samples, whereas the ‘gold standard’ PCR tests detect amplified viral RNA (ribonucleic acid), making PCR tests significantly more sensitive.
Antigen tests provide a rapid result and are easily accessible and relatively low cost, which is why they have been promoted as a means of increasing population-level surveillance testing and enabling testing at or near the point-of-care.
The study conducted by Melbourne researchers, including Monash Health’s Associate Professor Maryza Graham, recruited participants presenting for COVID-19 testing at three Melbourne metropolitan hospitals – Monash Health, The Royal Melbourne Hospital and Austin Health – during a period of low COVID-19 prevalence, between 28 September 2020 to 14 November 2020.
Associate Professor Maryza Graham, who co-authored the study, says the antigen testing could contribute to Australia’s ‘COVID Normal’ future.
“While PCR tests remain the ‘gold standard’ for COVID-19 testing, some novel tests may play an important role in the overall public health strategy given they are rapid and have the potential to be performed near the point of care. Innovative testing may contribute to enhance COVID-19 surveillance that is the cornerstone of sustaining a ‘COVID Normal’.”
The test, also known as the Abbott PanBioTM COVID-19 antigen point-of-care test, was performed alongside the gold standard PCR test. The Abbott PanBioTM COVID-19 antigen test’s specificity was 99.96%, whereas sensitivity amongst participants with PCR-confirmed infection was dependent upon the duration of symptoms reported.
The antigen tests performed best in the first few days after symptom onset, which was consistent with the test’s intended use. The study found many challenges around implementing these tests, ranging from how to conduct the tests in a safe environment to choosing the population to test (symptomatic or asymptomatic) considering the occurrence of false-positive and false-negative results.
Given the high specificity, in low-prevalence settings antigen-based tests may be most useful in rapidly triaging public health and hospital resources while expediting confirmatory PCR testing. But considering the limitations in test sensitivity and the potential for rapid transmission in susceptible populations, particularly in hospital settings, careful consideration is required for implementation of antigen testing in a low prevalence setting.
With the support of Dr Alastair Meyer, Dr Nathan Bushby and the dynamic teams from Casey Emergency Department, plus Kirsten Holden and the Clayton and Casey Screening clinic staff, hundreds of rapid tests have been performed to assess test performance and feasibility in real-life scenarios.
Antigen tests such as this one are being considered at a state and federal level. Using the findings from this study and others similar, a framework has been developed that will assist with the planning around how antigen testing can be scaled-up and used throughout Australia.