Free rapid antigen tests makes economic sense for governments

Authors: Professor Jonathan Karnon,¹ Professor Billie Bonevski,¹ and Associate Professor Hossein Afzali¹

1. Flinders University

The full article published in The Conversation can be found HERE.

Published in the Conversation, an economic analysis of a policy of free government-funded rapid antigen tests for all Australians concluded that even minor reductions in COVID transmission rates due to increased early testing would justify the costs of a policy to fund free rapid antigen tests.
Testing interrupts the spread of COVID by allowing countries to rapidly identify new cases, isolate affected people and their close contacts, and thereby slow further transmission of the disease. The emergence of the highly transmissible Omicron variant, coinciding with a relaxation of public health restrictions and the social festive season, led to a surge in COVID cases in Australia, swamping the PCR testing system Australia relied on to confirm COVID cases. Governments then pivoted towards using rapid antigen tests to confirm positive cases, which can give results in 15 minutes, although they’re not as accurate as PCR tests.

Professor Jonathan Karnon, Professor Billie Bonevski and Associate Professor Hossein Afzali from Flinders University developed a “decision tree” model which represents the testing pathways for a hypothetical group of 10,000 people who are concerned that they may have COVID, but they do not have COVID-like symptoms. They used this model to estimate the number of COVID-positive people isolating before developing symptoms noting that it is key people isolate as early as possible, to reduce the risk of spread to others. In the absence of empirical estimates of how people would test for COVID with and without government-funded RATs, a range of scenario analyses were undertaken.

In one scenario, it was assumed 10% of a cohort of 10,000 concerned people have COVID and that 2,000 of the 10,000 would buy rapid antigen tests if not government funded. Providing free rapid antigen tests for 10,000 people would cost the government $100,000 but there would be cost savings due to reduced use of PCR testing. The net cost effect was estimated to be additional costs to the government of around $52,000, for which 464 people with COVID would isolate early. COVID positive people who don’t know they’re positive and do not isolate early will spread it to others, leading to more ill health and more time off work. Some will need to go to hospital, be in intensive care, and be put on a ventilator. And some will die. A proportion of those who do recover from the initial phase of the infection will have lingering symptoms from the virus, known as “long COVID”. All of these outcomes impose costs to people, the health system and the economy. The avoidance of ill health and associated impacts on individuals and the economy from 464 people with COVID isolating early were suggested to represent good value for the extra $52,000 that the government would spend on tests.

Constraining the spread of COVID is important for many reasons, including avoiding short- and long-term health effects and reducing the burden on the health system and the economy. Easy and equitable access to testing is a cornerstone of the public health response to COVID. The authors suggest it also makes economic sense.

Since publishing the Conversation article, the authors have undertaken a survey of the Australian population’s stated intentions with respect to COVID testing with and without government-funded RATs. They are currently updating the original modelling to reflect these data, as well as expanding the modelling to estimate effects on COVID cases, healthcare costs and quality adjusted life years (QALYs).