COVID antibody testing: understanding immunity

Posted: 10th June 2021

COVID-19 changed the path of humanity in 2020, but for SVI’s NRL division it meant doing a whole lot more of what they do best. 

A designated World Health Organization (WHO) Collaborating Centre, NRL is a world leader in evaluating test kits and improving the quality of laboratory testing for infectious diseases. 

“Accurate testing has been central to the fight against COVID-19,” says NRL Director, Dr Pip Hetzel. 

“The focus last year was squarely on diagnostic testing – the now-familiar nose and throat swab. But with vaccination forging ahead internationally, antibody testing of blood samples is becoming increasingly important.” 

“Investigating whether a person has developed protective antibodies – either in response to exposure to the virus or vaccination – will be key to understanding long-term immunity.” 

Exactly how long a vaccine will give the body immunity against COVID-19 is still to be established, as is their effectiveness against emerging variants of the virus. 

“Antibody testing is routinely used in public health research to measure levels of community exposure and response to infections,” Pip explains. “Point-of-care test kits are also emerging for potential use in workplaces, aiming to give quick turn-around results on a pin-prick drop of blood. However, the accuracy of many of these new tests is yet to be fully assessed.” 

This is where NRL comes in. The team’s unique expertise in quality assurance for antibody testing (also known as serology testing) is now being sought nationally and internationally. NRL is the lead agency in WHO’s worldwide assessment of new antibody test kits and has been contracted locally to provide the same services in Australia. 

The comprehensive scientific evaluation of antibody test kits requires a large number of what Pip describes as “pedigreed” serology samples: a sizeable repository of blood samples collected sequentially from individual COVID-19 patients over the course of their infection and recovery. This allows NRL to assess all test kits on the same samples, giving a comparison of performance. 

“This gives us a single source of truth to assess and compare, rigorously, each new test kit,” Pip comments. 

“WHO will use our evaluation results to determine which test kits are safe and effective for use. That makes our work really powerful and highly satisfying.” 

Learn more about NRL's work here.

*image by Fusion Medical Animation on Unsplash