Combating COVID-19 With Antibody Testing

The approach to fighting coronavirus has not differed to the fight against any other outbreak in terms of what is required to control it. The only real differentiator has been the speed at which tests have been created to identify a disease that no one was aware of before December 2019.

First, a test was needed to help those with the virus, to identify who had it. These were created extremely quickly – the issue with those is now logistical and ramping up production to meet the global demand.

Now, the testing task has moved onto creating a serological test. That’s a test which can measure the amount of antibodies or proteins present in the blood when the body is responding to a specific infection. These antibodies stay in the body long after symptoms have disappeared meaning that a serological test can detect who has previously had the virus.

This is important for a few reasons. First is tracking the disease. A recent study in the British Medical Journal, published in April, estimated that 78% of people with COVID-19 have no symptoms. That means they wouldn’t have been tested at the time and, without an antibody test, it could have gone totally unnoticed that they have had the condition.

That’s bad because antibodies could also mean immunity, so if you know someone has had the virus, they could go back to work or not self-isolate. In the UK, regulations are that if anyone in your house shows symptoms then everyone in that house must self isolate for 2 weeks. However, it’s entirely possible that one family member (say a doctor/nurse) brought the virus home asymptomatically, at which point another family member became ill. Then they would have to stay off work for 2 weeks as they waited to see if they contracted an illness they were already immune to.

Antibodies are also the key to vaccines, so the research being conducted into serological tests may also unlock the secret to protecting against the virus in future. This could then help to prevent any ‘second waves’ of infection.

Recent reports have suggested antibodies could play another role in helping critically ill patients recover from the virus. Doctors in China have found ‘tentative’ evidence that infusions of blood plasma from people who have recovered could help those still suffering. Doctors in China ‘gave antibody-rich plasma to 15 severely ill patients and recording striking improvements in many of them’ according to The Guardian. Watch this space for more on that.

I’ve spent the last 6 years working in the in vitro and molecular testing market, meaning that today I find myself speaking with companies right at the forefront of development for these tests. It’s a privilege to be in such close proximity to such ground breaking work.

Who's Involved? 

Given the importance of seralogical tests, many of the most innovative companies in diagnostics have directed their individual and collective attention into creating one that is accurate and scalable enough to represent an effective opposition to the virus.

Italy has been the hardest hit country in Europe and Saluggia-based DiaSorin were one of the first to announce their serological antibody test for SARS-CoV-2. They’re hope to have obtain CE marking and FDA Emergency Use Authorization by the end of April, which will allow for up to 170 patients to be tested per hour on DiaSorin’s LIAISON CL platform, of which there are approximately 5,000 in use worldwide.

US based Ortho Clinical Diagnostics’ Total Antibody Test has already received the FDA approval, one of the first to do so. These tests can also be run on Ortho’s flagship analysers which don’t require an external water source to run. This means that the potential is there to generate 150 results an hour in non-traditional laboratory environments.

On March 31 infectious disease specialist Chembio Diagnostics released a press release which announced a finger stick rapid Point of Care (POC) test which produces results in just 15 minutes using their MicroReader1 and MicroReader2 analysers. Becton Dickinson have announced a similar POC test that also provides rapid results.

One benefit to these types of finger stick tests is their simplicity. The lack of complexity to the tests has led the FDA to declare that they wouldn’t need to be reviewed for use, on the condition that they are clinically validated and not used as the sole method of diagnosis. That means they can be an important advisory tool for physicians.

In the UK a group of companies (Omega Diagnostics, Abingdon Health, BBI Solutions and CIGA Healthcare) announced an agreement with each other and Oxford University to pool expertise and resources in an attempt to develop and manufacture a lateral flow antibody test for COVID-19. This collaboration will expedite the process and assist the UK government in hitting its’ target of rolling out 100,000 coronavirus tests (of all kinds, not just serological) by the end of April. Recently, lateral flow experts Mologic have also joined, working with Omega to produce up to 46,000 of their ELISA tests a day.

And I’m sure that’s just the tip of the iceberg, with more announcements coming every day. Please, let me know if you’d like to share any further updates, as I’d be happy to keep adding to this article.

Lastly, it’s important to say that this isn’t just a race to make one test that everyone can use. All of the contributors have a massive part to play. As long as tests meet the threshold of accuracy, it’s a case of the more tests, the better, so epidemiologists can help to accurately create a picture of just where the virus has already been and predict what’s to come.

Get in Touch

I wish everyone reading this all the best during this strange and difficult times. If you have anything you’d like to discuss with me in relation to this article, please get in touch at ben.paice@lifesci-cm.com. 

Updates 
 

23 April 2020

A huge thankyou to Robert Walters who contacted me over LinkedIn to make me aware of Bio-Rad's new antibody test, announced on April 21 2020. It's a hugely exciting announcement, as the test is reported to offer more than 99% specifcity and 98% sensitivity.