Understanding the basics
An individual’s right to “know their COVID-19 antibody status”
The implications of knowing your antibody status
Immune status and opening up the economy
Simple neutralising antibody testing

Abingdon Health is assessing how COVID-19 (SARS-CoV-2) antibody testing can be used to unlock economies safely and conveniently for the public. In a series of blog posts covering travel, workplaces, and events, we will demonstrate how antibody testing will be central to this. In this blog, we look at the individual, their right to know their antibody status, and the positive impact this could have.

Understanding the basics

SARS-COV-2 virus being attached by antibodiesFollowing vaccination, the immune system makes IgG antibodies to the spike protein of the SARS-CoV-2 virus. This type of antibody includes those which neutralise the virus itself and are known as “neutralising antibodies.” When an individual is infected with SARS-CoV-2, those antibodies are produced alongside other antibody types to different parts of the virus, such as the internal ‘nucleocapsid protein’. When testing, it is important to look for the correct type of antibodies: IgG antibodies to the spike protein, including neutralising antibodies that hinder the virus’ ability to enter the cells. Tests which target antibodies to the nucleocapsid protein do not prove the body has developed the capability to defeat the infection, as Nucleocapsid proteins are responsible for viral replication with infected cells.1,2

Evidence3,4,5,6 is building regarding the importance of neutralising antibodies in indicating immunity.

As shared on the UK Government website,7 following vaccination with the COVID-19 Oxford / AstraZeneca vaccine, a neutralising antibody response was demonstrated in ≥98% of participants at 28 days after the first dose and >99% at 28 days after the second.

A recent study by the University of Birmingham8, in collaboration with Public Health England, on the Pfizer / BioNTech vaccine showed that after their second vaccine, spike-specific antibodies were detected in all participants, all of whom were over the age of 80. A further study9 looking at the effect of the Pfizer / BioNTech coronavirus vaccine found that almost all recipients generated a “robust” immune response after just one dose. The research by Sheffield and Oxford Universities looked at the immune response in 237 health workers and found that the Pfizer vaccine generated antibody and T-cell responses that would help fight off a COVID-19 infection in 99 per cent of people.

One of Abingdon’s scientific advisors, Professor Lawrence Young, Virologist and Professor of Molecular Oncology at the University of Warwick notes:

“The use of IgG -spike antibody testing offers a vital tool in the continued battle against the SARS-CoV-2 virus and its variants. In addition to the need for national and international health agencies to know the immunity status of the population as a whole, there is increasing need for an individual to know their own status either before, during or following a vaccination program. How long protective immunity lasts after vaccination is a key issue that will need to be carefully monitored”.

An individual’s right to “know their COVID-19 antibody status”

Since all vaccines are not 100% efficacious, the immune response will vary significantly between individuals. Zimmerman and Curtis10 published a comprehensive review of data on individual responses to vaccines and found that many different elements can contribute to substantial variations in immune responses. These variations depend on many factors including age, sex, the presence of comorbidities or other external and environmental factors such as pre-existing immunity, alcohol consumption, exercise, and sleep. It seems fair and reasonable to allow individuals to measure their own antibody response and to know their own status.

The implications of knowing your antibody status

woman working at home as she has no COVID-19 antibodiesKnowing your COVID-19 antibody status is likely to influence your behaviour. A couple of real-life examples are set out below:

1. Claire had the first dose of the Oxford/AstraZeneca vaccine and decided to return to work. Claire had underlying health issues, but felt she was safe after the first dose. A neutralising antibody test gave a negative result three weeks after the first dose. This made Claire reconsider her decision to return to work and wait until she was tested again after receiving the second dose.

2. Harry is in his 70s and was tested for neutralising antibodies 4 weeks after the second dose of the Oxford/AstraZeneca vaccine. The result came back as positive, and this reassured Harry that the vaccine had worked and gave him confidence to leave his home and visit friends and family.

In both situations the neutralising antibody test had a positive influence on the individual’s behaviour.

Even when restrictions lift, anxieties and risks will remain: the virus is not going to disappear over night. Therefore, appropriate risk management tools have to remain for which antibody tests need to be included.

Immune status and opening up the economy

SARS-CoV-2 neutralising antibody testing would also reduce the need for people to test themselves several times a month, allowing for a more efficient reopening of the economy. It is clear that a wide range of test types will be required, including antigen, PCR and neutralising antibody tests. But, as the proportion of the population who has developed immunity to COVID-19 either through infection or through vaccination increases, the benefits of neutralising antibody testing also increases. The number of tests required could reduce, possibly to one test per person every three months, and the results can be used across a range of areas such as travel, returning to workplaces, and going to events. This reduces the cost and burden of testing significantly.

The AbC19TM test offers a simple solution to neutralising antibody testing

The AbC19TM lateral flow neutralising antibody tests is easy to administer. It consists of a blood finger prick test and it takes only 20 minutes to provide a result. No large laboratory equipment is needed, and the result can be recorded on a smart phone app and a QR code issued if required that can be used for a time limited period (e.g. three-months) for multiple purposes.

It is simple, accurate, cost-effective, and connected. Currently the AbC19TM neutralising antibody test can be administered by a professional, for example your local pharmacist, and they can provide you with your neutralising antibody status.

Over time we anticipate these antibody tests being made available for home testing, in a similar way to antigen testing.

Watch our video to see how the antibody test approach works

In summary

There is a clear rationale for everyone to “know their status” when it comes to COVID-19 and neutralising antibody testing is shown to be a good proxy for immune status and the evidence for this continues to build.

Lateral flow tests that detect neutralising antibodies are a cost-effective, simple solution that gives individuals an answer about their immunity status which is likely to influence their behaviour. In addition, there are economic benefits from using neutralising antibody testing, alongside antigen and PCR testing, to reduce the volume of testing required and allow the testing results to be applied to a range of different applications; for example travelling, going to work and going to events.

The article above was authored by Chris Yates, CEO at Abingdon Health.

References

  1. https://pubmed.ncbi.nlm.nih.gov/32796155/
  2. https://www.nature.com/articles/s41467-020-19843-1
  3. https://www.nature.com/articles/s41591-021-01377-8
  4. https://pubmed.ncbi.nlm.nih.gov/33369366/
  5. https://www.medrxiv.org/content/10.1101/2021.05.07.21256847v1
  6. https://www.nejm.org/doi/full/10.1056/nejmc2103916
  7. https://www.gov.uk/government/publications/regulatory-approval-of-covid-19-vaccine-astrazeneca/information-for-healthcare-professionals-on-covid-19-vaccine-astrazeneca
  8. https://www.uk-cic.org/news/delaying-second-pfizer-vaccines-12-weeks-significantly-increases-antibody-responses-older
  9. https://www.sheffield.ac.uk/news/new-study-finds-strong-immune-response-following-covid-19-vaccination
  10. https://pubmed.ncbi.nlm.nih.gov/30867162