• UK Government commissioned study working toward setting antibody level thresholds to determine protection levels
  • Building case for antibody testing to support vaccine and workplace COVID-19 strategies
  • AbC-19TM Semi-Q Rapid Test (Semi-quantitative anti-spike antibody test) results correlate with ONS findings

York, U.K. 2 March 2022: Abingdon Health plc (AIM: ABDX), a leading international developer and manufacturer of high quality and effective rapid tests, notes the publication of data1 by the Office for National Statistics (ONS) in making significant steps forward in stratifying antibody thresholds for a better understanding of protection against SARS-CoV-2 (COVID-19) infection, supporting the case for mass antibody testing to guide vaccine booster programmes and workplace COVID-19 policies.

The ‘Coronavirus (COVID-19) Infection Survey, antibody and vaccination data’ recently published an antibody threshold associated with a 67% lower risk of getting a new COVID-19 infection. This threshold was based on a study completed by The University of Oxford, The University of Manchester, UK Health Security Agency and Wellcome Trust, commissioned by the Department for Health and Social Care (DHSC) 2.

The study, which focused on the detection of antibodies against the spike protein, identified a threshold of 179 ng/ml which corresponds to 100 BAU/ml using the World Health Organization’s (WHO) standardised units3.

The study noted that the threshold was identified as providing a 67% lower risk of getting a new COVID-19 infection with the Delta variant after two vaccinations with either Pfizer or AstraZeneca vaccines, compared with someone who was unvaccinated and had not had COVID-19 before.

This study also noted that “at least 67% protection against infection was estimated to last for 2-3 months after two ChAdOx1 (Oxford AstraZeneca) doses and 5-8 months after two BNT162b2 (Pfizer) doses in those without prior infection, and 1-2 years for those unvaccinated after natural infection”. More data is to be published in due course.

Such data supports the use of antibody testing in reducing the guesswork around how individuals are responding to both vaccination and/or infection. Each individual is different and antibody testing is an important tool in helping populations to live with COVID-19. For vaccine programmes it enables prioritisation of who and when people require their next jab can be facilitated with antibody testing. For unvaccinated but previously infected individuals it provides some assurances of seroconversion and length of protection.

Abingdon Health commercially launched a semi-quantitative IgG rapid antibody test against the spike protein; AbC-19TM Semi-Q Rapid Test (“AbC-19TM Semi-Q”). Using a scorecard, the antibody concentration can be easily determined by aligning the obtained score with a predetermined antibody concentration, allowing individuals to reliably monitor immune response and antibody waning.

Using the same WHO standard, preliminary results4 indicate that 100 BAU/ml equals a level 5 on the AbC-19TM Semi-Q Rapid Test scorecard.

Furthermore, this threshold correlates with results produced in a longitudinal antibody test user study. Data (See graph) demonstrated that the father of one household who produced a level four on the AbC-19TM Semi-Q scorecard, avoided catching COVID-19 from his son who tested positive. Whereas the mother of that household, at a level one at the time, did subsequently catch the virus and test positive for COVID-19. 


Chris Yates, Chief Executive Officer of Abingdon Health, commented: “We welcome the publication of this data in being very significant for helping people to gain insights into protection against COVID-19. We look forward to further results from this study. 

“The effects of COVID-19 continue. Accurately monitoring antibody levels is important for determining if, and when, booster vaccines are required. Our own research, as well as other published data, shows there is a significant degree of variability in antibody levels between individuals, following infection and/or vaccination.

“It is our long-held belief that antibody testing is being under used particularly as people want to know their antibody status. This desire was certainly confirmed in results from an antibody testing survey we published recently. We’re passionate about making meaningful rapid testing available to all to help empower people to make informed decisions about their health. Antibody testing is another means of empowerment.”


  1. Coronavirus (COVID-19) Infection Survey, antibody and vaccination data, UK: 9 February 2022 (https:\www.ons.gov.uk\peoplepopulationandcommunity\healthandsocialcare\conditionsanddiseases\bulletins\coronaviruscovid19infectionsurveyantibodyandvaccinationdatafortheuk\latest#analysis-using-an-alternative-antibody-threshold)
  2. Wei, J et al (2022) SARS-CoV-2 anti-spike IgG antibody responses after second dose of ChAdOx1 or BNT162b2 and correlates of protection in the UK general population (pre-print) https://doi.org/10.1101/2021.09.13.21263487
  3. WHO International Standard First WHO International Standard for anti-SARS-CoV-2 immunoglobulin (human) NIBSC code: 20/136 Instructions for use.  (https://www.nibsc.org/documents/ifu/20-136.pdf)
  4. Journal of infection 83 (2021) e18-e3


Abingdon Health plc www.abingdonhealth.com/investors/
Chris Yates, Chief Executive Officer Via Walbrook PR
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About Abingdon Health

Abingdon Health is a world leading developer and manufacturer of high-quality rapid tests across all industry sectors, including healthcare and COVID-19. Abingdon is the partner of choice for a growing global customer base and takes projects from initial concept through to routine and large-scale manufacturing and has also developed and marketed its own labelled tests.

The Company offers lateral flow product development, regulatory support, technology transfer and manufacturing services for customers looking to develop new assays or transfer existing laboratory-based assays to a lateral flow format. Abingdon Health aims to support the increase in need for rapid results across many industries and locations and produces lateral flow tests in areas such as infectious disease, clinical testing including companion diagnostics, animal health and environmental testing. Faster access to results allows for rapid decision making, targeted intervention and can support better outcomes. This ability has a significant role to play in improving life across the world. To support this aim Abingdon Health has also developed AppDx®, a customisable image capturing technology that transforms a smartphone into a self-sufficient, standalone lateral-flow reader.

Founded in 2008, Abingdon Health is headquartered in York, England.