Abingdon Health plc noted the publication of an article illustrating the use of the AbC-19TM IgG spike antibody lateral flow device (AbC-19TM LFD) in semi-quantitative format and antibody responses against covid variants of concern. The article demonstrated that AbC-19TM is able to monitor antibody response following vaccination or natural infection. The paper shows differences in strength of antibody response with the Pfizer and AstraZeneca ("AZ") vaccines and the induced antibody responses to the original Wuhan variant, on which the vaccines are based. It also shows that these antibodies cross-react to the 'spike protein' of different variants of concern. This study was conducted using the AbC-19TM LFD and prototypes based on different covid variants. The results demonstrated a stronger antibody response in those vaccinated by Pfizer, compared to AZ, whilst noting the cohort vaccinated with AZ were older, which the authors noted may have an effect on antibody response. The authors used a semi-quantitative score card to record the strength of the test-line response on the LFD. They illustrated pictorially and in graphical format a proportional response of line intensity to the concentrations of neutralising antibodies in a serial dilution of the WHO standard 20/136 from 1000 IU/mL down to 7.8 IU/mL which covers the range that previous research has shown to be indicative of immunity.