Dr Pearline Teo,
Clinical & Scientific Consultant for Laboratory Diagnostics,
Siemens Healthineers Asia Pacific
Mr Kon Gryllakis
Siemens Healthineers, Asia Pacific
The COVID-19 vaccines today were developed in a very short time; while past vaccine development timelines were 10 years, COVID-19 vaccines were developed in just one year. This meant that there is a lack of longer-term data on vaccine efficacy, and in minority populations (eg, the young or elderly).
Studies have shown that even with the same vaccine, individuals produced very different levels of antibodies. These levels also tended to drop over time. This throws up a host of questions: What is the threshold in antibody levels before an individual is conferred immunity? How long does the immunity last?
Serological assays can help to provide an indicative answer to these questions. Dr Teo suggested that serology tests can be conducted at various points at the vaccination journey to measure antibody levels: about 3-4 weeks after each dose to measure initial response; and 3, 6 ,9 months after vaccination and annually after to assess persistence of immunity. This would inform requirements for future vaccinations.
Siemens Healthineers is currently working with the US CDC to potentially establish a threshold antibody level of protection. Further work is also needed to harmonise serological tests for use on a mass scale.