April 25, 2023
Keio University School of Medicine
A research team from the Keio University School of Medicine's Department of Laboratory Medicine and Department of Preventive Medicine and Public Health has developed a mathematical model to predict the gradual decline in antibody titers against COVID-19 after vaccination. This model is based on data from a clinical study investigating the effects of COVID-19 vaccination on faculty and staff of the School of Medicine and Keio University Hospital.
From March to April 2021, Keio University Hospital administered priority vaccinations with the Pfizer COVID-19 vaccine for healthcare workers. The research team measured COVID-19 antibody titers, which are known to increase with vaccination, in 673 faculty and staff members from the School of Medicine and the hospital who had consented to participate in the study before the priority vaccinations began. Measurements were taken before vaccination and at 3 weeks, 8 weeks, 3 months, and 6 months after the second dose.
Based on the time-course antibody titer data obtained in this study, a mathematical model was devised to simulate the decay of antibody titers. This model was able to predict future antibody titers with 97% accuracy from a single antibody titer measurement taken after two vaccine doses. Furthermore, when validated with data from staff at the National Hospital Organization Mie National Hospital and dialysis patients at facilities participating in the Japanese Society for Dialysis Therapy, the model demonstrated high predictive accuracy of 98.2% and 83.3%, respectively.
The team plans to further develop the model to predict long-term fluctuations in antibody titers. This is expected to enable easy prediction of future antibody levels from a single measurement, which will be useful for countermeasures against emerging infectious diseases, including COVID-19.
A paper on this research was published in the journal npj Vaccines on March 7, 2023 (JST).
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