Minimizing Loss of Life in COVID-19 in a 100 Day Period in the U.S.A. by Personalized-Dose Vaccination

Abstract

Background: We aimed at minimizing loss of lives in the COVID-19 pandemic in the USA by identifying optimal vaccination strategies during a 100-day period with limited vaccine supplies. While lethality is highest in the elderly, transmission and case numbers are highest in the younger. A strategy of first vaccinating the elderly is widely used, thought to protect the vulnerable, elderly best. Despite lower immunogenicity in the elderly, mRNA vaccines retain high efficacy, implying that in the younger, reduced vaccine doses might suffice, thereby increasing vaccination counts with a given vaccine supply. Methods: Using published immunogenicity data of the Moderna mRNA-1273 vaccine, we examined the value of personalized-dose vaccination strategies, using a modeling approach incorporating age-related vaccine immunogenicity, social contact patterns, population structure, COVID-19 case and death rates in the USA in late January 2021. An increase if the number of persons that can be vaccinated and a potential reduction of the individual protective efficacy was accounted for. Results: Age-personalized dosing strategies reduced cases faster, shortening the pandemic, reducing the delay to reaching Conclusion: Rapid reduction of COVID-19 case and death rate in the USA in 100 days with a limited vaccine supply is best achieved when personalized, age-tailored dosing for highly effective vaccines is used, according to this vaccination strategy model parameterized to U.S. demographics, COVID-19 transmission and vaccine characteristics. Protecting the vulnerable is most effectively achieved by personalized-dose vaccination of all population segments, while an “elderly first” approach costs more lives, even in the elderly.