Strategies for vaccination against SARS-CoV-2 to efficiently bring R<1

Voigt, A.; Omholt, S. W.; Almaas, E.

With limited availability of vaccines, an efficient use of the limited supply of vaccines in order to achieve herd immunity will be an important tool to combat the wide-spread prevalence of COVID-19. Here, we propose a targeted vaccination approach (EHR) that provides a significant reduction in the necessary number of doses needed achieve herd immunity compared to age-prioritized and random selection vaccination schemes. Using high-fidelity individual-based computer simulations with Oslo, Norway as an example, we find that for a community reproductive number in a setting where R=1.4 without population immunity, the EHR method reaches herd immunity at only 15% of the population vaccinated, whereas the common age-prioritized approach needs 40%. With R=1.9 in the absence of immunity, EHR needs 30% and age-prioritized needs 52%.