Quantifying the impact of SARS-CoV-2 temporal vaccination trends and disparities on disease control
Sophie L. Larsen, Ikgyu Shin, Jefrin Joseph, Haylee West, Rafael Anorga, Gonzalo E. Mena, Ayesha S. Mahmud, and
Pamela P. Martinez SARS-CoV-2 vaccines have been distributed at unprecedented speed. Still, little is known about temporal vaccination trends, their association with socioeconomic inequality, and their consequences for disease control. Using data from 161 countries/territories and 58 states, we examined vaccination rates across high and low socioeconomic status (SES), showing that disparities in coverage exist at national and subnational levels. We also identified two distinct vaccination trends: a rapid initial rollout, quickly reaching a plateau, or sigmoidal and slow to begin. Informed by these patterns, we implemented an SES-stratified mechanistic model, finding profound differences in mortality and incidence across these two vaccination types. Timing of initial rollout affects disease outcomes more substantially than final coverage or degree of SES disparity. Unexpectedly, timing is not associated with wealth inequality or GDP per capita. While socioeconomic disparity should be addressed, accelerating initial rollout for all over focusing on increasing coverage is an accessible intervention that could minimize the burden of disease across socioeconomic groups. Speeding up vaccine rollout for all socioeconomic groups surpasses the impact of eliminating disparity or increasing coverage.