Modeling the effect of higher vaccination rates on the delta surge

What might this summer and fall have looked like if Florida and Texas had achieved a higher rate of vaccination against COVID-19 in adults? UF professor Burton Singer coauthored a paper, Implications of suboptimal COVID-19 vaccination in Florida and Texas, which published on Oct. 7, 2021 in The Lancet Infectious Diseases and explored this question using modeling (Singer is a member of the UF College of Liberal Arts and Sciences Department of Mathematics and the UF Emerging Pathogens Institute).

Two different line graphs compare reported deaths from COVID-19 in Florida and Texas against modeled scenarios in each state in which 74% of adults might have been vaccinated by July 31, 2021.
Figure compares reported deaths from COVID-19 in Florida (top) and Texas (bottom) against modeled scenarios in each state in which 74% of adults might have been vaccinated by July 31, 2021.

The above figure, from the paper, compares actual reported deaths from COVID-19 in Florida (top figure) and Texas (bottom figure) against modeled scenarios in each state in which 74% of adults might have been vaccinated by July 31, 2021, as in New England. Had this level of coverage been reached, many lives would have been saved.

Figure A (top) shows the daily deaths reported due to COVID-19 from Jan. 1 to Sept. 1 of this year in Florida, shown as red dots. The dark blue trend line depicts the mean estimate of their model for daily deaths, while the gray shaded area depicts the range of uncertain variability around the mean. The light blue line near the bottom projects a large difference in the rate of deaths had more adults (74% of the state’s population) been vaccinated by the end of July.

The same information is shown for Texas in Figure B, to compare the two states.

For an enlarged view of the figure, visit the paper.