Skip to main content

Advanced Search

Advanced Search

Current Filters

Filter your query

Categories

Publication Types

Other

Area of Focus
Topics
Date Range
to

Area of Focus

Improving Health Care Quality

Blog

/

How Many COVID-19 Hospitalizations and Deaths Can Be Averted if States Immediately Accelerate Their Vaccination Efforts?

Outreach volunteers knock on a door to inform residents about an upcoming COVID-19 vaccination event

Outreach volunteers knock on a door to inform residents about an upcoming COVID-19 vaccination event on June 30, 2021, in Birmingham, Ala. Alabama and several southern states have among the lowest vaccination rates in the country. Photo by Elijah Nouvelage/AFP via Getty Images

Outreach volunteers knock on a door to inform residents about an upcoming COVID-19 vaccination event on June 30, 2021, in Birmingham, Ala. Alabama and several southern states have among the lowest vaccination rates in the country. Photo by Elijah Nouvelage/AFP via Getty Images

In July, the highly contagious Delta variant of SARS-CoV-2 kindled another wave of hospitalizations and deaths in several U.S. states. Most of these tragically preventable events occurred among unvaccinated adults, but the toll also includes an increasing number of children. Unvaccinated individuals face a fivefold higher rate of infection and a 29 times higher hospitalization risk than their vaccinated counterparts.

Nationally, new COVID-19 cases surged near the end of August to a seven-day average of 160,000 per day. But during September, several southern states that were hit hard during July and August started to see infections and hospitalizations ebb while other states with lower rates during the summer began to see rates pick up. The percentage of population vaccinated varies substantially among states. In some, nearly 70 percent of the population have been fully vaccinated while others have only recently achieved 40 percent. Despite the ongoing Delta wave and the imminent threat of new regional outbreaks, the pace of vaccination slowed recently to fewer than 700,000 doses per day; this could leave millions vulnerable for many months and add to the occurrence of preventable hospitalizations and deaths.

What would happen if we significantly accelerated the pace of vaccination? To forecast the impact during the next six months, we used a previously developed simulation model of COVID-19 transmission dynamics. We considered five southern states that are currently in a declining trend, past their peak number of infections in early September (Alabama, Florida, Georgia, Louisiana, and Texas) and five northern states with an upward trend in infections at the end of September (Michigan, New Hampshire, New York, Pennsylvania, and Wisconsin). We simulated a scenario in which each state would increase the daily number of vaccine doses delivered by 50 percent above their pace during the last week of August 2021. We compared that to a status quo scenario under which vaccinations continued at the August pace.

The model predicts that through the end of March 2022, increasing daily COVID-19 vaccination by 50 percent starting in September would prevent a total of approximately 19,500 hospitalizations and 6,900 deaths across the 10 states studied. The total number of estimated hospitalizations potentially averted by the end of March 2022 ranges from 65 in New Hampshire to 5,056 in Texas. The total number of estimated deaths potentially averted ranges from 10 in New Hampshire to 1,441 in Florida.

Our results reveal several insights. First, if daily vaccination is increased immediately by 50 percent, a substantial number of infections, hospitalizations, and deaths can be prevented. Second, even states that are starting to see declines in daily hospitalizations and deaths (such as Alabama, Florida, Georgia, and Louisiana) can still benefit from accelerating the pace of vaccination now. With low rates of vaccination and persistent spread of the virus, unvaccinated people in these states remain at especially high risk. Third, increasing vaccination rates now may blunt a potential fall or winter surge in hospitalization and deaths in upper Midwestern and Northeastern states as people spend more time indoors.

Is a 50 percent increase in daily vaccination attainable? It is certainly possible, as all states achieved a faster pace earlier in their vaccination rollout at a time when supply was limited. To the extent that hesitancy is a barrier, vaccine mandates recently instituted by employers, schools, and businesses appear to have motivated many workers, students, and consumers to accept vaccination, as long as deadlines, expectations, and penalties are clear.

There are reasons for states to act now. Preventable hospitalizations and deaths place a heavy burden on families, caregivers, and the health care workforce. Hospital care is expensive, not just for people who are underinsured, but for federal and state insurance programs that cover the costs, with much of it borne by taxpayers. With COVID-19 restrictions lifted, hospital and health care workforce capacity will be needed to cope with other urgent health demands, such as traumatic injury, chronic disease, seasonal influenza, and other respiratory viruses. The number of people with long COVID will grow as new infections continue, adding to the burden of chronic disease and the costs of care for years to come.

Our results may understate the impact of accelerated vaccination. We assumed that the landscape of SARS-CoV-2 variants will remain unchanged for the next several months. Viral evolution may instead produce new variants that are even more contagious. Reaching higher levels of vaccination quickly can reduce the risk posed by new variants.

Vaccines against COVID-19 have proven to be highly effective and safe. By the end of September, more than 210 million Americans age 12 and older had received at least one dose; more than 180 million have been fully vaccinated. However, with only 56 percent of the population fully vaccinated, millions may still be at risk of severe illness, hospitalization, or death if they become infected with SARS-CoV-2. The U.S. has ample supply, but its vaccination rate ranks last among the world’s seven wealthiest large democracies. Vaccination works best as prevention. Quickly increasing population immunity now can prevent needless COVID-19 hospitalizations and deaths while keeping hospital beds open and staffed for people with other serious health problems.

How We Conducted This Study

We expanded our age-stratified, agent-based model of COVID-19 to simulate the spread SARS-CoV-2 variants, including Alpha, Gamma, Iota, and Delta variants in addition to the original Wuhan-1 strain. The model parameters included the population demographics of the 10 states studied here, disease characteristics and estimates of variant transmissibility, and age-specific risks of severe health outcomes because of COVID-19. We retrieved data on daily vaccine doses from the Centers for Disease Control and Prevention in each state. Vaccine effectiveness against infection, symptomatic, and severe disease were derived from published studies, accounting for different vaccine types, each variant, and timelines for generation of immunity after first and second doses. We calibrated the model to reported incidence in each state between Oct. 1, 2020, and August 31, 2021, and simulated the scenarios to project the impact of vaccination from September 1, 2021, to March 31, 2022. Through stochastic Monte Carlo simulations, we derived estimates of infections, hospitalizations, and deaths projected to occur within the study period for the two scenarios: 1) daily vaccination rate remained the same as what was achieved in each of the 10 states during the last week of August 2021 (status quo), and 2) daily vaccination rate increased by 50 percent compared to the status quo. We then calculated mean estimated and 95 percent credible intervals using a bias-corrected and accelerated bootstrap method. For additional information on the model, please contact the authors.

Publication Details

Date

Contact

Eric C. Schneider, Senior Vice President for Policy and Research, The Commonwealth Fund

[email protected]

Citation

Eric C Schneider et al., “How Many COVID-19 Hospitalizations and Deaths Can Be Averted if States Immediately Accelerate Their Vaccination Efforts?,” To the Point (blog), Commonwealth Fund, Oct. 5, 2021. https://doi.org/10.26099/xm9p-7f94