Universal COVID vaccination saves lives, averts 10% to 20% of disease burden, estimates suggest
The study is timely because tomorrow, the Centers for Disease Control and Prevention’s vaccine advisory committee will discuss COVID vaccines and could further restrict their use.
A modeling study today in JAMA Network Open estimates that COVID-19 vaccination of all people in the United States in 2024-25 would have prevented 10% to 20% of hospitalizations and deaths compared with no vaccination, with additional indirect benefits to older adults compared with vaccinating only high-risk groups.
The findings come at a crucial time, after the US Food and Drug Administration (FDA) in May recommended COVID vaccines only for adults 65 and older and for people at risk for severe illness. Last month, the FDA placed major restrictions on who should receive the vaccines, notably complicating access for young children. At the time, the Infectious Diseases Society of America said the FDA’s narrowed indications put millions of American lives at risk.
Health and Human Services Secretary Robert F. Kennedy Jr. has also said healthy children and pregnant women should not receive COVID vaccination. Tomorrow, the Advisory Committee on Immunization Practices, which advises the Centers for Disease Control and Prevention (CDC), will take up COVID immunization and could further restrict vaccines.
Johns Hopkins University researchers led today’s study, which projected weekly COVID-19 hospitalizations and deaths in six scenarios of immune escape (20% to 50% per year) and vaccine recommendations (no recommendation, vaccination of at-risk people only, and vaccination for all eligible groups) from April 2024 to April 2025.
For example, under the 20% immune-escape rate, a vaccine formulated based on a variant circulating in April 2024 would be 20% less effective against symptomatic infection with a strain circulating in April 2025.
“Annually reformulated vaccines were assumed to be 75% effective against hospitalization for variants circulating on June 15, 2024, and available on September 1, 2024,” the study authors wrote. “Age- and state-specific coverage was assumed to be as reported in September 2023 to April 2024.”
Hospitalizations at low levels in all scenarios
For the 332 million US residents (estimated 58 million aged 65 years and older), COVID-19 was expected to lead to 814,000 (95% projection interval [PI], 400,000 to 1.2 million) hospitalizations and 54,000 (95% PI, 17,000 to 98,000) deaths in 2024-25, similar to the previous year.
Vaccination of high-risk groups only was projected to cut hospitalizations (compared with no vaccination) by 76,000 (95% confidence interval [CI], 34,000 to 118,000) and deaths by 7,000 (95% CI, 3,000 to 11,000) in low and high immune-escape scenarios.
Compared with vaccinating high-risk groups only, universal vaccination was predicted to provide direct and indirect benefits, preventing another 11,000 hospitalizations and 1,000 deaths in those aged 65 years and older.
In a high immune-escape scenario, the authors estimate that expanding recommendations to all ages would prevent an additional 28,000 hospitalizations and 2,000 deaths than would vaccinating high-risk groups only.
Under all scenarios, projections suggested that national COVID-19 hospitalizations would remain below the CDC threshold for low hospital admission levels (fewer than 10 weekly hospitalizations per 100,000 people) in spring 2024, followed by a rise in late summer and fall toward a winter peak, similar to or lower than the previous winter’s peak.
‘Substantial benefit’ of broader vaccination
In the high immune-escape scenarios, a projected summer peak was more pronounced. In general, weekly national hospitalization projections stayed below high CDC hospitalization levels (more than 20 weekly hospitalizations per 100,000 people) under all scenarios.
Averted COVID-19 burden due to vaccination was robust across immune escape scenarios, emphasizing the substantial benefit of broader vaccine availability for all individuals.
“Ensemble projections suggested that although vaccinating high-risk groups had substantial benefits in reducing disease burden, maintaining the vaccine recommendation for all individuals had the potential to save thousands more lives,” the researchers wrote.
“Despite divergence of projections from observed disease trends in 2024 to 2025—possibly driven by variant emergence patterns and immune escape—averted COVID-19 burden due to vaccination was robust across immune escape scenarios, emphasizing the substantial benefit of broader vaccine availability for all individuals,” they concluded.
