Updated COVID-19 vaccines continue to offer strong protection, research shows

Updated COVID-19 vaccines are still providing effective protection against infection, emergency department visits, hospitalization and death, according to new research published today in JAMA Internal Medicine.

Data in this new study shows that the 2024-2025 COVID-19 vaccines provide similar protection to the previous formulation. They were found to be most protective four weeks after vaccination, providing 44.7% effectiveness against infection, 45.1% effectiveness against emergency department visits, and 57.5% effectiveness against hospitalization or death.

Protection against each outcome waned over time, declining at 10 weeks after vaccination to 35.5% effectiveness against infection, 42.9% effectiveness against emergency department visits, and 49.7% effectiveness against hospitalization or death. At 20 weeks, protection dropped to 16.7% effectiveness against infection, 39.1% effectiveness against emergency department visits, and 34.0% effectiveness against hospitalization or death.

Comparisons between different Omicron subvariants showed similar effectiveness.

Danyu Lin, PhD, Dennis Gillings Distinguished Professor in the Department of Biostatistics at the Gillings School, is lead author on the study. Additional co-authors include Yi Du, PhD, and Sai Paritala, PharmD, from the Nebraska Department of Health and Human Services; Yangjianchen Xu from the University of Waterloo; and Patrick Maloney, PhD, from the University of Nebraska Medical Center.

COVID-19 is still causing a lot of serious illness. Our study showed that the 2024-2025 COVID-19 vaccines were effective, especially against severe outcomes, although their effectiveness waned over time. Thus, it is beneficial to have an annual COVID-19 vaccination, particularly for individuals at high risk of severe outcomes. Our study also showed that vaccine effectiveness was similar against different Omicron subvariants. Thus, the 2025-2026 vaccines, which target similar omicron subvariants as the 2024-2025 vaccines did, will likely have similar effectiveness."

Danyu Lin, PhD, Dennis Gillings Distinguished Professor, Department of Biostatistics, Gillings School

COVID-19 vaccines are available to most Americans 65 years and older, as well as those between ages 18-64 with health conditions that put them at higher risk of severe illness from COVID-19. Some of these conditions include asthma, diabetes, obesity, pregnancy, heart conditions, cancer and smoking (current or former). For the full list, please visit the Centers for Disease Control and Prevention's website.

In North Carolina, vaccines are available without a prescription for those who qualify at pharmacies across the state, according to the N.C. Department of Health and Human Services.