Study Reveals Critical Gaps in Measles Vaccination Knowledge Among ER Patients

Measles Outbreaks Drive Urgent Research into Vaccination Gaps

Measles remains one of the most contagious infectious diseases, primarily spread through coughing and sneezing. Even minor declines in vaccination coverage can trigger outbreaks. As of 2026, California has reported its highest annual measles case count in seven years, underscoring the urgency of addressing vaccination gaps.

UC Riverside-Led Study Exposes Critical Knowledge and Coverage Gaps

A new study led by researchers at the University of California, Riverside has identified significant deficiencies in measles-related knowledge, vaccination status, and acceptance of the MMR vaccine (measles, mumps, and rubella) among patients visiting emergency departments across the United States. Published in the American Journal of Emergency Medicine, the research examines how misinformation and systemic barriers contribute to declining vaccination rates amid ongoing measles outbreaks.

“We found that a substantial portion of emergency department patients lack accurate knowledge about measles and the MMR vaccine. Many participants were either unsure of their vaccination status or reported not receiving the vaccine at all. Additionally, vaccine hesitancy, driven by misconceptions about safety and necessity, remains a persistent issue.”

Alexandra Eftimie, medical student and co-lead author of the study

Survey Reveals Disparities in Vaccination Access and Knowledge

The study analyzed survey data collected between April and December 2024 from 2,459 adult patients across ten U.S. emergency departments. Researchers evaluated MMR vaccination status, knowledge levels, and willingness to receive the vaccine among a diverse population.

“We identified key disparities in under-vaccination associated with factors such as race, language, insurance status, and access to primary care. These disparities specifically emphasized how systemic barriers shape both access to vaccines and health literacy among diverse populations.”

Sahithi Malireddy, undergraduate neuroscience student and co-lead author

Emergency Departments as Critical Points for Public Health Intervention

The researchers emphasize that emergency departments can serve as vital “safety net” points of care for underserved populations who face barriers to accessing vaccines and healthcare through traditional channels. Their findings suggest that emergency departments can play a pivotal role in delivering accessible, evidence-based public health interventions to improve vaccine equity.

“This really offers health care systems an opportunity to leverage emergency departments not only for emergent care, but also as spaces to deliver accessible, evidence-based public health interventions and improve vaccine equity. By leveraging emergency departments as points of intervention, health care systems may be able to reach individuals who would otherwise fall through the cracks of preventive care.”

Sahithi Malireddy

Systemic Barriers Exacerbate Vaccination Gaps

The study highlights how systemic barriers—such as limited literacy tools, language differences, insurance challenges, and stigma—contribute to gaps in vaccination knowledge and access. Researchers note that these barriers shift the focus from individual misunderstanding to structural inequities, emphasizing the need for healthcare systems to make knowledge accessible and actionable for marginalized communities.

“Many gaps stem from systemic barriers like limited literacy tools, language differences, insurance issues, and stigma. They show how culture and access shape responses to symptoms, shifting focus from individual misunderstanding to structural inequities—and underscoring our responsibility to make healthcare knowledge accessible and actionable for marginalized communities.”

Sahithi Malireddy

Practical Steps to Improve MMR Vaccination Rates

Robert Rodriguez, senior author and professor of medicine at the UCR School of Medicine, outlines actionable steps emergency departments can take to boost MMR vaccination rates without overburdening staff or resources.

“While most emergency departments may not be able to administer MMR vaccines, they can still serve as high-impact sites for screening and education—especially for underserved populations. They can inform patients about the importance of the MMR vaccine and direct them to accessible options.”

Robert Rodriguez

Key Findings Summary

• Study Focus: Gaps in measles vaccination knowledge, status, and acceptance among ER patients.
• Data Source: Surveys from 2,459 adult patients across 10 U.S. emergency departments (April–December 2024).
• Key Disparities: Under-vaccination linked to race, language, insurance status, and primary care access.
• Systemic Barriers: Limited literacy, language differences, insurance issues, and stigma.
• Recommendations: Emergency departments should prioritize education and referrals to improve vaccine equity.