Specialized Vaccine Care for Adverse Events Following Immunization and Impact on Vaccine Hesitancy in the Military Health System.

INTRODUCTION: The World Health Organization identified vaccine hesitancy as one of the top 10 threats to global health. Vaccine hesitancy is defined as a delay in acceptance or refusal of vaccination despite the availability of vaccination services. Because vaccine safety concerns are important contributors to hesitancy, people who have experienced adverse events following immunization (AEFI) may be at especially high risk for subsequent vaccine hesitancy. The Defense Health Agency Immunization Healthcare Division (DHA IHD) provides specialized vaccine care to persons who have experienced AEFI. The impact of this specialized vaccine care on subsequent vaccine hesitancy has not been fully explored. MATERIALS AND METHODS: A cohort of patients (n= 146) was identified among those who received consultative care from DHA IHD clinicians for AEFI concerns between April 2017 and September 2022. Analyses were restricted to non-uniformed beneficiaries of the Military Health System (MHS). Uniformed beneficiaries of the MHS were excluded from this analysis since vaccination mandates preclude the use of vaccine uptake as a measure of vaccine hesitancy. Outcomes were evaluated by reviewing MHS vaccination records after initial AEFI consultation through January 2023. Vaccine acceptance was considered the inverse of hesitancy, and was defined by: (a) receipt of any subsequent vaccination, (b) receipt of seasonal influenza vaccine, (c) receipt of subsequent doses of the AEFI-associated vaccine, if clinically recommended, and (d) receipt of COVID-19 vaccine. RESULTS: A diverse group of patients with a wide range of AEFI concerns received specialized vaccine care from DHA IHD clinicians during this period. Among the cohort, 78% of patients received any subsequent vaccination, 55.2% received seasonal influenza vaccine, 57.8% received a subsequent dose of their AEFI-associated vaccine when the vaccine was clinically recommended, and 48.9% received COVID-19 vaccine. The proportion of patients who received influenza vaccine exceeded the reported rate of influenza vaccine uptake by the general population during this time period. CONCLUSION: Specialized vaccine care after AEFI concerns was associated with relatively high acceptance of subsequent vaccinations. The experiences of DHA IHD clinicians, in providing specialized vaccine care to AEFI patients, may serve as a model for other organizations that are working to reduce vaccine hesitancy, even beyond the MHS.

Overview of U.S. COVID-19 vaccine safety surveillance systems.

The U.S. COVID-19 vaccination program, which commenced in December 2020, has been instrumental in preventing morbidity and mortality from COVID-19 disease. Safety monitoring has been an essential component of the program. The federal government undertook a comprehensive and coordinated approach to implement complementary safety monitoring systems and to communicate findings in a timely and transparent way to healthcare providers, policymakers, and the public. Monitoring involved both well-established and newly developed systems that relied on both spontaneous (passive) and active surveillance methods. Clinical consultation for individual cases of adverse events following vaccination was performed, and monitoring of special populations, such as pregnant persons, was conducted. This report describes the U.S. government's COVID-19 vaccine safety monitoring systems and programs used by the Centers for Disease Control and Prevention, the U.S. Food and Drug Administration, the Department of Defense, the Department of Veterans Affairs, and the Indian Health Service. Using the adverse event of myocarditis following mRNA COVID-19 vaccination as a model, we demonstrate how the multiple, complementary monitoring systems worked to rapidly detect, assess, and verify a vaccine safety signal. In addition, longer-term follow-up was conducted to evaluate the recovery status of myocarditis cases following vaccination. Finally, the process for timely and transparent communication and dissemination of COVID-19 vaccine safety data is described, highlighting the responsiveness and robustness of the U.S. vaccine safety monitoring infrastructure during the national COVID-19 vaccination program.