Use and Effectiveness of COVID-19 Vaccines Using State Vaccine Registries and Insurance Claims Data

The vaccine effectiveness (VE) of BNT162b2 COVID-19 vaccine (e.g. KP.2 monovalent formulation) in preventing post-COVID health conditions will be assessed (Aim 1). This aim will utilize a retrospective cohort time-to-event design and evaluate the VE among vaccine-eligible patients from when the vaccine was authorized or approved (specified by age group) through the most current data available. Patients will be sourced from HealthVerity and includes patients who are enrolled in the claims database; data from the state's deidentified vaccine registry will be used to supplement claims data. Patients who will be followed for the PCC endpoint must be eligible to receive the vaccine during the study period. Comparisons between the vaccinated and vaccine eligible but unvaccinated (i.e., no receipt of the most recent formulation) groups will be made using descriptive statistics, incidence rates, and hazard ratios. The second part of the study (Aim 2) will use a retrospective cohort design to describe the uptake of the vaccine in specific groups over time. Subjects will be identified through three different methods: 1) by analyzing all available dosing records in the Immunization Registry, 2) by using HealthVerity claims data based on specific calendar time periods when the vaccine was available, or 3) based on the start of pregnancy that occurs after EUA date. Patients will be followed until experiencing the vaccination under study, disenrollment, end of data or death. Vaccinations will be assessed overall and also by specific type of prior dose (mRNA vs other).