Vaccination Trends and their Relationship to Continuity of Care in a US-Based Primary Care Practice Registry

Primary care has long played an important role in vaccination in the US and around the world. However, the COVID-19 pandemic disrupted conventional administration patterns for many vaccines, in part through an increased emphasis on mass vaccination sites and pharmacies as a way to expedite the rollout of the COVID vaccine. In an era of increased vaccine hesitancy, though, the frequency of long-term, trusting relationships between patients and their primary care providers may bolster diminishing adherence to recommended vaccine schedules. In this study, we used the American Family Cohort - the USs largest primary care clinical registry - to assess how patterns of vaccination in primary care have changed since 2017 for ten vaccines recommended on the basis of age. We also assessed how these trends have changed among practices with varying rates of care continuity to test our hypothesis that an ongoing patient-provider relationship improves vaccination rates. In a total of 61,766,185 visits for 6,943,589 patients conducted at 1,323 practices, we observed that the influenza vaccine was the most commonly administered vaccine, followed by pneumococcus. The rates of many vaccines peaked in 2019, though, mirroring national trends that suggest few vaccines are administered at the same rates as they were post-pandemic. We found little support for our hypothesis that care continuity is related to vaccination rates. The population health impact of payment policies and commercial initiatives that shift vaccine administration out of primary care is unclear at this point, but merits ongoing surveillance.