In the summer of 2019, the U.S. Advisory Committee on Immunization Practices (ACIP) updated its recommendations for HPV vaccination. The new recommendation regarding adults ages 27-45y (i.e., mid-adults) indicated that a "shared clinical decision-making" (SCDM) approach, rather than a routine recommendation, should be used. The Morbidity and Mortality Weekly Report (MMWR) publication that described this SCDM recommendation included specific conditional guidance and considerations for SCDM. However, some aspects of the guidance are vague, and others are inconsistent with SCDM, which could lead to confusion for adult health care providers and ultimately lead to under-vaccination of eligible individuals who would benefit from HPV vaccination. More recently, in the U.S. there have been policy proposals to shift additional vaccine recommendations from routine to SCDM. In this commentary, we briefly outline the ACIP recommendations, provide a clear overview of SCDM, and then offer potential implementation challenges for this guideline. For both unvaccinated adult patients and the providers who serve them, clear guidance on effective SCDM practices for HPV vaccination is an essential component for addressing the prevention of HPV-related disease. Using the context of mid-adult HPV vaccination, we also discuss the implications of SCDM recommendations for other vaccines.

Test negative design studies allow for COVID-19 vaccine effectiveness (VE) estimation while minimizing selection bias from healthcare seeking and testing practices. However, failure to consider correlation between vaccination behaviors may result in biased COVID-19 VE estimates. Using different methods to account for potential correlation between COVID-19, influenza, and respiratory syncytial virus (RSV) vaccination status, we investigated variability in VE estimates of the 2023-2024 COVID-19 vaccine against COVID-19-associated emergency department and urgent care (ED/UC) encounters and hospitalizations during the 2023-2024 respiratory virus season. Data were leveraged from VISION, an electronic health record-based platform. VE estimates ≥7 days post vaccination did not increase by more than 5 percentage points against ED/UC encounters and 3 percentage points against hospitalizations when accounting for influenza and RSV vaccination status or excluding influenza and RSV positive controls. As the magnitude of this influence depends on season-specific factors, ongoing monitoring is warranted.

Human papillomavirus (HPV) vaccination is a key strategy for preventing HPV-related cancers, yet series completion among U.S. adolescents remains below national public health goals. This study analyzed nationally representative data from the 2021-2023 National Immunization Survey-Teen (NIS-Teen) to describe recent patterns in HPV vaccination initiation and completion among adolescents aged 13-17 years. Complex survey-weighted analyses estimated the proportion of adolescents who had not initiated HPV vaccination, had initiated but not completed the series, or had completed the series based on provider-verified vaccination records and Advisory Committee on Immunization Practices (ACIP) age-specific dose recommendations. The analytic sample included 126,226 adolescents. Weighted estimates indicated that 39.8% were aged 13-14 years and 60.2% were aged 15-17 years; 51.2% were male and 48.8% female. HPV vaccine series completion remained stable across survey years, with completion estimates of 62.4% in 2021, 63.9% in 2022, and 62.5% in 2023. Initiation without completion ranged from 14.4% to 15.2%, while non-initiation ranged from 21.7% to 22.9%. Across all years, completion was consistently higher among older adolescents and females compared with younger adolescents and males. Despite modest gains in initiation, HPV vaccination coverage remained relatively stable during the study period. This stability, observed during the COVID-19 recovery period, may reflect preservation of uptake rather than true stagnation. These findings highlight the need for strategies emphasizing early vaccination, strong provider recommendations, and reminder-based follow-up to improve series completion and advance national immunization targets.