The landscape of childhood vaccinations has shifted with recent changes announced by the Department of Health and Human Services (HHS). A significant revision cuts the number of vaccines universally recommended for children from 17 to 11. While the human papillomavirus (HPV) vaccine remains recommended for all children, a key change involves a reduction in the number of doses needed for protection.
Currently, guidelines suggest that individuals receive one dose of the HPV vaccine, a departure from the previous recommendations of two or three doses depending on the age of initiation. This shift is rooted in evolving scientific understanding and data from recent trials.
The evolution of HPV vaccination schedules began with a three-dose regimen. Research subsequently demonstrated that two doses provided comparable efficacy, leading to updated recommendations from organizations like the World Health Organization and the Centers for Disease Control and Prevention (CDC). Now, emerging evidence suggests that even a single dose may be sufficient to confer robust protection.
This latest recommendation stems from the ESCUDDO trial, a study published in the New England Journal of Medicine in December 2025. The trial, conducted in Costa Rica, enrolled over 20,000 girls aged 12 to 16 between November 2017 and February 2020. Participants were randomly assigned to receive either one or two doses of either Cervarix or Gardasil 9.
The study revealed that all four vaccination groups – those receiving one or two doses of Cervarix and those receiving one or two doses of Gardasil 9 – demonstrated over 97% effectiveness. Researchers concluded that a single dose of the vaccine was as effective as two doses in protecting against HPV types 16 and 18, which are responsible for approximately 70% of cervical cancers. Gardasil 9 offers protection against these types, as well as seven additional HPV types linked to genital warts and other cancers, including those of the vulva, vagina, penis and anus.
A similar randomized trial conducted in Kenya yielded comparable results, showing 98% effectiveness with a single dose of either Gardasil 9 or Cervarix in preventing infection with HPV types 16 and 18.
The potential benefits of transitioning to a single-dose HPV vaccine regimen are substantial. It could lead to increased vaccine uptake by removing logistical barriers such as the need for multiple appointments and associated costs, including transportation and time off work. This simplification would also facilitate large-scale vaccination efforts, particularly in resource-limited settings.
However, the American Academy of Pediatrics (AAP) has not yet altered its recommendations. This discrepancy has raised concerns about potential confusion among healthcare providers and parents, as many pediatricians rely on AAP guidance for vaccination protocols.
the manner in which these changes were implemented has drawn scrutiny. The HHS decision was made without the customary involvement of an advisory committee and public comment period, raising questions about transparency and the standard process for updating vaccine schedules.
It’s important to note that not all of the changes to the vaccine schedule announced by HHS were based on scientific evidence, adding to the concerns surrounding the process. Health officials recommend that parents consult with their pediatrician to determine the most appropriate vaccination schedule for their children, taking into account individual risk factors and the latest scientific guidance.
The move towards a single-dose HPV vaccine represents a significant development in preventative healthcare. While the long-term implications are still being evaluated, the initial data suggest a promising path towards more accessible and effective HPV vaccination programs. Continued monitoring and research will be crucial to ensure the ongoing safety and efficacy of this revised approach.
