OBJECTIVE: In February 2023, the French government announced the generalization of vaccination against human papillomavirus (HPV) infections for all voluntary 5th graders free of charge. Regional Health Agency and Reunion's rectorate asked two practitioners to run a training course on HPV, for principal education advisors, science and earth life teachers, and school nurses/doctors of all Reunion's middle schools. METHODS: Our aim was to assess the impact of this training on knowledge and acceptability of HPV vaccination among middle school staff. A first questionnaire (Q1) was filled in by participants during the training course, a second (Q2) at the immediate end of the course and a third (Q3) 2 months later, at the start of the new school year. RESULTS: In Q1, 198 respondants obtained 45.1% of good answers, in Q2, there were 83.5% of good answers among 58 respondants and in Q3, 59.7% for 27 respondants. HPV vaccination training improved the knowledge of middle school staff, but the knowledge score decreased over time. In addition, middle-school staff seemed to be generally in favor of HPV vaccination. But their intention to have their own children (or future children) vaccinated seemed to decrease over time, at a distance from the training (80.7% at time of Q2 and 66.7% at Q3). CONCLUSION: Regular refresher courses seem necessary to maintain knowledge levels and motivation in vaccination intention.