Prevalence of Human Papillomavirus Genotypes in Unvaccinated 16- to 20-Year-Old Men in Quebec, Canada
Bibliographic record
Abstract
BACKGROUND: Since 2008, Quebec (Canada) has had a school-based human papillomavirus (HPV) vaccination program achieving >90% coverage (≥ 1 dose) in girls by age 15. In 2018, Quebec was the first jurisdiction to switch to a mixed schedule (nonavalent + bivalent), and as such wanted to evaluate it. However, when devising an evaluation strategy for new vaccine schedules, the presence of herd effect needs to be ascertained. With this in mind, this study aimed to measure HPV prevalence among unvaccinated 16- to 20-year-old sexually active men. METHODS: In 2020-2022, men were recruited from schools and online across the province of Quebec. Participants completed an online questionnaire and provided a self-collected penile swab (surface) for HPV detection and genotyping (Anyplex II-HPV28 Detection assay). Risk factors associated with HPV positivity were assessed. Vaccination status (unvaccinated) was verified through the Quebec Vaccination Registry. RESULTS: Overall, 369 participants provided a sample suitable for HPV testing. HPV prevalence was 18.4% (95% confidence interval [CI], 14.6%-22.8%). Only 2 participants harbored a quadrivalent (4vHPV)-targeted genotype (0.5% [95% CI, .1%-1.9%]), both of whom reported sexual contact with men. In multivariate analysis, age, greater number of lifetime sexual partners, and history of other sexually transmitted infections were independently associated with positivity for at least 1 HPV genotype. CONCLUSIONS: The low 4vHPV-targeted genotype prevalence (<1%) among unvaccinated men of the same age as women vaccinated with 4vHPV suggests a strong herd immunity among young adults in Quebec. Evaluation of schedule changes will have to take this finding into account. Clinical Trials Registration. NCT04297670.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".