HPV vaccine and cancer prevention
Romanes for Uganda, Wheelchair Rugby Mission in Africa
27th June 2025
Inequalities and territorial disparities in Italy
12 July 2025
Numerous studies conducted in the United States demonstrate that the Vaccine against papillomavirus human (HPV) offers effective and long-lasting protection against infections and related cancers.
The data collected by the Centers for Disease Control and Prevention (CDCs) in fact show a drastic decline (-90%) of infections by oncogenic strains, among vaccinated adolescents (Centers for Disease Control and Prevention.
Infections are also significantly reduced (-74%) in unvaccinated girls in the USA, due to the so-called 'herd immunity' (CDCs, 2022). In Italy, on the other hand, vaccination coverage is still far from the objectives.
HPV and Cervical Cancer, US Data
The high vaccination coverage – equal to 78,5% in 2021 among girls – contributed to a significant reduction in incidence in the USA of precancerous cervical lesions in young women:
- the precursors of the serious injuries have decreased dramatically, -80% between 2008 and 2022, in women aged 20 to 24 (CDC, 2022);
- i deaths for cervical cancer in women under-25 dropped from 55 cases in the three-year period 1992-1994 to 35 in 2013-2015, down to just 13 cases in 2019-2021 (US Cancer Statistics Working Group.
Clinical efficacy
Randomized, controlled clinical studies have shown avaccine efficacy between 92% and 100% in preventing HPV 16 and 18 infections, as well as cervical lesions of grade 2 or higher (CIN2+), among previously uninfected young women (Drolet et al., 2019; Lei et al., 2020).
Favorable results – in the reduction of genital warts and HPV-related anogenital lesions – were also observed in teenage males (Garland et al., 2016). An element worthy of attention, as we will see, under several aspects.
Vaccination in males
Major international health agencies – including WHO, CDC and ECDC (European Center for Disease Control and Prevention) – recommend the universal vaccination, including for males, ideally to be administered before the onset of sexual activity (World Health Organization, 2020; CDC, 2022).
La vaccination anti-HPV in males in fact, it represents an important individual and collective prevention tool, both to reduce the transmission of the virus and to prevent tumors and lesions affecting the anogenital system and the oral cavity, which are increasing especially among adult males (Chaturvedi et al., 2011).
The quadrivalent and nonavalent vaccine have in fact proven to be highly effective in the prevention of genital warts and high-grade anal intraepithelial lesions in males (Giuliano et al., 2011; Garland et al., 2016).
The importance of vaccination even in adulthood
Although HPV vaccination is most effective when administered before the onset of sexual activity, a growing body of evidence indicates significant benefits for adults as well, especially if not previously exposed to oncogenic strains of the virus. FDA (Food and Drug Administration) and the CDCs in the USA approve the use of the vaccine up to the age of forty-five, and clinical studies demonstrate that in adults it can reduce the probability of persistent infection, condylomas and precancerous lesions (Castellsagué et al., 2011; Joura et al., 2015).
Although efficacy tends to decrease with increasing age and previous sexual experience, vaccination can still offer individual protection and contribute to the reduction of viral circulation, especially in high-risk groups. Furthermore, recent data show that many adults have never been exposed to all the strains included in the nine-valent vaccine, leaving room for effective secondary prevention (Petrosky et al., 2015).
Is one dose enough?
Recent evidence suggests that even a single dose of HPV vaccine could offer protection comparable to that guaranteed by the full cycle. A large observational study conducted in Kenya showed an 88,9% reduction in persistent oncogenic HPV infections with a single administration (Barnabas et al., 2022). This approach could facilitate vaccination coverage in low-adherence settings.
It is important to underline, however, that almost all randomized clinical trials and analyses on cancer prevention are based on complete vaccination schedules, consisting of two or three doses. For this reason, the systematic adoption of a single-dose regimen – although it represents a promising strategy in low-coverage settings – requires further scientific confirmation and evaluation by health authorities.
The HPV vaccine in Italy: current status and potential
The World Health Organization (OMS) promotes a global campaign to eliminate cervical cancer as a public health problem, aiming to vaccinate 90% of girls by age 15 (World Health Organization.
In Italy, a nonavalent vaccine is available, which protects against 9 oncogenic strains and can prevent up to 90% of HPV-related tumors. However, coverage across the country remains uneven between regions, and in some areas it is far from the desired goal (Da Rold, 2025).
Long-term prospects and benefits
La protection è maxim when the vaccine is administered at an early age, ideally between nine and fourteen years of age, with the ability to prevent up to ninety-nine percent of precancerous lesions caused by oncogenic strains 16 and 18 (Lei et al., 2020).
Studies of follow-up long-term confirm that the vaccine's efficacy remains stable for at least ten years without the need for a booster (Markowitz et al., 2018).
The high vaccination coverage in the target population also favors a herd effect, offering indirect protection even to those who have not been vaccinated, thanks to the reduced circulation of high-risk strains (Drolet et al., 2019).
Provisional conclusions
The efficacy of the HPV vaccine is now confirmed by solid epidemiological data and large-scale clinical studies. In fact, this vaccination:
- dramatically reduces the incidence of infections and precancerous lesions, even with incomplete coverage,
- could guarantee high protection with just one dose;
- protects women and men from numerous types of cancer, including oropharyngeal and anal cancers;
- offers long-term defense, with an appreciable safety profile.
However, to maximize the impact in Italy it is essential to:
- increase early vaccination coverage, involving schools and families;
- evaluate simplified administration schedules;
- strengthen public communication, countering vaccine resistance in this specific area.
Dario Dongo
Cover art copyright © 2025 Dario Dongo (AI-assisted creation)
References
- Barnabas, R. V., Brown, E. R., Onono, M. A., Bukusi, E. A., Njoroge, B., Winer, R. L., … & Mugo, N. R. (2022). Efficacy of single-dose human papillomavirus vaccination among young African women. NEJM Evidence, 1(10), EVIDoa2100056. https://doi.org/10.1056/EVIDoa2100056
- Castellsagué, End-of-study safety, immunogenicity, and efficacy of quadrivalent HPV (types 2011, 6, 11, 16) recombinant vaccine in adult women aged 18–24 years. British Journal of Cancer, 105 (1), 28–37. https://doi.org/10.1038/bjc.2011.185
- Centers for Disease Control and Prevention. (2022). Human Papillomavirus (HPV) vaccination coverage among adolescents aged 13–17 years — United States, 2021. Morbidity and Mortality Weekly Report, 71 (33), 1055–1062. https://doi.org/10.15585/mmwr.mm7135a1
- From Rold, C. (2025, July 2). US data suggests HPV vaccine works very well. AIRC (Italian Association for Cancer Research). https://www.airc.it/news/dati-statunitensi-suggeriscono-che-il-vaccino-contro-lhpv-funziona-molto-bene
- Drolet, M., Bénard, É., Pérez, N., Brisson, M., & HPV Vaccination Impact Study Group. (2019). Population-level impact and herd effects following the introduction of human papillomavirus vaccination programmes: updated systematic review and meta-analysis. The Lancet, 394 (10197), 497–509. https://doi.org/10.1016/S0140-6736(19)30298-3
- Garland, S. M., Kjaer, S. K., Muñoz, N., Block, S. L., Brown, D. R., DiNubile, M. J., … & Joura, E. A. (2016). Impact and effectiveness of the quadrivalent human papillomavirus vaccine: a systematic review of 10 years of real-world experience. Clinical Infectious Diseases, 63 (4), 519–527. https://doi.org/10.1093/cid/ciw354
- Joura, E.A., Giuliano, A.R., Iversen, O.E., Bouchard, C., Mao, C., Mehlsen, J., … & Broad Spectrum HPV Vaccine Study Group. (2015). A 9-valent HPV vaccine against infection and intraepithelial neoplasia in women. New England Journal of Medicine, 372 (8), 711–723. https://doi.org/10.1056/NEJMoa1405044
- Lei, J., Ploner, A., Elfström, K. M., Wang, J., Roth, A., Fang, F., … & Sparén, P. (2020). HPV vaccination and the risk of invasive cervical cancer. New England Journal of Medicine, 383 (14), 1340–1348. https://doi.org/10.1056/NEJMoa1917338
- Markowitz, L. E., Gee, J., & Chesson, H. (2018). Ten years of human papillomavirus vaccination in the United States. Academic Pediatrics, 18(2), S3–S10. https://doi.org/10.1016/j.acap.2017.09.014
- Petrosky, E., Bocchini, J. A., Hariri, S., Chesson, H., Curtis, C. R., Saraiya, M., … & Markowitz, L. E. (2015). Use of 9-valent human papillomavirus (HPV) vaccine: Updated HPV vaccination recommendations of the Advisory Committee on Immunization Practices. Morbidity and Mortality Weekly Report, 64 (11), 300–304. https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6411a3.htm
- US Cancer Statistics Working Group. (2023). United States cancer statistics: 1999–2021 incidence and mortality web-based report. US Department of Health and Human Services, Centers for Disease Control and Prevention and National Cancer Institute. https://www.cdc.gov/cancer/uscs/index.htm
- World Health Organization. (2020). Global strategy to accelerate the elimination of cervical cancer as a public health problem. ISBN: 9789240014107. Geneva: WHO. https://www.who.int/publications/i/item/9789240014107
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
