New data from Denmark shows the HPV vaccine’s powerful long-term impact, while also revealing why cervical cancer screening is still essential.
A Danish study published in the journal Eurosurveillance reports that women who received the human papillomavirus vaccine in their adolescence are significantly less likely to develop human papillomavirus infections later in life.
Background
Prolonged infection with human papillomavirus (HPV) is associated with an increased risk of developing cervical cancer. Early screening and vaccination against HPV are effective strategies to prevent this cancer type.
Screening for precancerous lesions has been a widely considered strategy for secondary prevention of cervical cancer in Europe. Vaccines covering both high-risk and low-risk HPV types have been introduced as a primary preventive intervention at the end of the 2000s.
In Denmark, free public HPV vaccination (4-valent vaccine) was initially offered to all girls aged 13 to 15 in October 2008. It was later introduced to all girls turning 12 in January 2009. In November 2017, a 9-valent vaccine, which covers high-risk HPV types responsible for up to 90% of cervical cancers, was introduced in the country.
Cervical cancer screening is offered to women living in Denmark from the age of 23 years until the age of 64 years. One of the first groups of women who received the 4-valent HPV vaccination as teenage girls in 2008 reached the screening age of 23 years in 2017.
To carefully monitor screening outcomes in these vaccinated women, Trial23, a public health study embedded in the Danish national cervical screening program, was designed to determine the prevalence of HPV infection in cervical cell samples collected during three consecutive rounds of screening invitations.
In the current study, researchers assessed the prevalence of HPV infection in these consecutive cervical samples and the changes in HPV persistence and incidence between the first, second, and third samples.
Key findings
A total of 17,252 women with at least one cervical cell sample were registered in the Trial23 between February 2017 and February 2024. In this study, researchers analyzed 16,955 cervical samples collected from 8,659 women.
The prevalence of any high-risk HPV infection in the first, second, and third rounds of cervical samples was 32%, 28%, and 31%, respectively. The prevalence of HPV types 16 and 18 (high-risk viruses covered by the 4-valent HPV vaccine) remained low over time in all analyzed samples.
The comparison between vaccinated and unvaccinated women revealed significantly lower prevalence of HPV types 16 and 18 in vaccinated women. The prevalence of this virus type was 15 to 17% before vaccination, which reduced to less than 1% in vaccinated women by 2021.
Notably, the study found that about one-third of women still have infections with high-risk HPV that are not covered by the vaccine, and that the incidence of these infections was significantly higher in vaccinated women compared to unvaccinated women. However, the prevalence differences were not statistically significant.
Regarding HPV infection persistence and incidence, the study found a high persistence for both vaccine-covered and non-covered virus types, irrespective of vaccination status. The incidence of HPV types 16 and 18 was significantly lower in vaccinated women compared to that in unvaccinated women. However, the incidence, but not prevalence, of non-covered high-risk HPV types was significantly higher in vaccinated women compared to that in unvaccinated women, a pattern the authors suggest may be due to type replacement or unmasking.
Study significance
The study reports the prevalence of HPV infection in three sets of cervical cell samples collected consecutively from young Danish women who received the 4-valent HPV vaccination in their adolescence.
According to the findings, the prevalence of infection with HPV types 16 and 18 in vaccinated women is currently less than 1%, a significant drop from the pre-vaccination prevalence. In unvaccinated women, the prevalence is 5%, which is also much lower than the pre-vaccination prevalence. The drop in prevalence in unvaccinated women indicates population immunity.
Regarding infections with high-risk HPV types that are not covered by the vaccine, the study reports a prevalence of 30% in vaccinated women and 27% in unvaccinated women, which is a non-significant difference. A persistently high prevalence of non-vaccine high-risk HPV types in both vaccinated and unvaccinated women highlights the need for continuous screening of these generations until women vaccinated as girls with the 9-valent vaccine covering all major HPV types reach the screening age. At this point, the screening model might be reconsidered, with the study suggesting that less intensive but continued screening could be appropriate.
The study finds no significant differences in the persistence of HPV 16 and 18 infections between vaccinated and unvaccinated women, which indicates that the 4-valent vaccine, which covers high-risk HPV types 16 and 18 and low-risk types 6 and 11, is a prophylactic (preventive) vaccine and not a therapeutic vaccine. The conclusion supports the finding that persistence rates were similar regardless of vaccination status.
Overall, the study findings highlight the long-term protective efficacy of the HPV vaccine and advise close monitoring of factors associated with vaccine hesitancy and low vaccine coverage, such as perceived side effects of the vaccine.Journal reference:
News
Cutting Two Amino Acids Slowed Prostate Cancer in Mice
A newly identified link between amino acid metabolism and cholesterol production may help prostate tumors adapt to hormone therapy. Prostate cancer can find ways around treatments designed to deprive tumors of the hormones they [...]
Largest-Ever Physics Survey Raises New Doubts About Our Model of the Universe
Physicists around the world remain deeply divided on key mysteries of the universe, from dark matter to quantum gravity. The standard cosmological model failed to gain majority support, and no leading theory dominated the [...]
Scientists Just Overturned a 100-Year-Old Belief About Bacteria in the Lungs
New findings raise questions about the role of microbes living in the lungs. More than 35 trillion bacteria live throughout the human body, forming microbiomes in the gut, mouth, lungs, skin, and urogenital tract. [...]
GHCE Concept
From the preface of the book Global Health Care Equivalency in the Age of Nanotechnology, Nanomedicine and Artificial Intelligence, Edited by Frank Boehm: Since the publication of my first book (Nanomedical Device and Systems [...]
Novartis, Ionis drug failure spurs questions
Pelacarsen didn’t protect heart health despite lowering levels of a protein particle, “Lp(a),” in a large clinical trial — a result with important implications for cardiovascular drug research. Dive Brief: An RNA drug from [...]
New injectable treatment helps the brain rebuild after stroke
Biomedical engineers at Duke University have created an injectable biomaterial that may help the brain recover from damage left behind by an ischemic stroke. In experiments with mice, the material transformed the cavity created [...]
Scientists Discover a Hidden “Immune Organ” Inside the Skull
Researchers discovered lymph node-like immune hubs inside skull bone marrow that appear to act as rapid-response centers for the brain. For decades, the brain was thought to operate largely apart from the immune system. [...]
Engineered tRNAs and lipid nanoparticles target nonsense mutation cystic fibrosis
Researchers have developed a potential new approach for treating a form of cystic fibrosis caused by so-called nonsense mutations, combining chemically modified transfer RNAs with lipid nanoparticles designed to deliver the therapy directly to [...]
New pancreatic cancer drug carries a $39,800 monthly list price
A groundbreaking treatment for one of the most common forms of pancreatic cancer has been approved in pill form by the FDA. Revolution Medicines’ oral tablet daraxonrasib, branded as Rasonque, reduced the risk of [...]
Researchers Have Discovered a New Way To Reduce Chronic Nerve Pain
A cancer-linked protein called BRAF may help drive chronic nerve pain, and existing cancer drugs targeting it reduced pain sensitivity in preclinical models. Chronic nerve pain can persist long after an injury and often [...]
Our books now available worldwide!
Online Sellers other than Amazon, Routledge, and IOPP Indigo Global Health Care Equivalency in the Age of Nanotechnology, Nanomedicine and Artifcial Intelligence Global Health Care Equivalency In The Age Of Nanotechnology, Nanomedicine And Artificial [...]
Quantum-Enabled Regenerative Health: Reimagining Wellness, Precision Health and Longevity Medicine
Introduction Healthcare is approaching a frontier where the quantum portfolio could influence not only how disease is diagnosed and treated, but how health itself is measured, modeled, predicted and preserved. Quantum computing, quantum simulation, [...]
FDA Clears First-of-Its-Kind Nonmedication Treatment for PTSD
The FDA has cleared a system that uses brain activity data to personalize magnetic stimulation for PTSD, adding a new nonmedication treatment option. Every day in the United States, approximately 17.5 veterans die by suicide, [...]
FDA approves breakthrough drug to treat advanced pancreatic cancer
The Food and Drug Administration (FDA) approved on Wednesday a drug that could extend the survival of those with metastatic pancreatic cancer. The drug, called daraxonrasib, will be sold under the brand name Rasonque [...]
AI Decodes a Hidden DNA Signal Linked to Disease-Causing Mutations
Machine learning identifies the likely “initiator” and enables new predictions about DNA mutations that can cause disease. Every human cell depends on tens of thousands of genes being switched on at the right time [...]
Pope Leo Urges Global Response to Congo’s Deadliest Ebola Outbreak
Pope Leo called for international action to address the Ebola outbreak in the Democratic Republic of Congo. The epidemic has claimed over 2,500 lives and is the nation's largest recorded outbreak. The Pope emphasized [...]
