HPV Is Not Just a Women’s Health Issue
HPV’s link with cervical cancer has led to the infection being discussed largely in the context of women’s health. A new study demonstrates why this should not be the case.
Complete the form below to unlock access to ALL audio articles.
Human papillomavirus (HPV) is a group of related viruses that infect the skin and mucosal membranes. HPV infection is the most common sexually transmitted disease (STD) worldwide; nearly all sexually active men and women will be infected at some point during their lifetime according to the Centers for Disease Control and Prevention.
While HPV is often discussed in the context of women’s health and cervical cancer risk, a recent study published in The Lancet Global Health found that over one-third of men aged 15 years and over are infected with at least one type of HPV. One in five men is infected with one or more types of HPV that are considered “high-risk” strains. “This statistic might be surprising to some, however, HPV affects both men and women, with a substantial impact on public health,” explains Christine Meyer, MD, practicing physician and founder of CMMD and Associates medical practice.
Here, we explore how HPV viruses cause infection and – in some cases – cancer, and what the findings of the new study mean for HPV prevention efforts.
How does HPV infect human cells?
There are over 200 types of HPV that can be transmitted sexually, and individuals can be infected by more than one strain at the same time. “These viruses are categorized into low-risk and high-risk types based on their association with health problems,” says Meyer. Low-risk forms of HPV do not typically cause disease, but high-risk forms of HPV can lead to the development of various types of cancer.
HPV is primarily transmitted through direct skin-to-skin contact. “The virus enters the body via breaks in the layer of cells (epithelial cells) which make up our skin and also the internal linings of our mouth, anus and vagina to name a few,” explains Dr. Gareth Nye, senior lecturer at the University of Chester, program lead for the BMedSci Medical Science Program and expert in maternal and fetal health. “Once the virus has bypassed this layer, it infects the cells leading to the virus being protected from our immune system. From here they can replicate and spread to neighboring cells, damaging the body’s cells as it does so.”
The history of HPV and cervical cancer research
Nowadays, the link between HPV and cervical cancer is well established. Its discovery dates back to the 1970s, when German virologist Harald zur Hausen went against the grain by proposing that HPV could be a causal agent behind this type of cancer. In pursuit of answers, he spent several years studying a variety of HPV strains and analyzing patient biopsies for HPV viral DNA. Ultimately zur Hausen discovered that patients with HPV16 and HPV18 were more likely to develop cervical cancer, a groundbreaking feat that earned him a share of the 2008 Nobel Prize in Physiology or Medicine.
Over 95% of cervical cancer cases are due to HVP infection according to the World Health Organization, and HPV16 and HPV18 are found in ~70% of cancer biopsies worldwide. zur Hausen’s work paved the way for the first HPV cervical cancer vaccine, developed at the University of Queensland in Australia throughout the 1990s and approved for human use by the United States Food and Drug Administration in 2006.
The HPV vaccine is an example of a preventative vaccine, meaning they are designed to prevent, not treat, HPV infection. Current HPV vaccines use a combination of virus-like particles to trigger an immune response and the production of neutralizing antibodies against HPV.
HPV is a global health issue affecting women and men
Extensive research has explored the epidemiology of HPV in women, perhaps owing to its association with cervical cancer. But over recent decades, HPV’s association with other types of cancer has been determined, including oropharyngeal cancer, anal cancer, penile cancer, vaginal cancer and vulvar cancer. An estimated 69,400 male cancer cases were attributed to HPV infections in 2018 alone, according to The International Agency for Research on Cancer.
“While there are many studies conducted looking at HPV in women, very few address HPV in males and even fewer are conducted globally,” says Meyer. This is problematic as, without a complete understanding of HPV prevalence across men and women, data on the overall global disease burden and transmission risk is skewed. It also becomes increasingly challenging to create, implement and evaluate HPV and cancer prevention programs.
The majority of existing studies on HPV prevalence in men – the last of which was published in 2011 – have been conducted in high-income countries, or in populations that are at an increased risk of HPV infection, such as men that have sex with men, men with HIV or HPV-symptomatic men, according to the authors of the new The Lancet Global Health study. The lead author of the work, Laia Bruni Coccoz, MD, is head of the Unit of Infections and Cancer Information and Interventions (UNIC-I) in the Cancer Epidemiology Research Program and coordinator of the Institute of Oncology/International Agency for Research on Cancer HPV Information Center. Alongside colleagues in the field, Coccoz aimed to provide updated and global data on HPV infection in men.
The researchers conducted a systematic review and meta-analysis, analyzing studies on the prevalence of genital HPV infection in males that had been published between 1995–2022. Approximately 31% of men are infected with one strain of HPV, and 21% are infected with high-risk strains, the data suggests. Prevalence of HPV was higher in young adults, particularly those between 25–29 years old. “This statistic emphasizes the need for comprehensive HPV prevention strategies that include both genders. It highlights that HPV is not just a women's health issue but a broader public health concern, given its association with various cancers in men and women,” says Meyer.
“It remains true that males remain key in the biology of this disease, and we should be considering them in all HPV prevention attempts including education and awareness. If more males understand the role they play, many more cases could be prevented,” adds Nye. “This study is a strong piece of research. The methods here involve combining the finding from other peer-reviewed sources and undertaking new analysis to gain a larger overview of the patterns of disease.”
How can HPV be detected and prevented?
Most often HPV infection does not cause noticeable symptoms, particularly in its early stages, which means those affected might not be aware of it. In some individuals, HPV might cause visible warts to form on the genitalia, the anus, mouth or throat, but this is not always the case.
“The most reliable way to detect an HPV infection is through medical tests, such as pap smears for cervical HPV infections in women and specific HPV DNA tests,” Meyer explains. “Regular screening and healthcare check-ups are essential for identifying and managing HPV infections and associated health risks.” Currently, a simple screening test for HPV is lacking for men, which in Meyer’s opinion is further reasoning why The Lancet Global Health study is “so important.”
As HPV infection is often symptomless, prevention is key, explains Nye: “Safe sex practices in particular are so important. Using condoms is a very good way of reducing the risk of infection. Avoiding the sharing of sex toys without through cleaning is also advised,” he says. “Anyone who is engaging in regular sexual activity either with multiple partners or a new partner should be getting regular sexual health screens to ensure infections of any kind are recognized as soon as possible. It’s also crucial if you do have an infection to tell recent partners, so they too can get tested and treated.”
Beyond practicing safe sex, HPV vaccines are now available for both males and females. “These vaccines are most effective when administered before sexual activity begins, because they protect against the most common high-risk HPV types that can lead to cancer. HPV vaccination is recommended for adolescents and young adults,” says Meyer.
Nye emphasizes that, though Coccoz and colleagues’ study is a stride forward for understanding HPV prevalence in men, further research is still warranted: “Although this is strong evidence, it is not current and newly undertaken research and so you can only take so much from the findings. This will become a solid basis for future studies targeting HPV spread around the world but for now, the findings should be taken very seriously,” he concludes.
Drs. Christine Meyer and Gareth Nye were speaking with Molly Campbell, Senior Science Writer for Technology Networks.