(Last updated 4 March 2024)
March 4th is International HPV Awareness Day. The focus of this annual campaign is to increase awareness and education about HPV and the prevention of HPV-related cancer.
So what is HPV and who can get it?
HPV is a common virus – the human papillomavirus. There are over 100 different types of HPV. Some types are known as high-risk HPV as they have been proven to cause cervical cancer (as well as cancer of the penis, anus, vulva, vagina and throat).
You can get HPV through close skin-to-skin contact, including vaginal, anal and oral sex, and by sharing sex toys.
Most people will get HPV at some stage in their lives and most of us will never have any symptoms. Indeed, for the majority of us, our immune system will clear the virus naturally from our bodies. But for some people, the virus will remain active or lie dormant and become active again many years after infection. If the virus is not detected, it can lead to harmful health outcomes such as cervical cancer.
So this is why screening is important?
Yes. Cervical screening in Ireland is a test for HPV. A sample of cells is taken from your cervix and if HPV is found, the same sample will be looked at to see if there are any abnormal cells that could potentially develop into cervical cancer. When abnormal cells are found early, there is medical treatment available that can prevent cancer developing or manage the cancer well if it’s found at an early stage.
Prof Noirin Russell, Clinical Director of CervicalCheck, explains: “We estimate it takes 15 to 20 years for active HPV infection to cause cervical cancer, that’s why once we pick it up in screening we monitor it closely. CervicalCheck began testing for high-risk HPV in March 2020. This is because we now know that 14 strains [of HPV] cause the vast majority of cases of cervical cancer.”
So can cervical cancer be prevented if HPV infection is found early?
It will prevent some cervical cancer diagnoses, but not all.
Let’s take a look at some of the numbers with Prof Russell: “In 2022 we took approximately 248,000 screening tests and of these approximately 13.5% tested positive for HPV. Every year we treat around 12,500 women for pre-cancer abnormalities, approximately 6,400 of those women are treated for high-grade abnormalities. The majority of these are caused by high-risk HPV infections that could develop into cervical cancer if they were not identified, monitored and/or treated via screening.”
Prof Russell also tells us why HPV testing is better than the previous smear test that women used to get in screening: “If 1,000 people are screened, about 20 people will have abnormal (pre-cancerous) cervical cells. 15 of these 20 people would have these cells found through the old cytology-based [smear] test - 5 people would not and may develop cervical cancer. Whereas, 18 of these 20 people will have these cells found through primary HPV cervical screening - 2 people will not and may develop cervical cancer.”
Women are more likely to have cervical cancer found at an earlier stage when detected at screening, compared to women who are not screened. A report from the National Cancer Registry Ireland shows us that cervical cancer diagnosis at a very early stage - stage 1 - is to be expected in 80% of women diagnosed because of screening. This drops to 34% of women diagnosed with cervical cancer at stage 1 in those who are not screened.
Can HPV infection be prevented?
The HPV vaccine protects against the types of HPV that are most likely to cause cancer. The vaccine is most effective when it is given to people before they have a chance to get the virus – young girls and boys starting secondary school. Ireland has a free HPV vaccination programme in schools.
I’ve been vaccinated against HPV. Can I still develop cervical cancer?
Unfortunately, in very rare cases, yes. There are rare types of cervical cancer that cannot be detected in screening, including types that are not caused by HPV. Cancers can also develop between screening, known as interval cancers. That’s why being aware of the symptoms of cervical cancer is so important and if you do experience symptoms contact your GP.
I tested negative for HPV at my last screening. Do I still need to attend my next screening?
You should still attend for cervical screening when it’s due. While most cervical cancers are HPV-related, some are not.
In some women, HPV can lie dormant, which can give a negative HPV result. Sometimes a dormant HPV infection becomes active again many years after infection. This means that a woman who has previously tested negative for HPV can test positive on her screening test. The ability of HPV to become dormant means it's not possible to tell when a woman became infected with HPV. It’s when the virus is ‘active’, i.e. detectable, that it can cause changes in the cells of the cervix that can lead to cervical cancer.
What more can be done to prevent HPV and cervical cancer?
Cervical cancer can be prevented, yet it claims almost half a million lives globally every year. Around 90 women die of cervical cancer each year in Ireland.
Globally, the aim of cervical screening programmes is to eliminate cervical cancer. Elimination means reaching a point where there are so few cases that cervical cancer will be a rare disease and would no longer be a public health problem. Ireland is in a strong position to eliminate cervical cancer because of our HPV vaccination and cervical screening programmes, and because we have access to early diagnosis and treatment.
Dr Laura Heavey, Specialist in Public Health Medicine at the National Screening Service sums it up for us: “HPV infection is incredibly common – most people will be infected at some point in their lives. For the majority of them, their immune system will deal with the HPV infection and it won’t cause them any problems. Cervical screening will help us to identify those people with persistent infection, so that we can treat the abnormal cells caused by HPV before they develop into cancer. With cervical screening and HPV vaccination, Ireland is in a really good position to make cervical cancer a rare disease.”
Making the positive health choice
In a final word marking International HPV Awareness Day Prof Russell says: “We hope that by giving women information about HPV, letting them know that it causes more than 90% of cases of cervical cancer, and giving them details of how early vaccination, and regular HPV screening can help prevent cervical cancer, we will help women make positive health choices. Ultimately, our aim is that this leads to a continued reduction in the number of women who develop this devastating cancer.”
- Find out more about Ireland's plans to eliminate cervical cancer.
- Check the register to see when your next cervical screening is due.