The first HPV vaccine was approved in 2006, and a number of studies have already shown that the vaccine reduces the risk of serious early-stage cervical cancer.
Cervical cancer takes a long time to develop, and therefore we have had to wait to see the effect of the HPV vaccine on the actual incidence of the cancer disease. The results are now available:
Danish researchers are among the first in the world to demonstrate that the risk of cervical cancer is considerably less for women with an HPV vaccination before they reached 20.
“It’s fantastic” said Susanne Krüger Kjær, a consultant at the Department of Gynaecology at Rigshospitalet and a professor at the University of Copenhagen, as well as a head of research at the Danish Cancer Society Research Center.
“The effect of the HPV vaccine has been clearly documented in clinical studies, where everything is very well-controlled. But in this new study, we can see that women in the general population who have received the vaccine have a significantly lower risk for cervical cancer compared with women who have not been vaccinated. This is an amazing result, and we believe that the combination of the HPV vaccination and the screening programme for cervical cancer could actually lead to us more or less eliminating cervical cancer in Denmark,” said Susanne Krüger Kjær.
Large study for almost 900,000 women
The new study includes almost 900,000 women in Denmark who were 17-30 years old in 2006-2019. Of these, almost 40% received the HPV vaccination before they reached 17.
The results show that, compared with unvaccinated women, women vaccinated before 17 had 86% less risk for cervical cancer. Women who were vaccinated as 17-19 year-olds had a 68% less risk for cervical cancer.
“The picture is less clear for the women who were in their 20s when they were vaccinated. However, this does not mean that the vaccine doesn’t work for older women,” said Susanne Krüger Kjær.
“The oldest women in the study weren’t vaccinated as part of the child vaccination programme, and many of them could have chosen to receive vaccine because they were at higher risk of developing cervical cancer, for example because early-stage cervical cancer had already been ascertained. The results emphasise that girls should preferably be vaccinated at an early age, and that one of the best things you can do for your daughter is to accept the offer of an HPV vaccination in the child vaccination programme,” said Susanne Krüger Kjær.
New vaccine protects even better
In Denmark, girls are offered an HPV vaccination when they reach the age of 12 years, and HPV vaccination has been part of the child-vaccination programme since 2009. Over the years, different vaccines have been used in the programme, and the women taking part in the new study have been vaccinated with a vaccine that protects against fewer types of HPV than the so-called nonavalent vaccine that was introduced in the vaccination programme in 2017.
“The ‘old’ vaccines primarily protected against HPV16 and HPV18, which are also behind around 70% of all cases of cervical cancer. The nonavalent vaccine protects against nine types of HPV, so we hope that we prevent almost 90% of all cases of cervical cancer by vaccination,” said Susanne Krüger Kjær.
The new study has been published in the prestigious Journal of the National Cancer Institute.
Facts about HPV and cervical cancer
Approx. 370 women in Denmark are diagnosed with cervical cancer each year.
Cervical cancer comes from chronic infection with HPV virus.
HPV is transferred sexually and is very contagious. Most are infected with HPV one or several times in the course of their lives.
HPV infections usually disappear by themselves, but in rare cases, the infection becomes chronic and may result in cell changes in the cervix. In some cases, the cell changes develop into cervical cancer.
HPV vaccination in Denmark
The Danish child vaccination programme offers free HPV vaccination for both girls and boys from the age of 12 years.
Girls have been offered an HPV vaccination since 2009. Boys were included on the programme in 2019.
HPV causes a number of types of cancer besides cervical cancer, namely cancer of the vagina and women's outer genital organs. In men, HPV can cause cancer of the penis and HPV may also cause anal cancer and cancer of the mouth in both sexes.
For further information or an interview with Professor Susanne Krüger Kjær, please contact:
Linda Svenstrup Munk, PR advisor
Tel.: +45 22 96 68 98