Blog Posts

HPV vaccine shown to reduce cervical cancer

It’s official: the human papillomavirus (HPV) vaccine prevents cervical cancer.

The world has known for several years that the HPV vaccine is effective in preventing the occurrence of certain HPV infections, as well as preventing the changes in cells that can precede cervical cancer. But up until recently, the world’s first groups of HPV vaccinated girls had not been old enough to see any impact of the vaccine on the numbers of women developing cervical cancer. As the first vaccinated cohorts are now reaching their late 20s – when the risk of cervical cancer would usually increase – and they are old enough to enter cervical screening programmes, the impact is starting to be recognised at the real-world level. With data now coming in, two recent studies have shown for the first time that the HPV vaccine does, indeed, protect against cervical cancer.

In October 2020, a study from the Karolinska Institutet in Sweden used medical registry data to compare the incidence of cervical cancer in women who had the HPV vaccine when they were girls, against women who didn’t have the vaccine when they were girls. The study found that women who had been vaccinated against HPV have a 47 in 100,000 chance of developing cervical cancer in contrast to women who have not been vaccinated against HPV, who have a 97 in 100,000 chance of developing the disease. They concluded that HPV vaccination almost halves individuals’ chances of developing cervical cancer.

Whilst this Swedish study looked at data on an individual level, an English study published today in the Lancet has taken a population level approach to this public health issue for the first time. Researchers from King’s College London and Public Health England, funded by Cancer Research UK, found that HPV vaccination has dramatically reduced incidence of cervical cancer across the female population in England who were offered the vaccine at ages 12-13.

For this group, there was an 87% reduction in the number of women being diagnosed with cervical cancer and a 97% reduction in a severe cervical abnormality that can precede cancer. These numbers are particularly impressive as the vaccine that this group received was only targeted towards HPV strains responsible for 70% of cervical cancer cases (HPV16 and 18). In addition to this, the study included girls who were offered the vaccine but didn’t receive it. This means that the study may have captured the beginnings of herd immunity in protection against HPV16 and 18, and cross-protection against other strains of HPV. In total, between 2008-2019, it is estimated that England’s HPV vaccination programme prevented 450 cervical cancer cases, as well as 17,200 pre-cancerous cervical abnormalities.

The ability to draw conclusions of this scale across a national population of women is incredibly exciting. Michelle Mitchell, Cancer Research UK’s chief executive, said: “It’s a historic moment to see the first study showing that the HPV vaccine has and will continue to protect thousands of women from developing cervical cancer.”

These results will have implications for populations all over the world. The rationale for investing in HPV vaccination is now even more convincing, with this robust evidence supporting prioritisation of cervical cancer prevention. It has been well-documented that the HPV vaccine is safe. Now, any decision-makers who expressed caution regarding the effectiveness of the vaccine will hopefully take confidence from these results as well. As CCAE Network, we believe that these findings are so positive, they are difficult to ignore. Because the data shows signs of herd immunity and cross protection, the results of vaccination programmes could be considered even better than initially expected. We hope that this evidence can be used to spur policymakers into ambitious commitments to invest in HPV vaccination introduction, or encourage decision-makers and leaders to prioritise improving uptake in those countries which already offer HPV vaccination to eligible populations. We would also like to see similar research being conducted in high burden countries in a few years’ time when vaccinated cohorts are old enough to begin cervical screening.

So, what can advocates do to emphasise the importance of these findings to stakeholders? We are in the process of creating a mini communications toolkit that incorporates this evidence. These tools could be used to approach stakeholders in your state or country to commit to achieving 90% HPV vaccination coverage by 2030. We will notify you when this toolkit is ready, so please keep an eye on our social media channels for updates.

The journey towards cervical cancer elimination has been fortified by these findings. We now need to help governments, public health providers and wider communities take their next steps along that path.

Information on the study from the Karolinska Institutet can be found here and the New England Medical Journal article on the study can be found here.