Routine HPV vaccination in Scotland has led to a dramatic drop in the cervical disease which can lead to cancer, new data reveals.

The vaccine protects against human papillomavirus (HPV), which causes most strains of cervical cancer. In 2008, routine HPV immunisation of 12 and 13-year-old girls was introduced in schools across the UK. Vaccination has led to far fewer HPV infections, but there has not yet been much published evidence of the impact this has had on cervical disease and cancer.

A new study in the British Medical Journal has found a huge drop in the proportions of vaccinated women aged 20 detected at screening with cervical disease – the abnormal cells and lesions that are the precursor of cancer.

The researchers found an 89% drop in the numbers of those with the most severe levels of disease, called cervical intraepithelial neoplasia or CIN. There are three grades of CIN, with the most severe, giving the highest risk of cancer, being CIN3+.

There was an 88% reduction in CIN grade 2 or worse, and a 79% reduction in CIN grade 1.

There was a bigger decline in disease among those vaccinated at the age of 12 or 13 (89%) than in those vaccinated at 17 (51%). The vaccine is known to be more effective in those who have not yet encountered HPV, which is a sexually transmitted infection.

But there was also a drop in the levels of disease among women who have not been vaccinated, which suggests a “herd immunity” effect, say the authors – because there has been less HPV virus in the community.

Routine cervical cancer screening is still highly recommended for women, even if they have been vaccinated, but this may change, say the authors.

“Low levels of cervical cancer after routine vaccination clearly have ramifications for screening vaccinated women,” the study said.

“Although major disease is reduced in Scotland, it has not been eradicated, and continued screening is therefore necessary, particularly as for some years most women within the screening programme will not have been vaccinated.”

But in the long term, it may be that “two or three screens in a lifetime using HPV testing might be sufficient,” the paper said. “Ultimately, the clinical and economic rationale for cervical screening will need to be reviewed.”

Julia Brotherton, the medical director of Australia’s National HPV Vaccination Program Register at VCS Foundation, said in a linked editorial in the journal that the findings are “dramatic and document a considerable reduction in high grade cervical disease over time.” She called for scaling up of HPV vaccination to countries where it is not yet available or accepted.

“We must work towards a world in which all girls and their families are offered, and the majority accept, HPV vaccination, wherever they live. We must also actively develop, resource, and scale up more effective, feasible and culturally acceptable strategies for cervical screening, such as self-collection of specimens, if we are ever to effectively reduce the global burden of cervical cancer.”

Robert Music, the chief executive of Jo’s Cervical Cancer Trust, said: “The findings of this research are highly exciting and clearly demonstrate the impact of the HPV vaccine in protecting the cervical health of future generations. We are lucky to have such an effective prevention programme which means the elimination of cervical cancer is firmly on the horizon. Focusing on communities and areas where take up is below the national average should be a priority.”