Routine HPV vaccination linked to dramatic reduction of cervical disease in young women

Routine vaccination of girls aged 12 to 13 with the human papillomavirus (HPV) vaccine in Scotland has led to a dramatic reduction in cervical disease at an older age, according to a study published by The bmj aujourd & # 39; hui.

The researchers also indicated that unvaccinated women had a reduction in the disease, probably because of herd protection.

HPV is one of the most common badually transmitted infections and many countries, including the United Kingdom, offer vaccinations to girls to protect them from cervical cancer and other related cancers, later in life.

Previous studies suggest that vaccination protects against the most carcinogenic HPV 16 and 18 types, responsible for 70% of cervical cancer cases worldwide, but population data on the effect of immunization of routine on the disease are lacking.

Scotland has established a national cervical cancer screening program and, in 2008, launched a national HPV vaccination program for girls aged 12 and 13, with a catch-up program to date. 'at 18 years old.

For example, a team led by Tim Palmer of the University of Edinburgh decided to use this data to measure the impact of routine immunization of girls with the HPV bivalent vaccine (which targets HPV types 16 and 18) on abnormal cell levels and cervical lesions (known factors). cervical intraepithelial neoplasia or CIN).

CIN is divided into grades; CIN1, 2+ or 3+. The higher the number, the higher the risk of developing invasive cancer.

They badyzed the vaccination and screening records of 138,692 women born between 1988 and 1996 whose results were recorded at the age of 20 (the age of invitation to the first cancer screening cervix in Scotland until mid-2016, when the initial age was raised to 25 years).

Data include unvaccinated women (born in 1988-90, first screened selection from 2008 to 10), women eligible for catch-up vaccine at 14-17 years of age (born in 1991-94, first screening screened from 2011 to 2014). ) and women regularly vaccinated at age 12. 13 (born in 1995-96, first screening 2015-16).

After taking into account other factors that may be important, they found that, compared to unvaccinated women born in 1988, vaccinated women born in 1995 and 1996 had an 89% reduction in CIN grade 3 or worse, an 88% reduction in CIN grade 2 or higher. worse, and a 79% reduction of CIN grade 1.

A younger age at vaccination was badociated with increased vaccine efficacy (86% for grade 3 or lower CIN for vaccinated women aged 12 to 13, compared to 51% for women vaccinated at age 17).

Unvaccinated women also showed a reduction in the disease, suggesting that the interruption of HPV transmission in Scotland has created substantial herd protection.

The researchers point out some limitations. For example, the badysis was limited to women who participated in screening for cervical cancer at age 20 (51% for vaccinated women and 23% for unvaccinated women), which may have leads to an overestimation of the effectiveness of the vaccine.

However, the high use of vaccination, the similarity in the distribution of the HPV type among participants and non-participants, and the appearance of a herd protection "give the badurance that the observations can be extrapolated to the general population, "they write.

According to them, this study demonstrates that routine immunization with the bivalent vaccine against HPV is very effective against high-grade cervical disease, and they call for a re-evaluation of screening and referral services as a function of those data.

"The findings underscore the credibility of using high-risk HPV infection as an early marker of vaccine effectiveness and success, and form the foundation of the recent appeal launched by the 39 World Health Organization for a global action against cancer of the cervix uterus, "they conclude.

In a related editorial, Julia Brotherton, medical director of the VCS foundation in Australia, says the results are "dramatic and document a dramatic reduction in high-grade cervical disease over time." This study also highlights the value of integrated registries "that can systematically collect and use high quality data from screening and vaccination programs," she adds.

We must work for a world in which all girls and their families are offered, and the majority of them, the HPV vaccine, wherever they live, "she writes. also actively develop, develop resources and develop activities in a more efficient, feasible and efficient way. culturally acceptable strategies for cervical cancer screening, such as automatic specimen collection, if we ever want to effectively reduce the global burden of cervical cancer. "