A group of experts have investigated the effects of Human Papillomavirus Vaccination (HPV) on cervical cancer screening in Alberta, Canada. The results suggest that quadrivalent HPV vaccination significantly reduces high-grade cervical abnormalities, subsequently reducing the risk of cervical cancer. The findings of the study, published recently in Canadian Medical Association Journal (CMAJ), fortify the importance of population-based HPV vaccinations.
During the study, a school-based quadrivalent HPV vaccination program was implemented across the province of Alberta in 2008. The impact was examined in the following years by observing results of cervical cancer screening tests known as Pap tests.
Qualifying as one of the most common sexually transmitted infections, HPV remains a largely ignored virus. About 79 million Americans are currently infected with HPV, with about 14 million new cases added each year. HPV goes unnoticed in many cases, eventually leading to serious health issues such as genital warts and cervical cancer. Additionally, cancers of the vulva, penis, vagina, anus, neck and throat can also be contracted.
The study cohort had 10,204 participants born between 1994 and 1997, who had at least one Pap test between 2012 and 2015. Amongst the participants, women who had negative Pap tests (cytology results) which included 8723 participants represented the control group. On the other hand, women with low-grade and high-grade cervical abnormalities, comprising of 1,481 women, represented the experiment group. Apart from atypical squamous cell intraepithelial lesions (abnormal cell growth) of various degrees qualifying as cervical abnormalities, it was found that 56% of participants were unvaccinated, while 44% of participants received at least one HPV vaccination before each screening test.
The significant findings of the study compared the cytology results with the unvaccinated, partially vaccinated (2-doses) and fully vaccinated (3 or more doses) participants. Amongst the fully vaccinated women, only 11.8% showed abnormal cytology results, while 16.1% of unvaccinated women had abnormal results. On the other hand, women who received partial vaccination did not show any significant improvement in comparison with unvaccinated participants.
The eight-year long study and interpretation has finally reached a substantial finding — complete vaccination for HPV helps prevent early signs of cervical abnormalities, subsequently reducing the risk of developing cervical cancer later in life.
It is very common for a sexually active person to contract HPV at least once in a lifetime. The virus can be contracted during vaginal, anal or oral sex with a virus-infected partner and can be contracted even if you have only one sex partner. Using Latex condoms is often suggested to prevent viral transmission.
Most times, the virus dissipates without causing any harm, however HPV does have an ability to cause symptoms years after the exposure. Deceptive by nature, HPV is not often remembered as a culprit for genital warts or cervical cancer diagnosis occurring in later stages of life. The virus has a number of strains which are stratified as high-risk and low-risk strains. Amongst the high-risk viral strains, HPV 16 and HPV 18 result in 70% of cervical cancer cases. Approximately 17,600 women and 9,300 men in the US fall prey to cancers caused by HPV exposure.
Although HPV depicts an unsettling picture, there are commercially available vaccinations which minimize the virus’s harmful effects. To prevent grave consequences after contracting HPV, young girls are recommended to be vaccinated at the age of 12, before they become sexually active and are first exposed to the virus.
It is to be noted that vaccinations are not only recommended for girls or women but are also important for boys and men because not only do they protect against cervical cancer but they also provide protection against other cancer types mentioned above.
The Centers for Disease Control and Prevention (CDC) recommends vaccinating boys and girls of 11-12 years of age. The vaccinations are given in three shots over a period of six months, if one fails to receive all three shots, the protection against the virus is not fully assured. For individuals who have matured without receiving vaccination, catch-up vaccinations are recommended for men through age 21 and women through age 26.
Amongst the approved vaccinations, Gardasil is recommended for both girls and boys, while Cervarix is recommended for females between the ages of 9-25. However, you may be wondering why Cervarix is recommended for females only. There is a simple reason — Cervarix work against cervical cancer-causing strains which affect only girls. Gardasil, on the other hand, works against 4 strains of HPV which are likely to harm males and females alike.
Although the study failed to comment on the pathology of the cytology tests, it used a population-based surveillance database which assured accuracy of results. This study can be a stepping stone in initiating population-based studies across countries which can compare vaccination dosage and early disease prevention on a larger scale, consequently helping reduce cervical cancer-related mortality in women.