Last updated on September 9th, 2020 at 10:52 am
Despite all that’s going on with the coronavirus pandemic, great studies about important subjects as HPV vaccine effectiveness continue to be published. And this study, which followed Nordic women for 14 years, continues to show us that the HPV vaccine is safe and effective.
So let’s take a moment to review this new article about HPV vaccine effectiveness, so that you have more evidence to support the value of the vaccine.
All about HPV and HPV vaccines
I know I add this section to every article I write about HPV vaccines. It is updated almost every time with additional information about HPV or the vaccine. Moreover, there are readers who want to know more about HPV, and this section can help someone get up-to-speed quickly.
Genital and oral human papillomavirus (HPV) infections are the most common sexually transmitted infections (STI) in the USA. HPV is generally transmitted from personal contact during vaginal, anal or oral sex.
It’s important to note that there are more than 150 strains or subtypes of HPV that can infect humans – however, only 40 of these strains are linked to one or more different cancers. Of those 40 strain, most are fairly rare.
Although the early symptoms of HPV infections aren’t serious and many HPV infections resolve themselves without long-term harm, HPV infections are causally linked to many types of cancers in men and women. According to current medical research, here are some of the cancers that are linked to HPV:
In addition, there is some evidence that HPV infections are causally linked to skin and prostate cancers. The link to skin cancer is still preliminary, but there is much stronger evidence that HPV is linked to many prostate cancers.
HPV is believed to cause nearly 5% of all new cancers across the world, making it almost as dangerous as tobacco in that respect. According to the CDC, roughly 79 million Americans are infected with HPV – approximately 14 million Americans contract a new HPV every year. Most individuals don’t even know they have the infection until the onset of cancer. The CDC also states that over 43,000 HPV-related cancers are diagnosed in the USA every year. It may be several times that amount worldwide.
There were two HPV vaccines on the world market before 2014. GSK, also known as GlaxoSmithKline, produced Cervarix, a bivalent (protects against two HPV strains) vaccine. It has been withdrawn from the US market (although available in many other markets), because of the competition from the quadrivalent (immunizes against four different HPV strains) and 9-valent (against nine HPV strains) Gardasil vaccines.
Merck manufactures Gardasil, probably the most popular HPV vaccine in the world. The first version of the vaccine, quadrivalent Gardasil, targets the two HPV genotypes known to cause about 70% of cervical cancer and two other HPV genotypes that cause genital warts. In Europe and other markets, Gardasil is known as Silgard.
The newer Gardasil 9, approved by the FDA in 2014, is a 9-valent vaccine, protecting against HPV Types 6, 11, 16, 18, 31, 33, 45, 52, and 58. It targets the four HPV strains found in the quadrivalent version, along with five additional ones that are linked to cervical and other HPV-related cancers. Both versions of Gardasil are prophylactic, meant to be given to females or males before they become exposed to possible HPV infection through intimate contact.
Gardasil is one of the easiest and best ways to prevent a few dangerous and, to abuse the definition slightly, common cancers that afflict men and women. Without a doubt, the HPV vaccine prevents cancer.
Currently, in the United States, the Advisory Committee on Immunization Practices (ACIP) recommends that preteen girls and boys aged 11 or 12 are vaccinated against HPV. The immunization is also recommended for teenage girls and young women up to the age of 26 who did not receive it when they were younger, and teenage boys and young men up to the age of 21.
Let me sum this all up so that if you come away from this section with nothing else, you get this summary. HPV is a sexually transmitted disease. HPV causes 43,000 cancers a year in the USA alone. The HPV vaccine prevents becoming infected by HPV, which means you are protected from these cancers.
HPV vaccine effectiveness study
The study, by Susanne K Kjaer et al, was published in June 2020 by The Lancet’s EClinical Medicine. Young women, 16-23 years of age, from Denmark, Iceland, Norway, and Sweden who had received three quadrivalent HPV vaccine does during a randomized, double-blind, placebo-controlled stdy were followed for effectiveness for an addition 10 or more years.
The researchers took tissues samples during organized cervical cancer screening programs and were adjudicated for histopathology diagnoses and also tested for HPV DNA. Serum was also collected at year 9 and year 14 of the study to assess antibody responses.
The results were:
- No cases of HPV16/18-related high-grade cervical dysplasia were observed in the vaccinated population (n=2121).
- HPV vaccine effectiveness was calculated to be 100% for at least 12 years, possibly through 14 years.
- Seropositivity rates was estimated to be >90% against HPV6/11/16/18 (the four HPV types covered by the quadrivalent HPV vaccine) using a very sensitive IgG immunoassay.
The authors concluded that:
Vaccination of young women with qHPV vaccine offers durable protection against HPV16/18-related high-grade cervical dysplasia for ≥12 years, with a trend toward continued protection through 14 years post-vaccination, and induces sustained HPV6/11/16/18 antibody responses for up to 14 years post-vaccination. There was no evidence of waning immunity, suggesting no need for a booster dose during that period.
There really isn’t much to say. In this large study of HPV vaccine effectiveness, the researchers concluded that there was no evidence of waning immunity against HPV. This is a very safe and extremely effective vaccine. Frankly, I’m not sure I’ve seen effectiveness this high for any other vaccine.
If you want to protect you or your chldren against HPV-related cancers, this vaccine is for you.
- Kjaer SK, Nygård M, Sundström K, Dillner J, Tryggvadottir L, Munk C, Berger S, Enerly E, Hortlund M, Ágústsson ÁI, Bjelkenkrantz K, Fridrich K, Guðmundsdóttir I, Sørbye SW, Bautista O, Group T, Luxembourg A, Marshall JB, Radley D, Yang YS, Badshah C, Saah A. Final analysis of a 14-year long-term follow-up study of the effectiveness and immunogenicity of the quadrivalent human papillomavirus vaccine in women from four nordic countries. EClinicalMedicine. 2020 Jun 20;23:100401. doi: 10.1016/j.eclinm.2020.100401. PMID: 32637895; PMCID: PMC7329692.