The American Cancer Society (ACS) updated its guidelines for human papilloma virus (HPV) vaccination on July 8, 2020 and now recommends that doctors and other healthcare providers routinely administer the two-dose HPV vaccination series to boys and girls between the ages of nine and 10.1 Currently, the federal Advisory Committee on Immunization Practices (ACIP) recommends the HPV vaccine be given at age 11 or 12, but states that the vaccine “can be given” starting at age nine.
The ACS further adapted the ACIP guidelines for adults, recommending that providers inform individuals aged 22 to 26 who have not been previously vaccinated or who have not completed the series, that vaccination at older ages is less effective in lowering cancer risk. Further, the ACS does not endorse the ACIP recommendation for “shared decision making” regarding HPV catch-up vaccination for individuals aged 27 to 45.
ACS Says Vaccinating Younger Children Increases Vaccination Rate
In making their recommendations, the ACS maintains that HPV vaccination has been shown to be more effective at younger ages and that immunity does not wane over time. ACS argues that vaccination at an earlier age would still confer protection throughout adolescence and early adulthood, offering more opportunities for children to complete the two-dose HPV vaccination series for children under age 15.2 Some providers want to vaccinate younger children because they have found it easier to vaccinate when there is less discussion about sexual behavior as a risk factor.3
According to ACS, vaccination of adults aged 27 through 45 has minimal public health benefit and is unlikely to prevent a significant number of cancers, precancers, or genital warts.4
HPV is a Common Virus
Human papilloma virus is the most common sexually transmitted infection (STI), with acquisition generally occurring soon after first sexual activity.5 About 79 million Americans are currently infected and, in most cases, HPV infections are transient, asymptomatic, and go away on their own without causing health problems. When HPV infection does not go away and if left undiagnosed and untreated over a period of years or decades, then genital warts and cervical or other kinds of cancer can develop.6 7
About 60 of the 100 HPV types cause warts on areas like the hands or feet. The other 40 or so types are associated with sexual contact. Not all of the 40 sexually transmitted human papillomaviruses cause serious health problems. High risk HPV strains include HPV 16 and 18, which are associated with about 70 percent of cervical cancers. Low risk HPV strains, such as HPV 6 and 11, are associated with about 90 percent of genital warts, which rarely develop into cancer.8
Pap Smears Effectively Detect and Prevent Cervical Cancer
Routine cervical cancer (Pap smear) screening is part of a woman’s routine health care and has been shown to greatly reduce both the number of cervical cancer cases and deaths from the disease. The Pap test, which is generally done every three years beginning at age 21, takes cells from a woman’s cervix and those cells are examined under a microscope for abnormalities.
Although HPV infection of the cervix is very common, most infections will be cleared by the immune system over the course of one to two years. Because most HPV infections are transient and produce only temporary changes in cervical cells, overly frequent screening could detect HPV infection or cell changes that may be unlikely to cause cancer.9
HPV testing, which looks for the presence of high-risk HPV types in cervical cells, may also be done alone or with the Pap smear, and is recommended for women every five years after age 30.10 A study released on July 8, 2020 concluded that co-testing with Pap and HPV together was more effective at detecting cancer than with either test done alone.11
Other Cancers Related to HPV
The ACS estimates that in 2020 13,800 new cases of invasive cervical cancer will be diagnosed in the U.S. and will result in approximately 4,290 deaths.12 In addition to cervical cancer, there are five other cancers associated with chronic HPV infection: mouth and throat (oropharyngeal), vaginal, penile, anal and vulvar.
In 2018, the ACS estimated that in the U.S. (population of over 325 million):
- About 51,540 cases of oral cavity or oropharyngeal cancer will be diagnosed and result in 10,030 deaths
- About 5,170 cases of vaginal cancer will be diagnosed and result in 1,330 deaths.
- About 2,320 cases of penile cancer will be diagnosed and result in 380 deaths.
- About 8,580 cases (5,620 in women and 2,960 in men) of anal cancer will be diagnosed and result in 1,160 deaths (680 in women and 480 in men)
- About 6,190 cases vulva cancers will be diagnosed and result in 1,200 deaths.13
HPV Vaccine Approved Despite Safety Concerns
Despite the availability of effective screening and treatment options for the detection and prevention of cervical cancer, Merck’s Gardasil vaccine was granted Fast Track status and an accelerated approval by the FDA in 2006. Gardasil contained strains 16, 18, 6 and 11 was initially approved for use in females between ages nine and 26 years old. In 2011, the CDC recommended that males also be routinely vaccinated with the HPV vaccine and, in 2014, five additional strains (31, 33, 45, 52 and 58) were added to Gardasil.14 Merck’s Gardasil-9 is currently the only HPV vaccine available for use in the United States.
Concerns about the strength of the scientific evidence used by the FDA to license the first HPV vaccine as safe and effective were raised by the National Vaccine Information Center (NVIC) in a 2006 press release.15 NVIC pointed out that Merck inappropriately used a bioactive placebo (aluminum) as a control in pre-licensure trials and that principal investigators ignored red flag safety signals reported during those trials, including cases of death and development of inflammatory autoimmune disorders in participants. NVIC also pointed out that the sample sizes of the adolescent population targeted for vaccination were too small in the trials and that surrogate markers for efficacy used in the trials did not prove the vaccine actually prevented cancer.
The CDC reported that, in 2017, nearly 49 percent of adolescents aged 13 to 17 had completed the HPV series, and nearly 66 percent had received the first dose.16
Cervical Cancer Rate Decreased 0.7 percent Since 2006
The CDC reports that among teen girls, infections with HPV types that cause most HPV cancers and genital warts have dropped 86 percent, and among young adult women, infections have dropped 71 percent.17 Rates of new cervical cancer in 2006 when the HPV vaccine was introduced were 8.2 per 100,000 women with an incidence of 12,704. In 2017, the CDC reports an incidence of 7.5 per 100,000 women, or 12,831 cases.18
Because HPV vaccines do not protect against all HPV types that cause cervical cancer, the CDC recommends that vaccinated women should continue with routine cervical cancer screening.19
1 Saslow D, Andrews KS et al. Human papillomavirus vaccination 2020 guideline update: American Cancer Society guideline adaptation ACS Journals July 8, 2020.
2 U.S. Centers for Disease Control and Prevention. HPV Vaccine Recommendations. Mar. 17, 2020.
3 See Footnote 1.
5 CDC. Human Papillomavirus Vaccination for Adults: Updated Recommendations of the Advisory Committee on Immunization Practices. MMWR Aug. 16, 2019; 68(32): 698–702.
6 CDC. U Genital HPV Infection – Fact Sheet. Aug. 20, 2019.
7 See Footnote 5.
8 WebMD. HPV.
9 U.S. National Institutes of Health National Cancer Institute. HPV and Pap Testing. Dec. 20, 2019.
11 Kaufman HW, Alagia DP et al. Contributions of Liquid-Based (Papanicolaou) Cytology and Human Papillomavirus Testing in Cotesting for Detection of Cervical Cancer and Precancer in the United States American Journal of Clinical Pathology July 8, 2020.
12 American Cancer Society. Key Statistics for Cervical Cancer.
13 National Vaccine Information Center Can HPV Cause Injury and Death?
14 National Vaccine Information Center What is the History of HPV Vaccine Use in America?
15 National Vaccine Information Center. Merck’s Gardasil Vaccine Not Proven Safe for Little Girls. June 27, 2006.
16 CDC. More US adolescents up to date on HPV vaccination. Aug. 23, 2018.
17 CDC. Human Papillomavirus (HPV). Aug. 15, 2019.
18 National Cancer Institute. U.S. Cancer Statistics: Data Visualizations. June 2020.
19 See Footnote 9.