Ten Most Frequently Asked Questions About the HPV Vaccine
1) Is there a safe and effective vaccine against HPV?Open or CloseYes. According to the National Cancer Institute, “The Food and Drug Administration (FDA) has approved three vaccines that prevent infection with disease-causing HPV types: Gardasil®, Gardasil® 9, and Cervarix®. All three vaccines prevent infection with HPV types 16 and 18, two high-risk HPVs that cause about 70% of cervical cancers and an even higher percentage of some of the other HPV-caused cancers. Gardasil also prevents infection with HPV types 6 and 11, which cause 90% of genital warts. Gardasil 9 prevents infection with the same four HPV types plus five additional cancer-causing types (31, 33, 45, 52, and 58).
As of May 2017, Gardasil 9 is the only HPV vaccine available for use in the United States. Cervarix and Gardasil are still used in other countries.”
Gardasil 9 is currently given on a two dose immunization schedule for those who are 14 years old or younger. Those who are 15 years old or older get 3 doses of the vaccine.
According to Merck, the vaccines manufacturer:
“GARDASIL®9 (Human Papillomavirus 9-valent Vaccine, Recombinant) helps protect girls and women ages 9 to 26 against cervical, vaginal, vulvar, and anal cancers and genital warts caused by 9 types of HPV. GARDASIL 9 helps protect boys and men ages 9 to 26 against anal cancer and genital warts caused by those same HPV types.
GARDASIL 9 may not fully protect everyone, nor will it protect against diseases caused by other HPV types or against diseases not caused by HPV.
GARDASIL 9 does not prevent all types of cervical cancer, so it’s important for women to continue routine cervical cancer screenings. GARDASIL 9 does not treat cancer or genital warts.”
Merck has created an HPV vaccine website in the US as well as one in the UK called HPVwise, with a limited set of FAQ
None of the vaccines contained live or attenuated virus. All are made against proteins that make up the structure of the virus (specifically, the L1 major capsid protein). As a result, you cannot get infected with HPV by the vaccine.
Currently available HPV vaccines do NOT contain Thiomersal (an authorized and harmless preservative used in some other vaccines), nor any other form of mercury.
The Kaiser Family Health Foundation has also produced a useful fact sheet about the HPV vaccine.
The National Foundation for Infectious Diseases has put forth a Call to Action for HPV Vaccination as a Public Health Priority
Check out the videos that are part of this archive of a 2017 conference Building Trust, Managing Risk:
Vaccine Confidence and Human Papillomavirus Vaccination. This was put on by the Vaccine Confidence Project, a London based group that works to restore confidence in and to fight misinformation about vaccines. Check out this free paper by Heidi Larson published in Nature The biggest pandemic risk? Viral misinformation Nature 562, 309 (2018) doi: 10.1038/d41586-018-07034-4
2) What studies have been done to show the vaccine is safe and effective?Open or CloseThe HPV vaccine is one of the most studied vaccines ever.
The Cochrane Library, a well respected database of reviews for all areas of the biomedicine, looked in 2018 at the safety of the HPV vaccines (all the different versions) in retrospective. Their review, Prophylactic vaccination against human papillomaviruses to prevent cervical cancer and its precursors, concluded that the HPV vaccine was indeed safe. You can read their summary conclusions here, or download the entire detailed analysis from their website (same link).
But wait, there’s more! According to the Global Advisory Committee on Vaccine Safety (GACVS), which is a part of the World Health Organization,
“Since licensure in 2006, over 270 million doses of HPV vaccines have been distributed. GACVS first reviewed the safety data in 2007 and subsequently in 2008, 2009, 2013, 2014, and 2015. Early on, the Committee was presented signals related to anaphylaxis and syncope (fainting). The risk of anaphylaxis has been characterized as approximately 1.7 cases per million doses, and syncope was established as a common anxiety or stress-related reaction to the injection. No other adverse reactions have been identified and GACVS considers HPV vaccines to be extremely safe.
Further safety data have been generated recently from Denmark, the United Kingdom and the United States of America and a comprehensive literature review has been conducted, prompting GACVS to review these new findings. Among the new data were studies looking at Guillain-Barré syndrome (GBS). The Committee has already assessed GBS as a signal and noted discrepant findings. Epidemiological studies assessing the risk of GBS following HPV vaccination have been published. including population cohort studies from Denmark and Sweden. In 2017, in response to an online publication from France suggesting an increased risk, a large self-controlled case-series study from the UK was conducted, based on a population where 10.4 million doses were administered. This most recent study found no significant increased risk for GBS after any dose of vaccine, in any of several risk periods assessed or for either vaccine brand. In addition, GBS was specifically selected as an outcome in studies from the US using the Vaccine Adverse Events Reporting System (VAERS) and the Vaccine Safety Datalink (VSD). GACVS was presented with new data from VAERS following 60 million distributed doses, and the VSD data with over 2.7 million doses administered until the end of 2015. No association between HPV vaccine and GBS was identified. Both the UK and US studies concluded, based on their respective data, that a risk of >1 case of GBS per million doses of vaccine could now be excluded.
In addition, GACVS was presented with new studies assessing other safety concerns, again from the US, as well as from Denmark. These studies included examination of specific outcomes that included complex regional pain syndrome (CRPS), postural orthostatic tachycardia syndrome (POTS), premature ovarian insufficiency, primary ovarian failure, and a further look at the risk of venous thromboembolism. With now large population level data from several countries, the Committee saw no new evidence for a causal association between HPV vaccine and those conditions. While safety data from Denmark and Sweden for >3 million women aged 18–44 years showed an apparent increased risk for celiac disease, the investigators considered that, most likely, this represented an unmasking of an existing condition during the vaccination visit rather than a causal association. Overall the study did not raise any other autoimmune safety issues of concern.
As HPV vaccine is often administered during potential childbearing years it is important to establish the safety profile in pregnant women when inadvertent administration occurs. To date no safety concerns have arisen during the pre-licensure clinical trials or in post-licensure surveillance. These reassuring data now include a recent national cohort study from Denmark that assessed 540,805 pregnancies. In addition, new data from the VSD for >92 000 eligible pregnancies were presented to the Committee. No adverse obstetric, birth or structural abnormality outcomes were observed. Inadvertent administration of HPV vaccine during pregnancy has no known adverse outcomes in either mother or infant.
CRPS and POTS continue to be presented as case reports in association with HPV vaccination, particularly from Denmark and Japan. These were initially assessed by GACVS in 2015. These conditions include a spectrum of diverse symptoms, making assessment using administrative health collections challenging. In June 2017, new data from Japan that assessed cases with diverse symptoms, including pain and motor dysfunction, were presented to the Committee. The cases were identified from a nationwide epidemiological survey involving multiple hospital medical departments of various disciplines including pain, neurology, rheumatology, paediatrics and psychiatry/psychosomatic medicine. These complex syndromes manifested in both sexes, although were more common in girls, and occurred in both vaccinated and unvaccinated individuals. The Committee concluded that since their last review, there is still no evidence to suggest a causal association between HPV vaccine and CRPS, POTS or the diverse symptoms that include pain and motor dysfunction.
Also in 2017, the WHO commissioned a systematic review of serious adverse events (SAEs) following HPV vaccines. A draft was presented to GACVS at the meeting. Using the GRADE system to systematically assess the quality of evidence, the quality of evidence in the studies was considered high across randomized controlled trials. The outcomes considered were all SAEs, medically significant conditions, new onset of chronic diseases, and deaths. Data for 73,697 individuals were reviewed. Lower level studies were excluded in favour of the large body of higher level evidence available. For all outcomes, the evidence from randomized controlled trials was supported by good quality cohort studies, with no difference in rates of selected SAEs between exposed and unexposed to HPV vaccine observed.
There are now accumulated safety studies that include several million persons and which compare the risks for a wide range of health outcomes in vaccinated and unvaccinated subjects. However, despite the extensive safety data available for this vaccine, attention has continued to focus on spurious case reports and unsubstantiated allegations. The Committee continues to express concern that the ongoing unsubstantiated allegations have a demonstrable negative impact on vaccine coverage in a growing number of countries, and that this will result in real harm. While ongoing monitoring and collection of robust data are important to maintain confidence, one of the challenges associated with the continued generation of data is that artefacts will be observed, which could pose further challenges for communication when taken in haste, out of context, and in the absence of the overall body of evidence.
GACVS discussed the importance of ensuring that immunization policy-makers and other stakeholders have ready access to articulate summaries of the vaccine safety information, to assist in evidence-based decision-making. One concrete step will be to update the HPV adverse reaction rate sheet, to reflect the most recent evidence available.
Where HPV vaccination programmes have been implemented effectively, the benefits are already very apparent. Several countries that have introduced HPV vaccines to their immunization programme have reported a 50% decrease in the incidence rate of uterine cervix precancerous lesions among younger women. In contrast, the mortality rate from cervical cancer in Japan, where HPV vaccination is not proactively recommended, increased by 3.4% from 1995 to 2005 and is expected to increase by 5.9% from 2005 to 2015. This acceleration in disease burden is particularly evident among women aged 15–44 years. Ten years after introduction, global HPV vaccine uptake remains slow, and the countries that are most at risk for cervical cancer are those least likely to have introduced the vaccine. Since licensure of HPV vaccines, GACVS has found no new adverse events of concern based on many very large, high quality studies. The new data presented at this meeting have strengthened this position.”
3) Who should get this vaccine, and at what age should the vaccine be given?Open or CloseIt’s recommended by the Centers for Disease Control (the CDC) that all girls and boys in the US get the HPV vaccine. Routine vaccination is suggested when the kids reach the age of 11 or 12 during their pre-teen check-up. However, vaccination can begin as young as age 9, and as late as age 26. Here’s a key point to remember: the vaccine must be given BEFORE a person becomes sexually active. The vaccine provides no protection against getting HPV-caused genital warts or cancers if it is given AFTER a person is infected.
A Canadian study estimated that the number of 12 year old girls needed to vaccinate to prevent a single episode of genital warts would be 8, and a case of cervical cancer 324. These estimates were based on the assumption that the vaccine procures lifelong protection and that its efficacy is 95%.
Vaccination is also recommended up to the age of 26 for those who are gay, bisexual, transgender, and those who are immunocompromised, including those who have HIV.
Merck’s has filed a Supplemental Biologics License Application (sBLA) with the FDA to get approval to sell their Gardasil 9 vaccine to women and men aged 27 to 45 for the prevention of certain HPV-related cancers and diseases. On Oct. 5, 2018, the FDA approved Gardasil 9 for this use.
4) Why doesn’t the vaccine protect against ALL strains of HPV?Open or CloseHuman papilloma viruses share some common structural proteins, but each strain also differs from one another. The vaccine is made against certain proteins that are different on each type of virus. Because of this, the vaccine only provides protection against a limited number of strains. A vaccine that targeted a protein common to all human papilloma viruses would, in theory, provide protection against all strains, but such a vaccine has yet to be created.
If you want to get into the details about differences between various strains of HPV, take a look at this paper:
Burk et al Human papillomavirus genome variants Virology. 2013 Oct; 445(0): 232–243. doi: 10.1016/j.virol.2013.07.018
5) Why do both girls and boys need to be vaccinated?Open or CloseThere are some types of HPV-caused cancers (oral and anal) that are found in both men and women. HPV also causes cervical, vulval, and vaginal cancers in women, and penile cancers in men. The HPV vaccine was originally developed to prevent cervical cancer in women, so at first it was only administered to girls. Only later, however, it was realized that the virus also caused oral and penile cancers in men, so it was approved for immunization of boys in 2011.
The most recent epidemiological data from the CDC indicates that as of 2015 there is actually a larger number of HPV-caused cancers in men than women, which supports the idea that children of both genders should be vaccinated. Vaccinating both boys and girls increases the overall level of herd immunity in a population, thereby speeding up the rate of elimination of the virus from both men and women. Wikipedia has a very detailed explanation for how herd immunity works. I also found this interesting visualization graphic that shows how herd immunity provides protection by throwing up barriers around infected people.
6) Has the introduction of the HPV vaccine actually been shown to reduce the incidence HPV infections, cervical precancers, and genital warts?Open or CloseIt certainly has in Australia, which has been a worldwide leader in HPV immunization.
The prevalence in Australia of the four HPV types included in the quadrivalent Gardasil vaccine decreased from 22.7% in 2005-07 to 7.3% in 2010-12 to 1.5% in 2015 among women 18-24 years old. That is a 93.4% decrease in HPV types since the introduction of Gardasil in Australia.
Source: Malachek et al Very Low Prevalence of Vaccine Human Papillomavirus Types Among 18- to 35-Year Old Australian Women 9 Years Following Implementation of Vaccination. The Journal of Infectious Diseases, Volume 217, Issue 10, 23 April 2018, Pages 1590–1600. https://doi.org/10.1093/infdis/jiy075
In the first four to five years after vaccination was started in Australia, precancerous abnormalities decreased by 34 per cent in 20–24 year-olds, which means these young women will be at a much lower lifetime risk of ever developing cervical cancer. A reduction in precancerous abnormalities (some of which will go away on their own) means a reduction in the various treatments used to remove these abnormalities, including the loop electrosurgical excision (LEEP) or other cone biopsy procedures, cryosurgery, laser surgery, and even hysterectomy.
Read more at https://www.cancercouncil.com.au/blog/australian-success-story-hpv-vaccine/#HhtSXA7s0SJ8Wwpx.99
In one study of 15-24 year olds, the incidence of genital warts decreased 85% in women and 71% in men following introduction of the HPV vaccine in Australia.
Source: Ali H et al Decline in in-patient treatments of genital warts among young Australians following the national HPV vaccination program. BMC Infect Dis. 2013 Mar 18;13:140. doi: 10.1186/1471-2334-13-140.
Want more proof of the effectiveness of the HPV vaccine? There was also a decrease in the incidence of genital warts in young heterosexual men in Australia, even before boys were added to the vaccination program. This illustrates just how effective the vaccination of girls has been in reducing HPV levels in both sexes.
Read more at https://www.cancercouncil.com.au/blog/australian-success-story-hpv-vaccine/#HhtSXA7s0SJ8Wwpx.99
We now have similar data in the US showing that the HPV vaccine is working:
As a result of the introduction of the HPV vaccine in 2006, we are starting to see declines in the prevalence of the HPV types that the vaccine targets. In one study, the prevalence of vaccine-type HPV decreased >90% in vaccinated women, demonstrating high effectiveness in a community setting, and >30% in unvaccinated women, providing evidence of herd protection.
See Kahn et al Substantial Decline in Vaccine-Type Human Papillomavirus (HPV) Among Vaccinated Young Women During the First 8 Years After HPV Vaccine Introduction in a Community. Clinical Infectious Disease 63, 1281 (2016) DOI: 10.1093/cid/ciw533
Also as a result of the introduction of the HPV vaccine in 2006, we are starting to see declines in the incidence of cervical pre-cancers both in those that are vaccinated as well as those who aren’t via herd immunity in both white and black women:
“In 10,206 cases, the proportion and estimated number of cases of HPV16/18-positive CIN2+ declined from 52.7% (1,235 cases) in 2008 to 44.1% (819 cases) in 2014 (P < 0.001). Declining trends in the proportion of HPV16/18-positive CIN2+ were observed among vaccinated (55.2%–33.3%, P < 0.001) and unvaccinated (51.0%–47.3%, P = 0.03) women; ages 18–20 (48.7%–18.8%, P = 0.02), 21–24 (53.8%–44.0%, P < 0.001), 25–29 (56.9%–42.4%, P < 0.001), and 30–34 (49.8%–45.8%, P = 0.04) years; CIN2 (40.8%–29.9%, P < 0.001) and CIN2/3 (61.8%– 46.2%, P < 0.001); non-Hispanic white (59.5%–47.9%, P < 0.001) and non-Hispanic black (40.7%– 26.5%, P < 0.001).”
See McClung et al Trends in Human Papillomavirus Vaccine Types 16 and 18 in Cervical Precancers, 2008– 2014 . Cancer Epidemiology, Biomarkers & Prevention DOI: 10.1158/1055-9965.EPI-18-0885
7) Has vaccination with the HPV vaccine been shown to actually cause a decrease in oral and cervical infections with HPV?Open or CloseYes. A study of more than 2,600 young adults showed that the prevalence of four different types of oral HPV, including two high risk strains (16 and 18), was 88 percent lower in those who had gotten at least one dose of the HPV vaccine compared to those who were not vaccinated.
In addition, a multi-year study in Australia has shown that their HPV vaccination program (with the older vaccine that protects against only four HPV strains) has virtually eliminated new virus infections in girls who were immunized when they were young teenagers.
Take a look at HPV Vaccination Linked to Decreased Oral HPV Infections National Cancer Institute 2017
8) Are my kids required to get the vaccine in order to attend school?Open or CloseIn the US, vaccination rates vary quite a bit from state to state. According to the Kaiser Family Foundation, “Presently at least 25 states and Washington D.C. have laws that either require HPV vaccination for school entry, provide funding to cover the costs of the vaccines, or support public education about HPV and the vaccine. D.C. and Virginia require the vaccine for girls to enter the sixth grade, but allow parents to opt out of the requirement due to medical, moral, or religious opposition. Rhode Island requires all seventh grade students to be vaccinated.”
You can see a map with state by state vaccination rates here. Rural states in general have much lower vaccination rates that other states.
Three states have gotten rid of their personal belief exemptions that made it possible for parents to opt out of required vaccines because of their beliefs. California just did it in 2015, becoming only the third state — along with Mississippi and West Virginia — to have such a strict requirement. Other states make it possible for parents to opt out of vaccinating their kids based on their personal beliefs.
The CDC has set a goal, as part of the Healthy People 2020 initiative, of getting to 80% vaccination rates for both boys and girls by 2020.
Outside of the US, vaccination rates vary widely from country to country. Countries that mandate kids get the vaccine almost always have higher vaccination rates than those that do not. In some countries only girls are vaccinated, but not boys. Australia is one of the countries that has led the way with an extensive vaccination program for girls the is difficult for parents to opt out of. See the question below I’ve heard that laws mandating vaccinations (including the HPV vaccine) are very strict in Australia. What are they doing there?
Another country with notable success in vaccinating girls is Rwanda. It’s HPV immunization campaign started in 2011 and targets girls aged between 11 and 15. The country has now immunized over 97 percent of girls from the human papilloma virus and the target is to have all women in the country free of cervical cancer by 2020. This would be a notable achievement given that cervical cancer is the most common cancer among women in Rwanda.
9) What do medical professional recommend for immunizations with the HPV vaccine?Open or CloseIn 2017, the CDC and its Advisory Committee on Immunization Practices (ACIP), together with the American Academy of Family Physicians and other medical professional organizations, recommended that the HPV vaccine be given as follows:
Patients ages 11-12 should receive two doses of Gardasil 9; however, this dosing schedule can begin as early as age 9 and as late as ages 13-14. Although it is recommended that the second dose of the two-dose schedule be administered six to 12 months after the first dose, the minimum interval between the first and second doses is five months.
This recommendation follows the FDA's approval of a request this past October to add a two-dose schedule of HPV9 for adolescents ages 9-14 as an alternative to the previously licensed three-dose schedule.
For patients initiating Gardasil 9 vaccination at or after age 15, the recommended immunization schedule is three doses. The second dose should be administered one to two months after the first dose, and the third dose should be administered six months after the first dose. Just to be crystal clear, teens and young adults who start the series at ages 15-26 continue to need three doses of HPV vaccine. Finally, if you started the vaccination series using one of the older vaccines, you can complete the series with the nine-valent HPV vaccine (Gardasil 9).
National Cancer Institute Cancer Trends Progress Report on the HPV immunization program
Sadly, physicians are not recommending the vaccine to their patients as often as they should for financial reasons. It turns out that unlike other vaccines, when doctors purchase the HPV vaccine to give to their patients, they have to use their own funds. They only getting reimbursed after they’ve administered it to patients (and billed insurance for the cost, and waited for their insurance payment to arrive). That’s expensive for primary care providers, family medicine physicians and pediatricians, who don’t make a heck of a lot of money on vaccines to begin with. A recent study estimated that a $1 increase in median provider payments for those with private insurance in a state was associated with a 0.48-percentage-point increase in the probability of initiating the HPV vaccine series and a 0.25-percentage-point increase in the probability of receiving two or more doses. The average amount doctors get paid for this varies from state to state. The lowest was in MD ($150 per shot) and the highest was Pennsylvania ($194 per shot). Bottom line: one way to increase HPV vaccination rates is to pay doctors more to administer the vaccine.
10) I can’t afford this life-saving vaccine. Who can help pay for it?Open or CloseHelp is available from several sources:
Medicaid - The Vaccines for Children (VFC) program provides vaccines for children ages 18 years and younger, or who are uninsured, Medicaid-eligible, American Indian or Alaska Native. It also covers those who have health insurance, but are underinsured (i.e. the insurance doesn’t cover any vaccines or doesn’t cover certain recommended vaccines). Underinsured children are eligible to receive vaccines only at federally qualified health centers (FQHCs) or rural health clinics (RHCs). FQHCs and RHCs provide health care to medically underserved areas and meet certain criteria under Medicare and Medicaid programs. If you need help locating an FQHC or RHC, contact your state or city’s VFC program coordinator.There are more than 40,000 healthcare providers in the US enrolled in this program. Click this link to find the VFC provider nearest where you live, or call the CDC at 1-800-CDC-INFO (1-800-232-4636) for assistance.
Children’s Health Insurance Program (CHIP) – State CHIP programs that are separate from their Medicaid programs must cover the CDC’s Advisory Community for Immunization Practices (ACIP)-recommended vaccines for beneficiaries since they are not eligible for coverage under the federal VFC. The HPV vaccine is one covered by ACIP.
The Immunization Grant Program (Section 317 of the Public Health Service Act) provides grants to states and local agencies to increase the availability of vaccines to uninsured adults in the United States. Check with your local health agency to see if the vaccine is available.
If you’re over 18, there’s a program to provide the vaccine to young adults. Merck, the manufacturer of the vaccine, has established the Merck Vaccine Patient Assistance Program (MVPAP), which is funded by Merck for adults 19 to 26 years of age who cannot afford vaccines. It’s a private and confidential program provides vaccines free of charge to eligible adults, primarily the uninsured who, without our assistance, could not afford needed vaccines. To qualify you must be 19 to 26 years of age, don’t have health insurance, and can’t afford to pay for the vaccine. Details can be found at Merck Helps by clicking this link.
Less Frequently Asked Questions About the HPV Vaccine
11) For how long a time period is the vaccine protective?Open or CloseThe exact time period is not known for sure. The most currently used vaccine, Gardasil 9, was only introduced in 2014, so the earliest participants in clinical trials have just been treated for 6-7 years. A report in the journal Lancet showed that vaccine efficacy has been maintained for six years (Lancet. 2017 Nov 11;390(10108):2143-2159. doi: 10.1016/S0140-6736(17)31821-4). A literature review/meta-analysis The Efficacy and Duration of Vaccine Protection Against Human Papillomavirus (Dtsch Arztebl Int. 2014 Sep; 111(35-36): 584–591) showed no loss of long term protection from HPV vaccines.
12) When was the vaccine first introduced?Open or CloseIn the US, the Food and Drug Administration (FDA) has approved three vaccines that prevent infection with disease-causing HPV types: Gardasil®, Gardasil® 9, and Cervarix®. Gardasil was originally introduced in 2006 (for girls only), Cervarix was first marketed in the US in 2009 (again, only for girls), and Gardasil 9 replaced Gardasil in the US in 2014. Up until 2010, the vaccines were only given to girls, after which they started to be given to both boys and girls when it was clearly understood that HPV also causes oral, anal, and penile cancers in men. Cervarix was withdrawn from the US marketplace in 2016 due to low market demand, leaving Gardasil® 9 as the only HPV vaccine for sale in the US.
The two Gardasil vaccines are manufactured by Merck, whereas Cervarix is a product of GlaxoSmithKline. Click this link for information on which countries have licensed Gardasil 9, and this link for which countries had licensed Cervarix.
13) Does infection with one strain of HPV prevent a person with being infected by other strains?Open or CloseNo. You can be infected with multiple strains of HPV at the same time. Being infected with one strain does not provide protection against infection with a different strain. A study was done looking at women who were referred for HPV testing when they were having cells from their cervixes examined. Twenty four percent of the women were positive for HPV infection, and 19 percent of those infected with one strain also harbored a second strain. The overall percentage of women who were infected with at least two strains of HPV was 4.6 percent. "Women who harbor multiple infections are at higher risk for cervical lesions than those ever infected with one type only and should be followed more closely," said Eduardo L. Franco, Dr.PH., professor of epidemiology and oncology, and director, division of cancer epidemiology at McGill University.
The research raises the possibility that in women with multiple infections, their immune systems may be less robust in clearing the infections. HPV 16, the most well known cancer causing strain, was found in 9 percent and 14 of single and multiple HPV infections, respectively.
14) Does this vaccine cause autism?Open or CloseNo. There is absolutely no evidence that the HPV vaccine (or for that matter, any vaccine) causes autism. None at all.
Most of the misinformation about vaccines causing autism have been focused on the MMR vaccine. It doesn’t. Read this article that reviews in great detail why there is no association. It includes references for 140 papers that all support this, including the most recent huge analysis (Measles, Mumps, Rubella Vaccination and Autism: A Nationwide Cohort Study) of more than 650,000 children in Denmark. This Danish study found zero evidence of any association between the MMR vaccine and autism.
15) If you’ve already been infected with one strain of HPV, can the vaccine prevent you from being infected by another strain?Open or CloseIn theory the vaccine should prevent someone who is already infected with HPV from being infected by a second strain, providing that the second strain is one of the nine strains that the Gardail 9 vaccine works against. Those who received the earlier vaccines (Cervarix or Gardasil) that only protected against two strains of HPV (16 and 18) or four strains of HPV (16, 18, 6, and 11), respectively, could also get some benefit from the most recent vaccine, Gardasil 9, that provides protection against a total of nine strains.
Having said that, it’s the two most prevalent cancer-causing strains (16 and 18) are found in the vast majority of HPV-caused cancers. For example, WHO reports that 70 percent of cervical cancers are linked to these two strains. One study estimated that the Gardasil 9 vaccine may prevent an additional 4.2 percent to 18.3 percent of cancers compared to the vaccines targeted at just strains 16 and 18. Thus, there are diminishing returns in getting the newest vaccine if you have already been immunized with the earlier ones. As always, discuss this with your doctor to weigh the pluses and minuses. You may also want to check if your insurance company would pay for new HPV vaccinations if you’ve previously been vaccinated with one of the earlier vaccines.
16) How many different strains or types of HPV cause cancer?Open or CloseThere are 16 strains that are thought to cause cancer (16, 18, 31, 33, 34, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68 and 70). These strains are often referred to as “high risk” strains. The term 'high-risk' means that these types of HPV are more likely than other types to cause cancer. However, most HPV-associated cancers are linked to just two types of HPV: types 16 and 18. There are over 170 different types of HPV that have been identified to date. Forty HPV strains are sexually transmitted.
17) How many different strains of HPV are there?Open or Close
18) Why don’t more parents get their kids vaccinated against HPV if it’s so dangerous?Open or CloseThis is a very complex subject that’s been looked at in a number of studies. There are many reasons, and they cut across all parts of the ideological spectrum. Many parents are simply uninformed about the long-term dangers of HPV infections, and don’t understand the need to vaccinate boys as well as girls. They’ve picked up on the general climate of fear and misinformation about vaccines that pervades some communities. This leads them to take the path of least resistance and skip the vaccines. Let’s take a look at many of the oft-stated (but erroneous) reasons parents refrain from getting their kids vaccinated, but now with a cancer context.
Belief That Childhood Illnesses Are Not All That Dangerous
For many of these diseases, parents wrongly believe that they’re innocuous, a mere inconvenience in their lives. No big deal. They’ve bought into the erroneous idea that vaccines may do more harm than the disease ever could. They’ve never seen children hospitalized and/or dying from measles, diphtheria, or whooping cough (pertussis) infections. Every one of these diseases can be fatal, but few parents personally know anyone who died from them. They think it won’t happen to their kids, or their friend’s kids. Out of sight, out of mind.
HPV-induced cancers are a significantly more serious medical issue than the usual spectrum of childhood illnesses. Let me share what I’ve learned about one of the two most prevalent HPV cancers (and the one I was diagnosed with): oropharyngeal (oral) cancer. Unless it’s detected very early, patients are not even eligible for surgery. It’s straight to radiation and chemo, with their accompanying side effects. Nausea. Vomiting. Tiredness. Radiation burns. Difficulty swallowing. Loss of taste. Damaged salivary glands. And that’s if it hasn’t spread yet. The vaccine would prevent most of the cancer-causing infections with HPV, and could cut the number of oropharyngeal cancer cases in men by 70 percent. Cancer prevention is always preferable to cancer treatment.
When you daydream about your kids growing up, you likely picture graduations, weddings, and grandchildren, not their funerals. Maybe what parents need to see is an illustrative display of guts and gore, something reminiscent of the movies used to scare the crap out of teenagers in high school drivers ed classes. Imagine a series of cancer horror films in the same vein as Mechanized Death, Wheels of Tragedy, or Highway of Agony. These days, that would take the form of YouTube videos showing how HPV infections can lead to bulging tumors, feeding tubes, disfigured patients, and bereaved family members. Would this help turn the tide and up the vaccination rate?
Objection To Mandated Vaccination Requirements
Some parents resent being told by their state or local governments, or school districts, that they need to get their kids vaccinated against a variety of childhood diseases. For them, it’s an issue of freedom, being able to choose what’s right for their kids. That’s NOT the case with the HPV vaccine. Only three jurisdictions (RI and VA, along with the District of Columbia) currently mandate HPV vaccinations to attend school. Yes, many states have introduced legislation around HPV infections, but that simply funds vaccinations and/or educates families about the vaccine. Parents are simply being given the chance to make a good decision for their children. We need more of them to take advantage of this opportunity. These vaccines are truly lifesaving!
They Don’t Know About HPV Or The Cancers It Causes
Vaccinations against HPV differ from the ones given for most childhood diseases in three important ways: (1) the common childhood diseases are easily transmitted between kids via the air or casual contact. HPV cannot be passed that way. (2) HPV immunization is recommended for both boys and girls when they’re about 11 or 12, which is much later than for other childhood vaccines. (3) Unlike other childhood illnesses, where acute disease rapidly follows exposure, the cancer-causing effects of HPV only manifest themselves many years, or even decades, after infection.
Concerns That The Vaccine Will Lead Kids To Promiscuity
Because HPV is a sexually transmitted disease, some parents fear (as with birth control) that vaccination will quell their kids fears about sex. This will lead their children down the path to promiscuity. There’s simply no data that supports that conclusion. And while it’s clear that the virus is sexually transmitted, it’s unclear as to how that process takes place. Research on this subject is continuing.
Lack of Trust in Companies That Make Drugs in General, and Vaccines in Particular
People will say they simply don’t trust pharma companies to make vaccines that are both safe and effective. They argue that these companies are just in it for the money. Neither of these things are true. Pharma companies do have a bad reputation with the public due to a number of highly-publicized scandals over the past couple of decades. I wrote an opinion piece about this, Pharma’s tarnished reputation helps fuel the anti-vaccine movement, for those of who are interested in the subject.
Many parents think they can’t get their kids immunized against HPV because they simply don’t have the money to pay for it. They haven’t heard about the Vaccines for Children program of the CDC. It provides vaccines at no cost for children whose families have an inability to pay. The government buys the vaccines at a discount and sends them to providers who have signed up with the program. It’s not limited to the HPV vaccine and covers immunizations that will protect children from as many as 16 diseases. See the answer to the next question for more details about other ways to get the vaccine at no or reduced cost.
There are effective strategies for geting parents to vaccinate their kids against HPV. Here’s a link to a one hour video on Strategies for Recommending HPV Vaccination for Pre-teen Youth (2018) by Kristin Oliver, MD, MHS Icahn School of Medicine at Mt. Sinai.
The American Academy of Pediatrics also had suggestions for educating parents. Check out their HPV Champion Toolkit
You can also see recommendations from the American Cancer Society on this subject.
You can also check out this Powerpoint presentation on HPV infection and immunization rates in adolescents by Jennifer E. Dietrich, MD, Msc, Baylor College of Medicine. It looks at such issues as age of first intercourse (7% BEFORE the age of 13!), infection statistics of women, and vaccine coverage by different racial/ethnic groups.
19) If a woman’s been given the HPV vaccine, does that mean that she no longer requires screening for cervical cancer?Open or CloseNo. The CDC recommends that she should still be screened. Both older versions of the HPV vaccine as well as the current one don’t protect individuals against all HPV types that cause cervical cancer. Vaccination would certainly reduce the odds of her developing cervical cancer, because the vaccine is directed against the most prevalent cancer causing strains, but it cannot guarantee it. Also, keep in mind that while 70 percent of cervical cancer cases are caused by HPV 16 or 18, the remaining 30 percent of cases are not caused by these viral strains. Finally, women who got the vaccine after they became sexually active may not get the full benefit of the vaccine if they had already been exposed to HPV. That’s why screening would still be a good idea.
20) Does the U.S. have a national goal for the percentage of people who should be immunized against HPV?Open or CloseYes there is, but let’s start by saying where we are now. As of 2017, nearly half of all adolescents age 13-17 were up to date (i.e. had gotten the full number) of shots of the HPV vaccine.
Source: CDC. (2018). National, Regional, State, Selected Local Area Vaccination Coverage Among Adolescents Aged 13-17 Years—United States, 2017. MMRW 67(33)
What percentage of vaccinated youth is the goal?
According to the CDC, “After the quadrivalent HPV vaccine was licensed in 2006, Healthy People 2020 stated an objective of 80% coverage with 3 doses of HPV vaccine for females by age 13 to 15 years. It also stated objectives to “Reduce the death rate from cancer of the uterine cervix below a target of 2.2 deaths/100,000 females (from a baseline of 2.4 per 100,000 in 2007)” and “Reduce invasive uterine cancer to 7.2 new cases per 100,000 females.55 There is also a stated goal to “increase the proportion of women who receive a cervical cancer screening based on the most recent guidelines” with a target of 90% of women 21 to 65 years of age receiving screening (from a baseline of 84.5% in 2008). There are currently no stated goals for reduction of anogenital warts, RRP, or non-cervical HPV-associated cancers.”
What is Healthy People 2020? It’s a program launched by the US Department of Health and Human Services in 2010 that has four overarching goals:
“- Attain high-quality, longer lives free of preventable disease, disability, injury, and premature death;
- Achieve health equity, eliminate disparities, and improve the health of all groups;
- Create social and physical environments that promote good health for all; and
- Promote quality of life, healthy development, and healthy behaviors across all life stages.”
Because it is not looking likely that this goal will be met, the American Cancer Society has set a new goal of 80% coverage with the HPV vaccine for 2026. Note that the Healthy People 2020 goal was specifically set for girls only, whereas the new goal from the ACS is for both girls AND boys.
21) Are there side effects associated with getting the HPV vaccine?Open or CloseAs with nearly all vaccines, there are mild side effects associated with getting the HPV vaccine. These usually last a few hours to a day.
According to the World Health Organization, In the arm where the vaccine is given:
“• Pain is felt by about 8 in 10 people.
• Redness or swelling is experienced by about 1 in 4 people.
Headache: About 1 in 3 people will develop a headache.
• Mild fever (100° F/38° C) is experienced by about 1 in 10
• Moderate fever (102° F/39° C) is experienced by about 1 in
About one in a million people who receive a vaccine of any kind will experience a strong allergic reaction (such as anaphylactic shock). For this reason, health care providers should ask about allergies before giving a vaccine and advise whether a known allergy is relevant to the specific vaccine being given. The person being vaccinated should stay in the clinic for 15 minutes afterwards for observation.”
22) Does getting the HPV vaccine hurt?Open or CloseUnfortunately, it often does. This is because this particular vaccine is one of a type of vaccines that is referred to as reactogenic. According to Wikipedia “Reactogenicity events are adverse events that are common and known to occur”, such as a sore arm at the injection site, or a fever. Typically, reactogenicity with vaccines is often observed when the vaccine contains an adjuvant (a chemical additive intended to enhance the recipient's immune response to the vaccine antigen), but it can also occur with non-adjuvanted vaccines. All versions of the HPV vaccine have had added adjuvants, including the one currently available in the U.S., Gardasil 9.
23) How many countries vaccinate their kids against HPV?Open or CloseAccording to the World Health Organization, “Over 100 countries have licensed one or more HPV vaccines, and as of 9 August 2017, globally 74 countries (including 33 countries in the WHO European Region) have added HPV vaccination to their national immunization programme for girls, and 11 countries also for boys.”
Note that the number of countries now vaccinating boys has increased in 2018 (see question 24 below).
The World Health Organization has recommended that ALL countries include the HPV vaccine in their routine vaccination schedules.
24) Are there many countries that only vaccinate girls, not boys?Open or CloseYes. In fact, these countries are the rule, not the exception. According to the World Health Organization, of the 74 countries that have national HPV immunization programs, only 13 of those countries (as of 2017) vaccinate boys as well as girls (that’s only 15% of these countries). As of late 2018, about 20 countries have now decided to vaccinate boys as well as girls (see below).
I do not believe there are any countries that only vaccinate boys, not girls.
Let’s look at some other countries making news recently:
New countries adding the vaccine for girls:
Not all countries even have a policy of vaccinating girls, but this is slowly changing. On Oct. 10, 2018, Hong Kong officials announced that all school girls age 9-11 will be vaccinated against HPV. Vaccinations will be given at school. The goal is to decrease the number of cervical cancer cases. In 2015, there were 500 new cervical cancer cases in Hong Kong, and 169 women died of the disease. Taiwan also announced that they will start vaccinating girls at the end of 2018. Kenya announced it will provide the vaccine for free to girls starting in 2019 following a successful pilot program. Malawi will start vaccinating girls in 2019.
Another recent success story is the Philippines. While the government has a program for vaccinating girls, it does not reach those living in the poorer corners of the islands. Doctors Without Borders launched a massive vaccination program in the Tondo slums to vaccinate 25,000 girls between the ages of 9 and 13. Merck provided the vaccine at a discounted rate. You can read about this successful effort here.
Countries that have recently started to vaccinate boys:
Australia has been a leader in HPV vaccination. It mandated the HPV vaccine for girls beginning in 2007. In 2013, the mandate was expanded to boys. In 2017 New Zealand added boys in their HPV vaccination program as well.
The UK has just agreed to finally start vaccinating boys as part of the Department of Health and Social Care, although a start date for the vaccinations has not been announced. This will include England, Wales, and Scotland, but no announcement has been made about Northern Ireland. Denmark announced in late 2018 that boys would get the HPV vaccine. Portugal announced that boys would get the HPV vaccine starting in 2019. Germany will start vaccinating boys in 2018 or 2019. Ireland will start vaccinating boys in 2019. Antigua will start vaccinating boys in 2019. I am trying to confirm that Belgium’s French-speaking Wallonia region and the Dutch speaking part of the country will start paying for HPV vaccines for boys as well! Guyana announced in 2019 that boys will get the HPV vaccine.
With so many countries in Europe coming on board to vaccinate boys, some at WHO have raised concerns that this will lead to a shortage of the vaccine for immunizing girls in poorer countries of the world.
25) I’m worried that the HPV vaccine will make my kids promiscuous.Open or CloseThere’s no need for parents to worry about this. First, a number of studies have shown that kids getting the vaccine don’t wind up having sex any more often than kids who don’t. Also, keep in mind that the vaccine, while protecting against HPV, does nothing to prevent other sexually transmitted infections, including gonorrhea, syphilis, chlamydia, herpes, and HIV. There are no vaccines to prevent these other sexually transmitted infections. Therefore, the HPV vaccine should really have little effect on whether or not kids have sex. Parents should remember that cancer prevention via the HPV vaccine beats having their kids someday need cancer treatment.
You can also look at this paper published in the journal Pediatrics, Legislation to Increase Uptake of HPV Vaccination and Adolescent Sexual Behaviors. The authors concluded, “Implementation of HPV legislation was not associated with changes in adolescent sexual behaviors in the United States.”
26) Who invented the HPV vaccine?Open or CloseThe vaccine was first developed at the University of Queensland in Australia by researchers Ian Frazer and Jian Zhou. Their work built upon the initial discovery that HPV was associated with and causes cervical cancer, which is credited to German researcher Harald zur Hausen. He shared the Nobel Prize in Medicine in 2008 for this groundbreaking work, along with the discoverers of the HIV virus.
27) Is the HPV vaccine made from live viruses?Open or CloseNo, there is NO live virus in the HPV vaccine, and therefore it is NOT possible to “catch” HPV from the vaccination. HPV vaccines are made by using yeast to generate one of the HPV proteins, called L1, from HPV. The L1 protein is then purified and self-assembles into pentamers (an organized arrangement of five of the protein molecules), and next 72 of the pentamers self-assemble into a structure known as a virus like particle (VLP). Think of the VLP as being like the shell of an egg, but without any yolk or whites contained inside. The VLP are hollow particles that are good at generating an immune response. Scientists at Merck (who manufacture the vaccine) combine VLPs made from L1 proteins from nine different strains of HPV to produce the Gardasil 9 vaccine.
See Conway and Meyers, Replication and Assembly of Human Papillomaviruses. J Dent Res. 2009 Apr; 88(4): 307–317. doi: [10.1177/0022034509333446]
28) Is it safe to give the HPV vaccine to women who are pregnant?Open or CloseApparently so, although this has never been tested due to ethical considerations. According to the Global Advisory Committee on Vaccine Safety (GACVS), which is a part of the World Health Organization, “inadvertent administration of HPV vaccine during pregnancy has no known adverse outcomes in either mother or infant.”
29) What’s the difference between a preventative HPV vaccine, and a therapeutic one?Open or CloseMost of the time when we speak about HPV vaccines, we are talking about those that are preventative and are used in immunizations to prevent infection with the virus, such as Gardasil 9 (see above). All of the existing vaccines to date have been preventative.
However, efforts are underway to develop therapeutic vaccines, which are designed to be given to patients diagnosed with HPV-caused cancers. These vaccines are often designed to target the E6 and E7 proteins, which are thought to be the key ones the virus uses to turn normal cells into cancer cells. You can read a report about efforts to develop one of these therapeutic vaccines here. As of 2018, there have been no therapeutic HPV vaccines approved in the US by the FDA.
An international, drug-company sponsored study has been launched to investigate the use of a therapeutic vaccine in treating CIN2 (this is high grade cervical intraepithelial neoplasia) in women who are contemplating future pregnancies. The vaccine will be given as an alternative to surgery, which can weaken the cervix and lead to problems in future pregnancies.
30) If the HPV vaccine is truly effective against certain high-risk strains of HPV, won’t those eventually be replaced in the population by other strains not covered by the vaccine?Open or CloseThere is no definitive answer to this question. The subject is complicated, and much of the work done to date revolves around mathematical modeling. But how does this operate in the real world, and specifically, with HPV? There has been evidence of strain replacement with other vaccines, but it is highly likely that this mechanism will vary a lot between different types of vaccines. Factors involved include how many replacement strains are available in the population, how many strains the vaccine is effective against, what percentage of the population is vaccinated, the virulence of the various strains, and how communicable is the particular pathogen (in this case, a virus).
Take a look at Evidence for cross-protection but not type-replacement over the 11 years after human papillomavirus vaccine introduction. Covert et al. Hum Vaccin Immunother. 2019.
Look at theoretical modeling of this phenomenon in Martcheva et al Vaccine-induced pathogen strain replacement: what are the mechanisms?J R Soc Interface. 2008 Jan 6; 5(18): 3–13. doi: 10.1098/rsif.2007.0236
For a look at HPV, see the study by Markowitz et al Prevalence of HPV After Introduction of the Vaccination Program in the United States Pediatrics. 2016 Mar;137(3):e20151968. doi: 10.1542/peds.2015-1968.
Finally, this issue has also been addressed in Murall et al Could the human papillomavirus vaccines drive virulence evolution? Proc Biol Sci. 2015 Jan 7; 282(1798): 20141069. doi: 10.1098/rspb.2014.1069
31) What’s been the focus of TV ads for the HPV vaccine?Open or CloseThe early ads for the first HPV vaccine (Cervarix) were focused exclusively on vaccinating girls, and the intent was clearly on prevention of cervical cancer.
That’s changed now with current ad campaigns making the case that girls AND boys need to be vaccinated. The only HPV vaccine still being used in the US is Gardasil 9 that’s produced by Merck. They’ve run several types of ad campaigns as of late. The focus of the first campaign was on showing parents feeling guilty that they didn’t vaccinate their kids, who went on to develop HPV-caused cancers. Here’s an example.
The second ad campaign by Merck is called Versed, and focuses on reaching out to young millennials with an educational question and answer approach. Some liked the approach, but I question how effective it will be on a population that has had all of their vaccination decisions made by their parents when they were growing up.
32) What is the Vaccine Adverse Event Reporting System (VAERS), and how good is it in tracking harm caused by vaccines?Open or CloseThe Vaccine Adverse Event Reporting System (VAERS) is a reporting process that has been put in place for patients or doctors to record information about problems observed after people have been vaccinated. Its purpose is widely misunderstood. It does NOT exist to track specific and prove adverse reactions caused by vaccines; it is simply there to record information. The purpose of the system is clearly denoted on the VAERS website as follows:
“When evaluating data from VAERS, IT IS IMPORTANT TO NOTE THAT FOR ANY REPORTED EVENT, NO CAUSE-AND-EFFECT RELATIONSHIP HAS BEEN ESTABLISHED. Reports of all possible associations between vaccines and adverse events (possible side effects) are filed in VAERS. Therefore, VAERS COLLECTS DATA ON ANY ADVERSE EVENT FOLLOWING VACCINATION, BE IT COINCIDENTAL OR TRULY CAUSED BY A VACCINE. THE REPORT OF AN ADVERSE EVENT TO VAERS IS NOT DOCUMENTATION THAT A VACCINE CAUSED THE EVENT.”
So the reporting of any event after receiving a vaccination is simply a record. It does NOT prove the vaccine caused that issue. Let me put this in a different context to see if that helps. Imagine if there was a similar system that was in place for people to report problems for some period of time after they have shopped at Target or taken a taxi. That database might note that you began to feel sick four days after your shopping trip, or the taxi ride. But does that mean that your sickness was CAUSED by the shopping excursion or the taxi ride? No. It could be related, but maybe not. Coincidences happen all the time. Keep this in mind as you look at data from VAERS.
33) What, exactly, is herd immunity, and how does that concept work with viruses and vaccinations?Open or CloseHerd immunity is a concept where non-immunized individuals are protected against infection by some agent because they are surrounded by a large number of people who have been immunized. These immunized people serve to break a chain of contagion, and as a result the infectious agent does not reach the non-immunized person. The exact percentage of the population that needs to be immunized for the population to be protected varies depending on the ease and mechanism of transmission of the infectious agent. For example, a greater percentage of people need to be immunized to prevent the spread of viruses that are transmitted by coughing or sneezing compared to those like HIV and HPV that are sexually transmitted.
Herd immunity becomes very important in protecting those who can’t be immunized for some reason, such as those with weakened immune systems, including newborns, people with HIV, cancer patients who have received chemotherapy and radiation, etc. For sexually transmitted infections (STIs) including HPV, high levels of immunity in one sex induces herd immunity for both sexes in many instances. Vaccinating women against HPV, however, would provide no protection to men who are exclusively homosexual.
Modeling in this paper suggests that at 80% vaccination coverage of both girls AND boys would lead to the elimination of four strains of HPV, including the two most prevalent cancer causing strains, 16 and 18. M Brisson et al Population-level impact, herd immunity, and elimination after human papillomavirus vaccination: a systematic review and meta-analysis of predictions from transmission-dynamic models. Lancet Public Health. 2016 Nov;1(1):e8-e17. doi: 10.1016/S2468-2667(16)30001-9. Epub 2016 Sep 27.
Wikipedia has a very detailed explanation for how herd immunity works.
I also found this interesting visualization graphic that shows how herd immunity provides protection by throwing up barriers around infected people.
Here’s another terrific visualization graphic of herd immunity. It’s set up for measles, but the same principle applies to HPV infections.
34) I’ve heard that laws mandating vaccinations (including the HPV vaccine) are very strict in Australia. What are they doing there?Open or CloseVery strict indeed, and these apply to all required vaccines, not just the HPV vaccine. In 2016 the Australian federal government introduced a law called “no jab, no pay,” under which parents of unvaccinated children lose government benefits and welfare rebates — costing them up to 15,000 Australian dollars. That policy also didn’t allow for non-medical exemptions. You can get more details by reading this NY Times piece No Jab No Pay: How Australia is Handling Vaccinations.
There is legislation pending that would ban unvaccinated children in preschool and child care centers, and would fine these centers up to 30,000 Australian dollars, or about $24,000, if they allow an unvaccinated child to attend. Parents who object to vaccination on philosophical or religious grounds would not receive exemptions. The new laws are meant to combat the efforts of anti-vaccination groups.
As a result of their aggressive vaccination program for girls, Australia may become the first country to eradicate HPV-caused cervical cancers (according to the International Papillomavirus Society). You can read more about this in In Australia, Cervical Cancer Could Soon Be Eliminated, or look at this free paper in The Lancet The projected timeframe until cervical cancer elimination in Australia: a modelling study DOI:https://doi.org/10.1016/S2468-2667(18)30183-X
Compare this with the United States, where only three states have gotten rid of their personal belief exemptions that made it possible for parents to opt out of required vaccines because of their beliefs. California just did it in 2015, becoming only the third state — along with Mississippi and West Virginia — to have such a strict requirement. It’s much easier for parents in the other 47 states to opt out of having their children vaccinated for “personal reasons”, putting their kids and others at risk.
35) Are there global disparities in the use of the HPV vaccine?Open or CloseHere’s an article from 2016 that looks at HPV vaccination rates globally. It explains why women in poor countries (where the vaccine is not generally available) remain at greater risk of developing cancer (especially cervical cancer) and dying from HPV than women from wealthier countries. See Global estimates of human papillomavirus vaccination coverage by region and income level: a pooled analysis: Bruni et al Lancet Vol. 4, No. 7, e453-3463 (2016)
36) How many people would need to be vaccinated against HPV in order to prevent a single case of cancer?Open or CloseThe answer to this isn’t known. A 2007 paper by Brisson et al estimated that using the vaccine available at the time (Gardasil, which only protects against four strains of HPV: 16, 18, 6, and 11), you would have to vaccinate about 324 girls to prevent one case of cervical cancer. This estimate may be good, or it may be bad. It’s based on mathematical modeling. Whatever the number is, it would actually be much better today for two reasons. One, the most recent vaccine, Gardasil 9, protects against five additional cancer causing strains of the virus (31, 33, 45, 52, and 58) compared to Gardasil original. That makes the current vaccine more effective at preventing cancer, although not hugely so since most cases (about 70%) of cervical cancer are thought to be caused by strains 16 and 18. The other thing to keep in mind is that the HPV vaccine not only prevents most cases of cervical cancer in women, it should also prevent most cases of vaginal, vulval, oropharyngeal, and anal cancer as well.
According to the National Cancer Institute, the HPV virus is believed to be responsible for about 70% of cervical cancers, 65 percent of vaginal cancers, 50 percent of vulvar cancers, 95 percent of anal cancers, and 70 percent of oropharyngeal (back of the throat, tonsil, and base of the tongue) cancers.
Data from the CDC indicates that in 2015, oropharyngeal cancers made up only 14% of all HPV-cancers in women. The most prevalent HPV-cancer in women is cervical cancer (48%), followed by anal cancers (18%), vulval cancers (16%), and vaginal cancers (3%).
So overall, the number of girls needed to treat with the most recent vaccine in order to prevent a single case of cancer might be more in the range of about half of the previous estimate, or around 162 girls. But nobody knows for sure.
I have been unable to find any estimates for the number of boys needed to be vaccinated to prevent a single case of oropharyngeal, anal, or penile cancer in men.
Brisson M et al Estimating the number needed to vaccinate to prevent diseases and death related to human papillomavirus infection CMAJ. 2007 Aug 28; 177(5): 464–468. doi: 10.1503/cmaj.061709
37) What is the HPV-FASTER concept?Open or CloseThe basic goal of this idea is to speed up the elimination of cervical cancer across the world The concept, proposed in 2016 by Xavier Bosch and colleagues, is a generalised HPV vaccination campaign aimed at females aged from 9 up to 30–45 years, paired with at least one HPV-screening test at any age above 30 years, and triage/diagnostic assessments of women who screen HPV positive. You can read more about this in HPV-FASTER: broadening the scope for prevention of HPV-related cancer. This article is an abridged version of Nat Rev Clin Oncol 13:119–132. doi:10.1038/nrclinonc.2015.146
38) How does HPV vaccine coverage vary from state to state?Open or CloseIn the US, vaccination rates vary quite a bit between the states. They also, of course, vary a lot over smaller areas within each state, and at least some of that is driven by pockets of anti-vaccine parents. For example, in the Seattle area where I live, there’s a community on Vashon Island that has vaccination opt-out rates that are five times the state average.
So what are the laws covering vaccination? According to the Kaiser Family Foundation, “Presently at least 25 states and Washington D.C. have laws that either require HPV vaccination for school entry, provide funding to cover the costs of the vaccines, or support public education about HPV and the vaccine. D.C. and Virginia require the vaccine for girls to enter the sixth grade, but allow parents to opt out of the requirement due to medical, moral, or religious opposition. Rhode Island requires all seventh-grade students to be vaccinated.”
You can see a map with state by state vaccination rates here. Rural states in general have much lower vaccination rates that other states.
The CDC has set a goal, as part of the Healthy People 2020 initiative, of getting to 80% vaccination rates for both boys and girls by 2020.
You can also look at this paper published in the journal Pediatrics, Legislation to Increase Uptake of HPV Vaccination and Adolescent Sexual Behaviors. The authors concluded, “Implementation of HPV legislation was not associated with changes in adolescent sexual behaviors in the United States.”
39) What exactly are adjuvants, and why are they added to vaccines?Open or CloseThe CDC has a very clear explanation of what adjuvants are:
“An adjuvant is an ingredient used in some vaccines that helps create a stronger immune response in people receiving the vaccine. In other words, adjuvants help vaccines work better. Some vaccines that are made from weakened or killed germs contain naturally occurring adjuvants and help the body produce a strong protective immune response. However, most vaccines developed today include just small components of germs, such as their proteins, rather than the entire virus or bacteria. Adjuvants help the body to produce an immune response strong enough to protect the person from the disease he or she is being vaccinated against. Adjuvanted vaccines can cause more local reactions (such as redness, swelling, and pain at the injection site) and more systemic reactions (such as fever, chills and body aches) than non-adjuvanted vaccines.”
The current vaccine against HPV, Gardasil 9, is not a weakened virus vaccine. It contains but a single protein made by the virus (see the answer to question 27 above). That’s why an adjuvant is used to generate a stronger immune response. In the case of Gardasil 9, this adjuvant is an aluminum based compound. Aluminum based adjuvants are the most commonly used ones in vaccines. The CDC notes that “aluminum salts, such as aluminum hydroxide, aluminum phosphate, and aluminum potassium sulfate have been used safely in vaccines for more than 70 years. Aluminum salts were initially used in the 1930s, 1940s, and 1950s with diphtheria and tetanus vaccines after it was found they strengthened the body’s immune response to these vaccines.”
To learn even more about the levels of aluminum in vaccines vs. the levels found in breast milk and formula, and why aluminum amounts in vaccines are too small to be harmful, check out this detailed Q&A from the Vaccine Information Center at the Children’s Hospital of Philadelphia.
40) The HPV vaccine has to be given BEFORE infection to prevent cancer and genital warts, but the vaccine to prevent shingles (Shingrix) is given to older adults decades AFTER they were infected with the virus that causes chickenpox. Why is there a difference? Why won’t the HPV vaccine work after infection, like the shingles vaccine?Open or CloseThe short answer is that the two viruses are of different types and function in distinct ways to cause disease. Human papilloma virus infections are generally fought off by your immune system, but in some cases the virus itself integrates itself into your cellular DNA. On rare occasions this leads to the development of cancer, sometimes many decades later. Put another way, it’s not an active viral infection that causes disease; its the activity of only a few viral genes within your cells that can eventually lead to problems. The vaccine is meant to attack the virus BEFORE it can integrate itself into your DNA. The vaccine cannot prevent the cells from developing cancer once the viral DNA has been integrated, nor does it target the infected cancer cells.
With the chickenpox virus (varicella-zoster) that causes shingles, the entire virus itself can lurk for decades within your nerve cells. As you get older, a decline in the efficiency of your immune system allows the virus to re-emerge, where it can lead to the painful rashes and nerve damage associated with shingles. The shingles vaccine works by generating an immune response against the entire virus, thereby preventing it from causing (or lessening the severity of) disease.
The incidence of infection with HPV and chickenpox viruses are similar in that the infection rate is very high in adults in the U.S. More than 90 percent of sexually active adults will get an HPV infection during their lifetimes, and nearly 100 percent of adults will have been exposed to the chickenpox virus (even if they don’t realize it). Gardasil 9 (the current HPV vaccine) is targeted at preventing cancer and genital warts in older adults (except for cervical cancer, which strikes younger women), and the shingles vaccine (Shingrix) is also targeted at the older adult population. In that way they share another similarity. However, the HPV vaccines are meant to be given to kids, whereas Shingrix is only given to older adults in their 50s, 60s, and older.
The viruses are transmitted in different ways. Chickenpox is transmitted from person to person by directly touching the blisters, saliva or mucus of an infected person. It can also be transmitted through the air by coughing and sneezing. In contrast, HPV is passed via sexual contact; it is NOT transmitted via coughing and sneezing. See question 4 on the HPV FAQ page for more details.
Finally, researchers are trying to develop therapeutic vaccines against HPV that would work after you’ve been infected, just as the shingles vaccine works following infection. Whether such efforts will be successful is unknown. See the answer to question 29 above for more details.
41) I heard a story saying that data suggesting the HPV vaccine causes cervical cancer was faked. What’s the story?Open or CloseThis is a sad story and it’s true. This was apparently done as part of a deliberate effort to stop people from vaccinating their kids against HPV. The data was contained in an article in the Indian Journal of Medical Ethics entitled “Increased incidence of cervical cancer in Sweden: Possible link with HPV vaccination”. The paper was published under a pseudonym by someone claiming to be a member of the Karolinska Institute in Sweden. However, no one with that name ever worked there, and the paper was subsequently withdrawn from the journal. You can read more about the incident here. This also illustrates why one should be suspicious of articles published in obscure journals.
42) Is poor oral health associated with survival in head and neck cancer patients?Open or CloseYes it is, but the subject is complicated. That’s because poor oral health can be associated with poverty (leading to fewer dental visits), which is turn may delay the detection of oral cancers, leading to worse patient outcomes. In addition, poor oral health may contribute to changes to the oral microbiome via the presence of dental/oral inflammation or immune responses, or due to failure to brush teeth properly or consistently. The issues here are complex and can be difficult to separate out.
Farquhar et al Poor Oral Health Affects Survival in Head and Neck Cancer Oral Oncol. 2017 October ; 73: 111–117. doi:10.1016/j.oraloncology.2017.08.009.
A binary choice: cancer prevention with the vaccine, or someday possible treatment without it