By Norma Erickson
Are HPV vaccines a viable option in your personal war against cancer? It is very difficult to make an informed choice about Gardasil or Cervarix when you receive only part of the available information. The time has come to take a critical look at the facts behind recent HPV vaccine news reports.
In June 2006, the Advisory Committee on Immunization Practices (ACIP) recommended routine vaccination with 3 doses of Gardasil for females aged 11 or 12 years and catch-up vaccination for those 13 to 26 years old. In October 2009, this recommendation was updated to include Cervarix as an option for HPV (human papillomavirus) control.
The theory behind these two vaccines is: by reducing infections with the two high-risk types of HPV associated with an estimated 70% of cervical cancer cases globally, there may be a reduction in the number of cervical cancer victims. However, until such time as a verifiable reduction in the number of cervical cancer diagnoses is reported, this theory remains unproven.
HPV vaccines show striking results?
On June 19, 2013, the ACIP held a meeting via teleconference to discuss future HPV vaccination recommendations. During this teleconference Dr. Lauri Markowitz, CDC Division of STD Prevention, made a startling announcement. According to her research paper:1
“Among females aged 14-19 years, the vaccine-type HPV prevalence (HPV-6, -11, -16, or -18) decreased from 11.5% in 2003-2006 to 5.1% in 2007-2010, a decline of 56%.”
One has to wonder why a paper revealing such incredible findings was accepted for publication on April 3, 2013 but embargoed until the day of Dr. Markowitz’s grand announcement. This embargo did not seem to effect the speed at which the ‘news’ got out.
Almost the second the embargo was lifted the public was bombarded with articles singing the praises of the latest medical miracle – HPV vaccines. Virtually none of these articles cited or referenced the relevant publication. Those that did only provided access to the abstract.
Because of this oversight, neither medical professionals nor medical consumers are able to analyze the study for themselves and verify the glowing ‘facts’ reported in virtually every ‘news’ source across the country.
Any article published without providing a way to check facts and verify data is nothing more than free advertising for HPV vaccine manufacturers. Is this the purpose of the Press?
Take a look at the study behind the glowing news reports
In order to evaluate the quality of information in any scientific study, one must understand how the information was gathered, how large the sample size was, and whether the data presented is relevant to the study objective(s).
Information for the study conducted by Markowitz et al was taken from the NHANES database. Most people are completely unfamiliar with this source.
NHANES is the National Health and Nutrition Examination Survey. Information for this database is collected via personal interviews with specially selected individuals who are intended to be representative of large portions of the population. Each individual’s information is estimated to represent between 50,000 and 65,000 people.2, 3 Answers provided by the participants are not vetted for accuracy by examination of medical records. Information obtained on juveniles is not available to the general public, only CDC approved research scientists can gain access to it, and then only for approved research projects.
The interview is followed by a physical examination in a Mobile Examination Center (MEC).4 Of particular importance is the fact that HPV prevalence is determined via self-collected vaginal swab samples, then analyzed for HPV DNA using Digene Hybrid Capture and/or Roche Linear Array.4
CDC officials know, or should know, that the presence of HPV DNA in the vagina has little or nothing to do with the possibility of developing cervical cancer at a later date. CDC officials know, or should know, that it is virtually impossible for a woman to take an adequate cervical specimen themselves. In fact, the CDC site specifically states:
“While HC2 is approved for clinical testing, the self-collected vaginal sample does not meet clinical guidelines. The HPV PCR tests are research tests.”4
For the average medical consumer this brings up the following questions:
- Self-collected samples are not adequate for clinical use. Why are they adequate for research?
- HC2 (Hybrid Capture 2) is approved for use in doctor’s offices – but its accuracy is questionable. When 199 specimens were analyzed by three different laboratories using the same test, agreement on positive results varied from 54-78%.5 Is this percentage of accuracy adequate for your healthcare needs?
- HPV PCR (Roche Linear Array) is not approved for use by your doctor. Accuracy of this test is also questionable. When DNA sequencing was compared to the results of 102 linear array tests, 61% of the results did not match.6 Can you trust medical research based on 39% accuracy?
With these limitations in mind, let’s take a look at a few recent headlines touting the ‘phenomenal success’ of HPV vaccines.
Headlines versus Facts
Big Drop in HPV, Vaccine Gets Credit, by Charles Bankhead, Staff Writer, MedPage Today, June 19, 2013, stated:
“Compared with the 4 years prior to the vaccine’s introduction, infection with the HPV strains covered by the vaccine decreased by 56% in 14- to 19-year-old girls in the first 4 years after the vaccine became available.”
Facts: The article fails to mention that the vaccine-relevant HPV types being measured are based on estimates. NHANES data for 2003-2006 only broke HPV types down into low-risk versus high-risk types. There was no analysis of vaccine-relevant types of HPV versus other types in the 2003-2006 NHANES reports. This makes the study’s baseline prevalence data nothing more than an educated guess.
It also fails to mention the study contained only 111 subjects vaccinated against HPV. A person was considered ‘vaccinated’ if they had one or more injections. The CDC recommendation for HPV vaccines is three doses. According to the study, only 62.5% of those who reported HPV vaccinations received all three doses. This would mean there were only 69 fully vaccinated subjects included in the entire study population, approximately 19% of the 2007-2010 group. Is this a sample size large enough to draw conclusions from?
HPV Vaccine Is Credited in Fall of Teenagers’ Infection Rate, by Sabrina Tavernise, The New York Times, June 19, 2013, stated:
“Yet even with relatively low vaccination rates in the United States, infection with the viral strains that cause cancer dropped to 3.6 percent among girls ages 14 to 19 in 2010, from 7.2 percent in 2006, the officials said.
The infection rate for girls fell even further when the two strains of the virus that cause genital warts were included, with a 56 percent drop over the period of the study.”
Facts: This information is from table 1 of the study, comparing all of the subjects (ages 14-19) who were interviewed whether they reported being sexually active or not. This included 1363 girls in the 2003-2006 group and 740 girls in the 2007-2010 group.
Table 3 from the same study is a little more revealing. In this table, all of those who were not sexually active were eliminated. 46% were eliminated from the 2003-2006 group; 52% from the 2007-2010 group. Those who are not sexually active are much less likely to be exposed to HPV. This disparity alone could account for some of the decline in HPV prevalence.
Look at the data below from Table 3 of the study, where those who were not sexually active were excluded. Note: those who were not vaccinated experienced a larger decrease in HPV prevalence than those who were vaccinated in all but one category. So, why does the vaccine get the credit?
Table 3: HPV Prevalence Among Sexually Active Females Aged 14-19 Years, Overall and by Vaccination History
|Vaccine Type HPV
|High Risk non-vaccine type
It is interesting to note there is some evidence indicating potential type replacement demonstrated by the increased prevalence of high-risk HPV types which are not vaccine-relevant in those who were vaccinated. These high-risk types include alpha-7 and alpha-9 species. Vaccinated subjects experienced an increase in all three of the high-risk categories.
HPV vaccine reduces cancer virus in girls by 56%, by Elizabeth Weise, USA Today, June 19, 2013 states:
“Doctors aren’t sure why the decline is so great, given that only 46% of young women have received at least one dose and only 32% have received all three. It could be what’s called herd immunity, in which the vaccinated women lower the overall amount of the virus in the population, thus lowering infection rates for everyone, said Lauri Markowitz, lead author of the study.”
Facts: First, medical professionals and consumers need to understand that the quote above is referencing two different sources of data. The HPV vaccine uptake rates are from a document produced by the CDC entitled, “National and state vaccination coverage among adolescents aged 13 through 17-United States, 2010.” (MMWR 2011;60:1117-23). This document has nothing to do with the HPV vaccine uptake rate in those included in the NHANES data.
Among those counted in the NHANES data, the uptake rate for HPV vaccine uptake rate was only 34% receiving one or more doses. Those who were fully vaccinated represented only 19% of the age group in question.
With all due respect to author Elizabeth Weise, you cannot compare apples to oranges and make any sort of valid scientific conclusion.
According to Vaccines and Public Health, the CDC and WHO have estimated what vaccine coverage needed in order to confer ‘herd immunity’ for the following diseases:
- Diphtheria – 85%
- Pertussis – 92-94%
- Polio – 80-86%
- Measles – 83-94%
- Mumps – 75-86%
- Rubella – 83-85%
How can a representative of the CDC, or anyone else for that matter, even infer that a vaccine uptake between 19-34% would confer any sort of ‘herd immunity?’
It works: HPV vaccine reduces infections by 56%, CDC says, by Karen Kaplan, the Los Angeles Times, June 19 2013 states:
“Altogether, a total of 8,403 teens were tested for the four types of HPV — HPV-6, HPV-11, HPV-16 and HPV-18 — that are targeted by the vaccines. The 56% drop in HPV infection was found for females between the ages of 14 and 19.”
Facts: 8,403 people were included in the complete study – from 2003-2010 – ages from 14 to 59. Nearly half of those were not tested for type-specific vaccine-relevant HPV, the 4150 subjects from 2003-2006. The other 4253, from the 2007-2010 surveys, only included 740 teens.
There is evidence that a reduction in HPV infections did occur. Whether or not it had anything to do with HPV vaccines remains to be seen.
New study shows HPV vaccine helping lower HPV infection rates in teen girls, by Division of News & Electronic Media, Office of Communications, CDC press release quotes Dr. Tom Frieden, CDC Director, as saying:
“This report shows that HPV vaccine works well, and the report should be a wake-up call to our nation to protect the next generation by increasing HPV vaccination rates,” said CDC Director Tom Frieden, M.D., M.P.H. “Unfortunately only one third of girls aged 13-17 have been fully vaccinated with HPV vaccine. Countries such as Rwanda have vaccinated more than 80 percent of their teen girls. Our low vaccination rates represent 50,000 preventable tragedies – 50,000 girls alive today will develop cervical cancer over their lifetime that would have been prevented if we reach 80 percent vaccination rates. For every year we delay in doing so, another 4,400 girls will develop cervical cancer in their lifetimes.”
Facts: This report shows nothing of the sort. This report raises more questions than answers.
Respectfully, Dr. Frieden: the 50,000 preventable tragedies you speak of would never occur if women would go for their pap tests as recommended. Pap tests detect cervical cell changes BEFORE cancer begins to develop.
You mention Rwanda’s better than 80% uptake on HPV vaccines, but make no mention of any demonstrated reduction in the prevalence of vaccine-relevant HPV in that country. If the United States’ HPV ‘study’ you reference is accurate, Rwanda should have already eliminated nearly all vaccine-relevant HPV. Assuming this is true, it will still take another decade or two to determine if there is any impact on cervical cancer attributable to HPV vaccination programs.
Should all high-risk types of HPV be completely eliminated, that would simply mean one risk factor for cervical cancer would no longer be a part of the cervical cancer equation. The remaining risk factors would still be present.
Eliminating one risk factor does not justify the adverse events being experienced after HPV vaccines.
In the interest of public health and safety, the very least the CDC should do is be honest about the potential risks and refrain from exaggerating the potential benefits of HPV vaccines.
1) Reduction in Human Papillomavirus (HPV) prevalence Among Young Women Following HPV Vaccine Introduction in the United States, National Health and Nutrition Examination Surveys, 2003-2010, JID, Laurie E. Markowitz et al….
5) Accuracy and Interlaboratory Reliability of Human Papillomavirus DNA Testing by Hybrid Capture, Journal of Clinical Microbiology, Mar. 1995, p. 545–550
6) Comparison of DNA Sequencing and Roche Linear Array in Human papillomavirus (HPV) Genotyping, Laura Giuliani et al, Anticancer Research 26: 3939-3942 (2006)