This article has a great explanation of a 2010 meta-analysis of all epidemiological studies! The conclusion — well, my title says it all!
Category Archives: Science
Today Dr. Mercola posted an article called, “Don’t Give This to Your Daughter – Despite What Your Doctor Says.” When I saw his article in my newsfeed, I immediately read it. While interesting, several of his points are somewhat inaccurate and misrepresent the true evidence. Vaccination is a contentious issue, and it’s important to understand the scientific literature out there. Please do not jump to conclusions based simply on the timing of onset of health issues. The Paleo community sometimes has a tendency to place too much faith in the philosophy that living like a caveman means rejecting accepted medical wisdom. Take a step back and consider the evidence:
1. Adverse Events:
Dr. Mercola cites the 23,000 Gardasil-related adverse events in the Vaccine Adverse Events Reporting System (VAERS), a website database with unverified reports of adverse events. Any individual can go on this website and report a supposed negative side effect of the drug. Here’s how this works: remember when people thought Autism Spectrum Disorders resulted from the childhood MMR vaccine? Well, this fact has been 100% proven to be false, with the initial study completely discredited. I won’t get into that here, but my point is, people jump to conclusions rather easily when their children’s health is at stake. Fainting has been associated to a small extent with the vaccination, as has minor infection, but “no serious adverse effects occurred” in a 60-day follow-up study published in the journal Archives of Pediatrics and Adolescent Medicine (http://www.landesbioscience.com/journals/vaccines/ 2012HV0811N.pdf). I could go on and on with study after study NOT funded by industry, but it would be a waste of all of our time. Here’s the real data: True scientific literature all reports that side effects associated with Gardasil are mild (http://www.ncbi.nlm.nih.gov/pubmed/19283255). When the events that are self-reported on the above website are analyzed by independent researchers, they are largely found to be unrelated to the vaccination in question.
2. Claim That Infection Is Not Harmful:
Dr. Mercola says that “As a vaccine for children, it doesn’t make sense to vaccinate to try to prevent an infection that is cleared from your body without any negative effects within two years in most healthy persons.” Now, he is completely right that education is one of the most important aspects of prevention, which we all believe is key in medicine. No one is disagreeing that many people are infected with HPV at some point in their lives. In fact, 50% of sexually active individuals will contract it at some point in their lives (http://www.cdc.gov/std/HPV/STDFact-HPV.htm). The problem is not HPV itself, although genital warts sound pretty unpleasant, but the fact that almost all cervical cancer is HPV-related. Cervical cancer is the third most common cancer worldwide, and 80% of cases occur in the developing world, where it causes hundreds of thousands of preventable deaths each year. Remember, vaccination is not only about individual protection. We need to think of individuals outside of the US and associated developed countries, where sexual education is infinitely better than elsewhere (despite its shortcomings).
3. Gardasil Is NOT Designed to Protect Against Only Two Strains
Here Dr. Mercola is flat-out wrong, no sugar-coating. In reality, Gardasil is a “quadrivalent” vaccine, meaning it protectas against 4 strains of HPV. Dr. Mercola is thinking of a different brand of the vaccine, but he should get his facts straight before making extreme claims about the safety and efficacy of a vaccination, as many individuals will take his word rather than conducting research on their own. I would FURTHER add that 70% of cervical carcinomas are caused by HPV-16 and -18, so EVEN if it was JUST those two strains (as is GlaxoSmithKline’s version), this fact would not diminish the relevance of HPV vaccination (http://www.ncbi.nlm.nih.gov/pubmed/21289891). Just for reference and to make sure you understand that I know the distinction, 90% of genital warts cases are caused by HPV-6 and -11 (development of warts and carcinoma is not symmetrical) (http://jid.oxfordjournals.org/content/ 206/6/860.abstract). Keep in mind also that there is also a degree of cross-protection in the vaccine for other strains as well.
4. The Waning of Gardasil-Induced Immunity
One point of Dr. Mercola’s that I will grant is that the efficacy of the vaccine in preventing cervical cancer that may develop 20-40 years post-vaccination has not been established. That said, I would like to point out that young women are at the highest risk for HPV infection, and Gardasil protects them during this vulnerable stage of their lives. In fact, prevalence of HPV infection ishighest among females age 20 to 24 years (44.8 percent) (http://www.medical newstoday.com/releases/64119.php).
No one disagrees that in many circles the vaccine is mis-represented. Yes, education is important, and people need to understand what HPV is and how it relates to cervical cancer. This point is rather tangential to whether or not women/men should be vaccinated. I could have an entire post on the public information regarding the vaccine.
6. Efficacy Based on Age
The HPV vaccination is indeed more effective in younger individuals, who are less likely to have had sexual partners and been exposed to any strain of the virus. While not worthless among adults with more sexual partners, these individuals will be less protected — that’s all. No one disagrees here. (http://www.ncbi.nlm.nih.gov/pubmed/ 23199956). Again, none of this means that we shouldn’t vaccinate.
Intermediate outcomes are a necessary measure in science. Once a vaccine or treatment is available, it is rarely put “on hold” because follow-up was limited to 5 years rather than 20, especially when alternatives are not available. In the case of HPV, “high-grade cervical lesions” are considered a reliable predictor of increased probability for the development of invasive cancer, which can take years after infection to become clinically detectable. Would we never have started using penicillin if we had to wait 20-40 years before seeing whether or not it had any adverse effects? Sometimes scientifically plausible links need to be established, at least in the interim and when justifiable according to the evidence.
Some strong supporting evidence:
Australia was the first country to implement a universal government-funded HPV vaccination program. When Australia provided free quadrivalent HPV vaccination to girls aged 12-18 between mid-2007 and the the end of 2009, diagnosis of genital warts in new patients to the Melbourne Sexual Health Centre declined in women under age 21 from 18.6% to 1.9%. In woman over 30 (who did not receive free vaccination), there was no change (not exactly a “control” but as close as ethically possible). Analysis was adjusted for the number of sexual partners, which might otherwise have been a confounding factor. Furthermore, prevalence of other STIs in the clinic continued to increase, coinciding with the “expected” trend, which would seem to indicate that the decreased prevalence of genital warts was not coincidental (http://sti.bmj.com/content/87/7/544.long). The same trend was observed in a Swedish study, among others (http://jid.oxfordjournals.org/content/206/6/860.abstract).
In New Zealand, a similar program was initiated in 2008. Between 2007 and 2010, the rates of genital warts in women under 20 years who visited the Auckland Sexual Health Service decreased from 13.7% to 5.1%. In women over 20 the decrease was 7.6% to 5.9%. (http://www.ncbi.nlm.nih.gov/pubmed/21952330)
Anyway, I could go on and on. The HPV vaccine pushed us forward leaps and bounds, and made an immense difference in the prevalence of HPV in many parts of the world. Only time will tell whether cervical cancer diagnoses diminish, but all scientific evidence points toward the expectation that it will. Please do not let your fear of the unknown lead you to accept vaccination paranoia. In one social psychology experiment, researchers went around telling people that “dihydrogen monoxide” was slowly poisoning everyone, and asked individuals to sign a petition for its ban. Not knowing that H2O is water, nearly everyone signed. Don’t make the same mistake when thinking about the science behind vaccinations like Gardasil.