Large study supports safety of Gardasil HPV vaccine

A study published in Archives of Pediatrics & Adolescent Medicine affirms the safety of the HPV quadrivalent vaccine, also known as Gardasil (or Silgard in Europe). The vaccine prevents infection by human papillomavirus, a sexually transmitted disease, its subtypes 16 and 18 not only cause approximately 70% of cervical cancers, but they cause most HPV-induced anal (95% linked to HPV), vulvar (50% linked), vaginal (65% linked), oropharyngeal (60% linked) and penile (35% linked) cancers. The viruses are generally passed through genital contact, almost always as a result of vaginal, oral and anal sex.

There is strong clinical evidence that the incidence of HPV infections have declined since the launch of the HPV vaccine and the subsequent steady rate of HPV vaccination.

The large study, which included nearly 200,000 young females who had received the vaccine, found that the vaccine was only associated  with same-day syncope (fainting) and skin infections in the two weeks after vaccination. These findings support other large studies that also found the vaccine safe and an appropriate strategy to prevent cervical cancers. The authors stated that, “this study did not detect evidence of new safety concerns among females 9 to 26 years of age secondary to vaccination with HPV4.”

In an article in Science News, lead author Nicola Klein, MD, PhD, co-director and research scientist at the Kaiser Permanente Vaccine Study Center in Oakland, Calif, stated that,”taking into account all the analyses, subanalyses and relevant medical record reviews, an independent safety committee noted that there may be an association between HPV4 vaccination and same-day syncope, as well as skin infections during the two weeks after immunization.”  Fainting is not an unexpected result with vaccinations reported the authors, because injections of all types are correlated with fainting.

The study’s strengths, a large, ethnically diverse population who received a total of nearly 350,000 HPV4 doses; an integrated health care delivery system (Kaiser-Permanente) that assured complete or near-complete medical information and follow-up; and a “pre-specified, validated, clinically meaningful system to categorize all outcomes.”

This study is powered in a way to find causal links to vaccinations as opposed to anecdotes, since patients are closely monitored after the vaccinations. The results strongly confirm the safety of this important vaccine and set aside the rumors and gossip that have floated across the internet about Gardasil.

Let’s repeat what was found in this study. 350,000 doses given. The only adverse reactions were fainting, an expected outcome from any needle injection, and skin infection, another expected (and preventable) outcome. So, in a well controlled study, where the patients could be observed carefully in a modern healthcare environment, no dangerous adverse events were observed. A vaccine that can prevent cancers–dangerous, life-threatening cancers–is safe. 

So, who are you going to believe, a website that publishes anecdotes, or worse yet, lies? Or a huge, scientific study published in the Journal of the American Medical Association, one of the premier medical journals in the world? Unless you prefer pseudoscience, the answer should be easy.

Gardasil Saves Lives. 


If you need to search for scientific information and evidence about vaccines try the Science-based Vaccine Search Engine.


Key citations:

The Original Skeptical Raptor
Chief Executive Officer at SkepticalRaptor
Lifetime lover of science, especially biomedical research. Spent years in academics, business development, research, and traveling the world shilling for Big Pharma. I love sports, mostly college basketball and football, hockey, and baseball. I enjoy great food and intelligent conversation. And a delicious morning coffee!