Is the HPV Vaccine Gardasil Dangerous?

A viral Facebook post making such claims misrepresents some statistics and makes up others.

A viral Facebook post claimed that Gardasil, a human papillomavirus (HPV) vaccine, caused 40 deaths in its original clinical trials. The post further claims that aluminum was used as a placebo in the drug trials, “meaning all clinical trial participants were injected with a powerful neurotoxin.” The post alleges that aluminum was used so as “to try to make adverse events between the gardasil group and the 'placebo' group seem insignificant.” The alleged source of information for these claims is the manufacture package insert for Gardasil, which is linked to at the end of the post.

However, reading through the manufacture insert on the FDA’s website shows important context was left out: While 40 out of the 29,323 participants in the clinical trials did pass away, more than half of the causes of death have no connection with the vaccine. There were seven clinical trials performed, five of which used amorphous aluminum hydroxyphosphate sulfate (AAHS) for the control group placebo, one of which used a saline solution, and one of which had no control. The most common cause of death across these seven trials was car accidents, which resulted in the passing of nine participants. Another four died because of gunshot wounds. Eight participants died because of drug overdoses or suicide. And while some vaccination skeptics argue that those suicides and drug use could be due to the vaccine causing mental health issues, six of the participants who died because of overdose or suicide had taken the placebo. What’s more, Dr. Paul Offit, inventor of the rotavirus vaccine and an expert on vaccines and immunology at the Children’s Hospital of Philadelphia, told The Dispatch Fact Check that “Post-licensure studies have shown no increase in mental health problems."

Of the remaining 19 deaths, there was no consistency in the causes, with two participants passing away because of pulmonary embolism/deep vein thrombosis (one of whom took Gardasil, one of whom was given AAHS), two participants from the Gardasil group dying because of sepsis, and 10 others from the Gardasil group dying from 10 different health problems. Four from the AAHS control group died from four different health issues and one from the saline group died from medulloblastoma. The package insert notes that “The events reported were consistent with events expected in healthy adolescent and adult populations,” meaning that the deaths that occurred, and their causes, occur in these numbers in the general population as well.

The description of amorphous aluminum hydroxyphosphate sulfate as a “neurotoxin” is also incorrect. While aluminum can be toxic in high doses, the amount necessary for toxicity depends on how it is taken into the human body. For example, the Occupational Safety and Health Administration set a legal limit of 15 micrograms per cubic meter of total aluminum dust in the air averaged over an 8 hour work day,” but the Food and Drug Administration has set the limit for the amount present in bottled water as 0.2 milligrams per liter. The FDA limit for vaccines is 0.85 milligrams to 1.25 milligrams per dose. The amount of aluminum in vaccines is so low, that according to the Children’s Hospital of Philadelphia infants ingest more aluminum through their diet in their first six months than they do from all their recommended vaccines during that time. The AAHS control in the Gardasil clinical trials was 225 micrograms or .225 milligrams per dose, well below the FDA’s set limit.

AAHS is also commonly found in vaccines including Gardasil itself. AAHS is an adjuvant, an ingredient that's added to some vaccines that increases the immune response. Adjuvants are not present in all vaccines, but the boost they give the immune response helps prevent patients from catching whatever illness that they’re being vaccinated against from the vaccine itself. Adjuvants can cause some redness or swelling at the site of the injection and occasionally lead to minor side effects like fevers and body chills, but Offit noted that AAHS is so widely used because it leads to fewer side effects. “CpG motifs, QS-21, and monophosphoryl lipid A are more effective, but have a greater incidence of side effects,” said Offit. Aluminum salts have been used as adjuvants for more than 70 years without any serious side effects reported that would merit their discontinuation. 

Gardasil’s manufacturer label notes that each 0.5 milliliter dose “contains approximately 225 [micrograms] of aluminum.” Converting micrograms to milligrams, that comes out to .225 milligrams per dose. Two shots are recommended, the first at age 11 or 12 with the second shot being administered six to 12 months later, meaning the total amount of aluminum patients receive is .45 mg, just shy of the  0.5 mg of aluminum that the Children’s Hospital of Philadelphia reports for the HPV vaccine in general (that number is reflective of the three HPV vaccines licensed for use in U.S.).  

The Facebook post also notes that the company that manufactures Gardasil, Merck, was responsible for a drug called Vioxx, which the post alleges “was responsible for over 500,000 deaths.” This specific claim actually originated in 2012, when The American Conservative published an article alleging that a rise in the American death rate in 1999—when Vioxx was introduced—and a decline in the death rate in 2004—the year Merck took it off the market after a study of its own concluded the drug increased the risk of heart attacks and strokes—could mean the drug was responsible for the 500,000 additional deaths that occurred during that time period. The writer noted that “Patterns of cause and effect cannot easily be proven,” and said that he was “hypothesiz[ing] a direct connection” between Vioxx and the deaths. A non-peer-reviewed study performed by an FDA scientist found a possible link between Vioxx and serious cardiovascular events, but arrived at a much lower number. By comparing the number of heart attacks and deaths of individuals taking Vioxx to those on a competing brand called Celebrex, the study projected the drug may have been responsible for 27,785 heart attacks and sudden cardiac deaths, though that number does not tell us how many of the heart attacks were nonfatal. 

The Facebook post correctly notes that the control group in clinical trials for Gardasil 9 was administered Gardasil, but also claims that “There is the frightening connection between the gardasil shot and loss of pregnancy. According to the Gardasil 9 package insert, 1,028 women who were injected with Gardasil 9 became pregnant during the course of the clinical trials. A total of 313 women either lost their babies to spontaneous fetal death or late fetal death or gave birth to children with congenital anomalies.” The HPV vaccine is not recommended for pregnant women because as the CDC states: “Studies show that the HPV vaccine does not cause problems for babies born to women who were vaccinated while pregnant, but more research is still needed.” The post links to the packaging insert, which does not say anywhere that 1,028 women in the clinical trials became pregnant or that 313 of those women lost their babies or gave birth to a child with birth defects. Given the uncertainty about the safety of receiving the HPV vaccine while pregnant, Merck gave pregnancy tests to female participants before every dose in clinical trials for both Gardasil and Gardasil 9. Those who had a positive test were not administered the vaccine dose and were told to wait until after they gave birth to receive the vaccination or complete it if a dose had already been received. Despite these tests, some women were given the vaccine very early in their pregnancies, before tests could accurately determine that they were pregnant. Of pregnancies that were onset within 30 days before or after participants were given the vaccine, the Gardasil 9 insert says that there were 117 pregnancies—not 1,028—with a known outcome. That number excludes ectopic pregnancies and elective abortions. In all, 62 pregnancies occurred among women who were administered Gardasil 9, of which 17 ended in a miscarraige. Further,  55 pregnancies occurred in the control group that was administered Gardasil, of which seven ended in a miscarraige. None of the children from the Gardasil 9 group had birth defects and only one from the Gardasil control group did. 

Despite what this Facebook post and others may claim, the HPV vaccine is considered safe and yields great benefits. As the CDC states on its website: “Over 12 years of monitoring and research have shown that HPV vaccination is very safe. Each HPV vaccine—Gardasil® 9, Gardasil®, and Cervarix®—went through years of extensive safety testing before they were licensed by the U.S. Food and Drug Administration (FDA). FDA only licenses a vaccine if it is safe, effective, and the benefits outweigh the risks.” Men and women who receive the HPV vaccine see a lower incidence of genital warts and HPV infections that lead to cancer, and women who have had the vaccine administered see a 40 percent drop in cervical pre-cancers compared with the general population. Claims that the HPV vaccine is dangerous are based on a misreading of data or outright fabrication.

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