In fact, the FDA’s safety information for the vaccine lists syncope, which is a form of fainting or paralysis, with clonic-tonic jerking and a seizure-like activity as a possible side effect.  It falls short of specifically naming seizures.

In the FDA’s vaccine adverse event reporting system, seizure cluster, seizure anoxic, clonic-tonic convulsions and seizure like phenomenon have been reported 75 times since Gardisil become available through March 2014.

In total, the FDA has catalogued 31,015 adverse events in VAERS, with 127 indicating death and another 556 categorized as life-threatening.

As of March 2013, the Department of Health and Human Services paid 49 claims totaling $5,877,710.87 for HPV vaccines as part of the government’s vaccine injury compensation program.

In Japan, the reports of adverse events were enough for the Ministry of Health to remove its proactive recommendation for the vaccine last June while the adverse events are investigated further.

But according to the FDA, the events listed in the database are not necessarily directly linked with any vaccine.

"People have put a timeline to them and said that they are biologically plausible, but we can't say for sure if they did or didn't happen directly because of the vaccine," said Dr. Diane Harper, the department chair of family and geriatric medicine at the University of Louisville.

Harper was part of a team of independent researchers who ran the clinical trials for Merck before Gardisil’s approval.

Since then, Harper has become an outspoken opponent about the drug, appearing in several nationally televised interviews to warn parents to do their research before deciding to inject their children.

Her main complaint, though, is not in regard to the potential side effects, it is regarding the effectiveness of the vaccine.

According to Harper, Merck does not have enough evidence to suggest that Gardisil will protect against HPV for longer than five years.  She said Merck knew this after its initial research but fast-tracked the drug for marketing anyways.

"They knew that they were defective.  They knew that they were limited and their vaccine had very little cross protection to other types," she said.

A study from 2010 suggests that Gardisil’s protection against HPV 18 wanes after four years, but according to a Merck representative, the drug has been proven effective up to eight years.

But Harper contends Merck is bringing about their next generation HPV vaccine,  the experimental V503, because they needed to develop some type of booster shot for the original vaccine.  She said the drug maker will gloss over the shortcomings of Gardisil by promoting the new vaccine with additional HPV protections.  V503 has been being researched since 2007 and is now in the third phase of clinical studies.

Although the FDA would not comment on its approval process of this drug, a Merck representative said the company anticipates U.S. regulatory action within the next year. 

Harper’s main concern is the number of antigens in the new vaccine. 

She pointed out the GaloxoSmithKline drug Cervarix, which guards against the main two cancer-causing strains of HPV and has far less antigens than both Gardisil and V503.

In an email, a Merck representative said the new drug will guard against 90 percent of cancer-causing HPV types, as well as 80 percent of high-grade cervical dysplasias and also some vaginal, vulvar and anal cancers.

“When one thinks about the ability to prevent a disease from happening, which is what we'd love for all of our loved ones, I think the more we can do in that arena, the better off we'd be as a society,” said Dr. Veronica Schimp, the chief gynecological oncologist at the University of Florida Cancer Center at Orlando Health. 

Schimp is a proponent of the Gardisil vaccine and pointed out that Cervarix has not been approved in boys.