Both the timing of the symptoms and autopsy results “suggest a link between” the Gardasil vaccine and the fatal cases of amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, says Catherine Lomen-Hoerth, MD, director of the ALS Center at University of California San Francisco Medical Center.
With only two confirmed cases, “we don’t know for sure if it’s coincidence or if they’re connected [to the vaccine],” she tells WebMD. “We hope that by raising awareness, we will become aware of any other cases."
Pam Eisele, a spokeswoman for Merck & Co., which makes the vaccine, says the company cannot comment specifically on the cases as it has not seen the data.
“However, after carefully reviewing all the information available to us about reported adverse events, including reports of deaths, Merck does not believe these events have been caused by Gardasil,” she says.
The vaccine has been given to more than 7 million girls and young women nationwide.
Gardasil and ALS: Jenny’s Story
The tragic story of one of the girls, Jenny Tetlock, is chronicled on “Jenny’s Journey,” a web site created by her parents to publicize her case and get others with similar symptoms to come forward.
The first sign that something was wrong was when 14-year-old Jenny tripped on a hurdle that others in her class cleared easily, according to the web site. That was just months after her third and final booster Gardasil shot, Lomen-Hoerth says.
The disease rapidly progressed; both her legs, and then her arms became weak, Lomen-Hoerth continues. Jenny began to limp and had trouble gripping objects. She felt pins and needles in her feet, and her muscles atrophied, she tells WebMD.
Within a year, Jenny was paralyzed, a quadriplegic breathing only with the help of life support. She died shortly afterward, Lomen-Hoerth says.
Throughout the course of her illness, Jenny’s mind was as sharp as ever, she adds.
The other patient, a 20-year-old, developed similar symptoms within four months of her first Gardasil shot, Lomen-Hoerth says. The disease followed a similar course, and the girl died 28 months later.
Rapidly Progressive Course
In addition to the short time span between vaccination and the onset of symptoms, several other factors made the researchers suspect a link to Gardasil vaccination, Lomen-Hoerth says.
In both young women, the disease progressed more quickly than typical for young ALS patients, she says.
Additionally, at autopsy, “we were surprised that the spinal cord was so inflammatory. That is very different from what we normally see in ALS,” she says.
The pathology features “all support a temporal association between [the illness] and vaccination,” Lomen-Hoerth says.
She spoke at the annual meeting of the American Neurological Association.
Because it is extremely rare, affecting just one in 2-3 million young people, there are very few studies of juvenile ALS, Lomen-Hoerth says.
Her team plans further study comparing the symptoms and pathological features of young adults with ALS who got the Gardasil vaccine to those who didn’t get the shots. “If the features are identical, then we’ll know [the vaccine] is not the cause,” Lomen-Hoerth says.
In the meantime, she and colleagues have met with scientists from the FDA and CDC to scour their adverse-event database, called the Vaccine Adverse Event Reporting System (VAERS), for any other reports linking ALS to Gardasil or other vaccinations. “So far, we haven’t found any,” she says.
Merck is also continuing to work with the CDC and FDA to monitor any adverse events that may have been caused by the vaccine, according to Eisele.
Yadollah Harati, MD, a neurologist at Baylor College of Medicine in Houston, says the findings raise a red flag.
The fact that “the postmortem studies show distinct immunological features different from what is typical of ALS” suggest an association between vaccination and ALS, he says.
“I will be asking any of my young patients with ALS whether they received the Gardasil vaccine,” he tells WebMD. “I have one 20-year old ALS patient, and we didn’t think to ask that.”