PASADENA, Calif. — A human papillomavirus vaccine created by drug maker Merck does not cause autoimmune conditions after young women are inoculated, according to a new Kaiser Permanente study.
Researchers used electronic health records to conduct an observational safety study of 189,629 females ages 9 to 26 years in California who were followed for six months after receiving each dose of Gardasil, the quadrivalent HPV vaccine, from 2006 to 2008. The study looked for autoimmune conditions — such as immune thrombocytopenia, autoimmune hemolytic anemia, systemic lupus erythematosus, rheumatoid arthritis, juvenile rheumatoid arthritis, Type 1 diabetes, Hashimoto's disease, Graves' disease, multiple sclerosis, acute disseminated encephalomyelitis, other demyelinating diseases of the central nervous system, vaccine-associated demyelination, Guillain-Barre syndrome, neuromyelitis optica, optic neuritis and uveitis — since autoimmune reactions have been a long-standing concern surrounding vaccination and many parents withhold the vaccine from their children because of perceived safety concerns, the researchers noted.
"This kind of safety information may help parents with vaccination decisions," said study lead author Chun Chao, a research scientist at the Kaiser Permanente Department of Research & Evaluation in Pasadena, Calif. "These findings offer some assurance that among a large and generalizable female population, no safety signal for autoimmune conditions was found following HPV4 vaccination in routine clinical use."
The study, funded by Merck, appears in the Journal of Internal Medicine.