Press Releases

2001 Releases

Study Finds No Link Between Hepatitis B Vaccine and Risk of Multiple Sclerosis

For immediate release: January 31, 2001

Boston, MA. – A research team led by Alberto Ascherio, associate professor of epidemiology and nutrition at the Harvard School of Public Health, has conducted an investigation involving participants from two large on-going studies and found no association between the hepatitis B vaccine and the development of multiple sclerosis. The study results will be published in the February 1, New England Journal of Medicine (

The purpose of the HSPH study was to determine whether hepatitis B vaccine increases the risk of multiple sclerosis in previously healthy people. There had been particular concerns from Europe, where the French government decided to temporarily suspend school-based hepatitis B vaccines in 1998 after several cases of multiple sclerosis were reported a few weeks after the vaccine had been administered in 1995 and 1997 as part of a mass immunization program. Multiple sclerosis is a chronic degenerative disease of the central nervous system.

Participants for the HSPH study were drawn from the Nurses’ Health Study, which began in 1976 and the Nurses’ Health Study II, which started in 1989. Combined, the two on-going studies have tracked the health of more than 230,000 nurses for over two decades. The participants were drawn from the two studies because of the high prevalence among nurses of immunization with the hepatitis B vaccine and the availability of vaccination confirmation records from the nurses’ employers.

Following a rigorous screening process, 192 women with multiple sclerosis (MS) and 645 matched controls were selected from the two Nurses’ Health Studies by the researchers. For each woman with MS, five healthy women and one woman with breast cancer were selected as the controls. The number of doses of hepatitis B vaccine that the women with MS and the control women had received prior to the study’s starting point was similar, and a large percentage had received multiple doses of the vaccine.

The authors conclude that alterations in hepatitis B vaccination policies are not warranted and that changes could compromise or delay control of the disease. Lead author Alberto Ascherio said, "The study’s results appear to contradict previous concerns raised in other research and justifies keeping hepatitis B vaccination programs and policies firmly in place."

The study "Hepatitis B Vaccination and Risk of Multiple Sclerosis," was conducted by the Departments of Epidemiology and Nutrition at the Harvard School of Public Health, the Multiple Sclerosis Unit, the Center for Neurological Diseases at the Brigham and Women’s Hospital, the Harvard Medical School, and Merck Research Laboratories, West Point, PA.

The study was supported by grants from the National Institutes of Health and by Merck Research Laboratories.

For further information, please contact:

Robin Herman
Office of Communications
Harvard School of Public Health
677 Huntington Avenue
Boston, MA 02115
Phone: 617-432-4752