Fears of Hepatitis Vaccine/Multiple Sclerosis Link Unfounded
Jan. 31, 2001 -- In 1901, bands of physicians roamed the streets of Boston, vaccinating "all who were willing and not too ill" against smallpox. The vaccine ultimately led to the worldwide eradication of smallpox, but hepatitis B and other infectious illnesses still pose a threat to us a hundred years later.
When the smallpox vaccine was introduced, some people did not understand how it worked or why it would be of value. Today, physicians are concerned that people who need certain vaccinations are not getting them, and they worry about children who might not be immunized because of unfounded fears about vaccine safety. As with smallpox, there is an effective vaccine to prevent hepatitis B, and two new studies now refute any suggestion that this vaccine can cause or worsen multiple sclerosis, or MS.
The U.S. government's top hepatitis official, other vaccine experts, and the author of one of the studies tell WebMD the findings are "reassuring" and should erase any fears that parents might have about vaccinating their children against hepatitis B. The studies, one from France and one from researchers at Harvard University in Boston, both appear in the Feb. 1 issue of The New England Journal of Medicine.
"What we needed were these kinds of studies that looked to see if there was a true association," says Harold S. Margolis, MD, chief of the hepatitis branch at the CDC in Atlanta. "There doesn't appear to be an association with the hepatitis B vaccine and MS, which was one of the allegations, and there is no evidence that it [worsens] the illness in people who already have MS. It should help in terms of providing information to the public and to patients that this is not something that is causing this particular disease."
Hepatitis B, carried by a virus, is the leading cause of liver cancer and cirrhosis of the liver. As many as 320,000 U.S. children and adults contract the illness each year, and many do not show the classic symptoms of jaundice, abdominal pain, loss of appetite, and vomiting; but they can still spread the infection. Worldwide, it is estimated that 350 million people are carriers of hepatitis B, and of those, an estimated 65 million will die of liver disease. The disease is spread through contact with infected blood, needles, or sexual encounters. It is 100 times more infectious than HIV, the virus that causes AIDS.
A vaccine against hepatitis B has been available since 1982, and since then infants and adolescents are routinely immunized. Groups that are at higher risk of contracting hepatitis B are also urged to get vaccinated; these groups include sexually active men and women, as well as healthcare workers. Pregnant women are screened for this disease because they can pass it on to their newborns.