May 30
By Maggie Fox, Health and Science Correspondent
WASHINGTON (Reuters) - The hepatitis B vaccine does not cause
multiple sclerosis or related neurological disorders, and it prevents a
serious infection that can cause fatal liver cancer, experts said on
Thursday.
The report, issued by the Institute of Medicine, is the third in a
series of reports by experts who are looking at vaccines to see if they
may cause serious side-effects in the population.
Hepatitis B is a virus transmitted in body fluids, and can be passed
on sexually, by sharing needles, in hospitals or via transfusions. It
can damage the liver and even cause liver cancer, liver failure and
death.
More than 1 billion people worldwide are infected, and one in 20
Americans carries the virus. U.S. children are now routinely vaccinated
against the virus because of the risk.
But some people have feared the vaccine may cause serious
side-effects, including the development of multiple sclerosis.
MS is caused when the immune system, for unknown reasons, attacks the
nerve fibers. It can cause fatigue and eventually completely debilitate
a patient. MS affects as estimated 300,000 Americans.
The hepatitis B vaccine has also been linked with Guillain-Barre
syndrome, a somewhat similar disease that affects 100,000 people.
Such diseases affect the myelin, the fatty coating of the nerves.
When it is stripped off, the nerves cannot conduct their electrical
signals properly and patients lose movement and coordination.
"Hepatitis B vaccine policy has been viewed skeptically by some
because of concerns about vaccine safety and a perception that the virus
itself does not pose a serious risk," Dr. Marie McCormick of the Harvard
School of Public Health, who led the study, said in a statement.
NO STRONG EVIDENCE
She said her committee of 14 experts held meetings and reviewed
studies. They heard about how serious hepatitis B is, and looked at the
purported way that the vaccine could cause MS and other neurological
disorders.
They found no strong evidence to suggest the vaccination could cause
such diseases, but recommended that experts keep an eye on their pattern
and incidence.
"Hopefully our report will ease the concerns of adults who need to be
immunized against hepatitis B and are worried about the risk of multiple
sclerosis," McCormick said.
The Centers for Disease Control and Prevention estimates that without
widespread vaccination, more than 18,000 U.S. children would have been
infected with hepatitis B and 3,000 would have eventually died from
cirrhosis or liver cancer.
The Institute of Medicine, one of the National Academies of Sciences,
was set up to advise the U.S. government on health issues. In February
McCormick's panel found no link between multiple childhood vaccinations
and type I diabetes, pneumonia, meningitis or other infections.
Last year it reported no strong evidence that the combined measles,
mumps and rubella vaccine may cause autism.
Some activist groups campaign against routine vaccination, saying the
risks are too high, but doctors are united in saying immunization has
saved millions of lives and transformed medicine. Side-effects are
inevitable, they say, but rare, and much less serious than the risk of
disease.
Copyright 2002 Reuters News Service. All rights reserved. This
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