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Hepatitis Vaccine Safety Questioned
Some parents resist required B virus shot for infants, but health officials say
risk slight
Taken from http://www.austin360.com/news/002state/11nov/30/30vaccines.htm
By Andrew Park
American-Statesman Staff
Published: Nov. 30, 1998
The statistics say Pamela Daviscourt is crazy to worry about the hepatitis B shot the State of Texas
wants to give her 20-month-old son.
Only about 22,000 of the 20 million people in the United States vaccinated against the virus have
reported bad reactions to it, and no one knows whether those reactions were even caused by the
shots.
But Daviscourt doesn't think she's crazy to hold off. Infants have little chance of catching the
virus except from their mothers, and she doesn't have hepatitis B.
Still, why not give the boy the vaccine, which he'll eventually need to enter public school here?
The issue, she said, is safety. She said she fears the vaccine carries more risks than benefits.
"My approach has been to feed my child as nutritionally as possible and keep his immune system
up," said Daviscourt, who recently moved to Austin from Washington state. "I just believe
if his immune system is strong, he is going to be resistant to anything out there."
Unlike some opponents of immunization programs, Daviscourt harbors no religious or political
objection to vaccinating her child, just concern about recent reports of bad reactions to the
hepatitis B vaccine. A small number of people have developed arthritis, chronic fatigue, symptoms of
multiple sclerosis and other conditions after taking the shot. Similar reports in France brought
that country's hepatitis B immunization program to a halt last month.
In Texas, the state Health Department receives at least 50 to 60 reports each year from people who
have suffered health problems after being immunized for hepatitis B, ranging in seriousness from
headaches to deaths. Officials say they have no way of knowing whether those reactions were caused
by, or even related to, the vaccine.
"Though no vaccine is risk-free, the hepatitis B is one of the safest," said Sharon
Duncan, hepatitis coordinator at the Texas Department of Health. "The benefits outweigh the
risk. We do believe that it is safe."
The department recommends that all newborns and children up to the age of 12 be vaccinated against
hepatitis B, which can lead to chronic liver diseases, including cancer. This year, all children
entering public school in Texas had to be immunized against hepatitis B, and the shots were offered
to seventh-graders in Austin public schools this month.
The effort did not come about because hepatitis B poses great risks to children. The virus is
primarily transmitted among adults who have unprotected sex, share drug needles or are exposed to
contaminated blood. There is also evidence that it can be passed through saliva and tears and from a
mother to a child in the womb. Locally, only a few cases of hepatitis B in children are reported
each year.
Still, immunizing all infants is widely considered the only way to protect against an outbreak of
the disease. Health departments complain that they cannot get teen-agers and adults to be vaccinated
once they have begun risky behavior or other exposure to the virus. Better to immunize them while
they're young and receiving other vaccines, the logic goes, and it's an argument supported by the
American Academy of Pediatrics, the Centers for Disease Control and Prevention and the World Health
Organization.
Baylor College of Medicine immunologist Bonnie Dunbar also believes in universal immunizations and
has worked for two decades developing vaccines to protect public health. But since watching two
people suffer neurological failures after taking the hepatitis B vaccine, she has spoken out against
its further use.
The vaccine, developed by drug companies Merck and Co. and SmithKline Beecham, was the first
recombinant DNA vaccine put on the market in the United States. Unlike conventional vaccines for
measles, mumps and polio, the genetically engineered hepatitis B shot does not contain a live form
of the virus. Theoretically, the shot won't give you hepatitis B, as sometimes happens with vaccines
that contain a live virus. But Dunbar is convinced that in some people, a protein in the recombinant
mixture triggers an autoimmune reaction, provoking the body to attack its own nerves and tissue.
She has cataloged more than 100 cases of autoimmune disorders found by other scientists, but she can
recall two other cases from memory: her brother, whose rashes, joint pain and chronic fatigue have
been determined to be side effects of the hepatitis B vaccine; and one of her students, who suffered
temporary blindness in one eye and deteriorating eyesight in the other after taking the shot. The
CDC and both drug companies acknowledge hearing of similar cases, but they call them extremely rare.
Dunbar worries that newborns who are given the vaccine are even more vulnerable to that risk because
of their less formidable defenses. Under Merck guidelines, newborns and teen-agers receive the same
dose of the vaccine.
"We know from our animal lab experiments that the immune system of the neonate is very
different from the adult," Dunbar said. "It has to be studied."
The CDC says it's looking into the effects of the vaccine and will have results to report next year.
Drug companies are also trying to determine how long the immune response to the vaccine lasts before
booster shots are needed. That has yet to be established.
In the meantime, a growing number of Texas parents are resisting the state's effort.
Some physicians worried about the effect on infants advise expectant mothers to decline the
hepatitis B vaccine when they arrive at the hospital to give birth. Other physicians sign one-year
medical exemptions that allow children of concerned parents to enter school without the shots.
Many parents opt to apply for an exemption that allows a permanent out for children whose families
believe in the anti-vaccine tenets of certain religions. Others have joined a Cedar Park group,
Parents Requesting Open Vaccine Education, that has lobbied the Legislature and the state Health
Department for more information about the hepatitis B vaccine before its use is expanded.
Still, pushing against the vaccine's momentum is not easy.
"I just felt such pressure," said Terri McDermott, an Austin mother who refused to have
her son vaccinated for hepatitis B when he was born in June. "I think had I not said, 'I'm
following up with my own doctor,' if I didn't basically have some excuse, then I would have been
pressured into doing it."
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