Parents Should Know Both the Benefits and Risks of Vaccinations
By ERIC L. HURWITZ
According to recent medical findings, many parents
believe that childhood vaccines are unsafe and seek exemptions from school
mandates. Because unvaccinated children put themselves and others at greater
risk of highly contagious diseases that can be prevented by vaccines, it
is worth exploring the possible origins of these beliefs and whether they
are scientifically justified.
If vaccines cause harm to some children, and if
we cannot accurately predict which kids will be hurt, then mass vaccination
programs, by necessity, protect the public's health at their expense. Should
the risks and benefits to the child and the public of receiving or not
receiving each vaccine be disclosed by a physician in a way that the parent
understands the inherent uncertainty of risk and voluntarily makes a decision
to accept or refuse the vaccinations?
In the U.S., vaccine safety has historically taken
a back seat to development and rapid deployment. Remarkably, even today,
we lack procedures for the systematic collection of valid long-term safety
data. Documented cases of abuse of power, unethical studies and vaccine-induced
injury and death may contribute to parents' conceptions.
Evidence of conflicts of interest involving U.S.
Food and Drug Administration advisory panel members, the withdrawal of
the recently approved vaccine for rotavirus (responsible for severe diarrhea),
changes in the hepatitis B vaccine schedule because of possible harm from
a mercury-containing preservative and reports from the Institute of Medicine
are also likely reasons for concern. The institute concluded that the measles-mumps-rubella
and hepatitis B vaccines may cause anaphylaxis, a life-threatening allergic
reaction, and the causes of many other adverse outcomes could not be determined
because of insufficient data.
Moreover, a recent study suggests that the most
widely used current vaccines for whooping cough may be linked with anaphylaxis,
while surveillance of the chickenpox vaccine revealed anaphylaxis, encephalopathy
(a disorder affecting the brain) and other reactions. Links of the measles-mumps-rubella
vaccine and other immunizations with autism have been neither proved nor
disproved because of inadequate data.
Similarly, little is known about the potential long-term
consequences of multiple and combination vaccines typically administered
to American children. Findings from both animal and human studies suggest
that vaccinations are one of many genetic and environmental factors that
contribute to the increase in allergic disease. Thus, because of how vaccines
are tested and marketed, without large, long-term pre-approved safety studies
before widespread public school use, lack of confidence in vaccine safety
may not be a misconception, but a scientifically justifiable concern.
In fact, written informed consent may be warranted
because there is insufficient data to accurately estimate the risks; current
investigatory systems are not designed to assess the risks of rare events
or adverse outcomes with long latent periods; and post-marketing surveillance
is arguably research as defined by U.S. code. Because mandatory immunization
policies preclude voluntary informed consent, there is in many cases a
lack of trust and shared decision-making between parents and their child's
physician.
Any potential unintended consequences of current
and future vaccinations need to be acknowledged and adequately addressed
through the sharing of data, resources and expertise by government agencies,
vaccine manufacturers, researchers and policymakers.
Until we can predict which children are at risk
from current and future vaccines, voluntary, written informed consent rather
than coercion through mandates may help to restore parents' trust and maintain
the public's health.
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Eric L. Hurwitz Is an Assistant Professor at UCLA's School of Public
Health, Department of Epidemiology
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Letters to the Editor in response to commentary:
Los Angeles Times
Sunday, February 4, 2001
Childhood Vaccines
Eric L. Hurwitz's Jan. 30 commentary on vaccinations
was well-titled ("Parents Should Know Both the Benefits and Risks of Vaccinations")
but quickly lost focus. The balancing of medical risks is one of the hardest
things for a doctor to explain to a new parent. Asking parents to sign
consent forms is not a bad idea, but consent is not the same thing as informed
consent.
No vaccine carries a 100% guarantee of safety.
While parents need to know the risks involved in any vaccination, they
also ought to know the risks in not vaccinating: epidemics of infectious
disease. The United Kingdom has a rising number of measles cases, primarily
due to growing parental refusal of the measles-mumps-rubella (MMR) vaccine.
And these diseases are not just minor annoyances--they can be serious,
debilitating, even deadly.
The MMR vaccine may never be proven totally
safe. But we will never be safe from these diseases without it. Parents
should at least be told that.
HOWARD FIENBERG
Statistical Assessment Service
Washington