Calling the Shot
Can an effective inoculation be developed to halt the spread
of genital herpes? An IUSM clinical trial seeks that answer.
It’s an unwelcome gift that keeps on giving … from
the forty-five million or so Americans who have it to their unprotected
sexual partners. Genital herpes affects one in five Americans age
twelve and older, according to the Centers for Disease Control,
yet most of those who carry it are unaware of their infection. Since
the late 1970s, the incidence of this form of the herpes virus has
mushroomed thirty percent in the U.S.
Because there is no known cure for genital herpes, researchers are
focused on preventing it. A genital herpes vaccine is being evaluated
at the School and at nineteen other medical centers nationwide in
hope of developing a defense against the highly infectious disease.
This Phase III trial is geared exclusively to women because an
earlier, similar study showed more positive results in reducing
the infection in women than men. If found to be effective, the trial
vaccine could be given to females prophylactically, before they
become sexually active.
The trial under way at IUSM is enrolling women between the ages
of eighteen and thirty who are not infected with herpes simplex
1, the oral variety that causes fever blisters or sores, or herpes
simplex 2, the source of genital herpes. Each participant is randomly
assigned to receive either the herpes vaccine or a hepatitis A vaccine
which already has been approved by the Food and Drug Administration.
Trial volunteers receive three doses of one of the vaccines within
a six-month period, followed by several months of periodic clinic
visits and consultations with trial coordinators.
“The vaccine is not a cure for those already infected with
genital herpes, but it could have a huge effect on protecting women
and their partners from this highly infectious disease,” notes
Kenneth Fife, MD, PhD, professor of medicine and the study’s
principal investigator. “This trial is exclusively for women
who do not have either form of herpes, and this makes the screening
process more difficult since many are exposed to herpes through
cold sores at an early age.”
Some people infected with genital herpes experience no symptoms
at all. In others the disease may cause a range of discomforts,
from flu-like symptoms to recurrent painful sores in the genital
or groin areas. And although genital herpes isn’t fatal to
adults, it can cause potentially fatal infections in infants if
the mother is shedding the virus at the time of delivery.
Certain antiviral medications can prevent or shorten outbreaks
of genital herpes. Latex condoms can help defend against the infection
but do not provide guaranteed protection; the only known preventive
measure is abstinence.
The clinical trial is sponsored by the National Institutes of Health
and GlaxoSmithKline. More details can be found at http://medicine.iupui.edu/ctp/trials/genital%20herpesprev.html.
Parental Consent
If vaccines were available to prevent sexually transmitted diseases,
many parents would have their children inoculated. That is an initial
finding in a study conducted by IU School of Medicine and IU School
of Nursing researchers.
“We found very high levels of acceptance by parents in this
study,” says Gregory D. Zimet, PhD, professor of pediatrics
in the Section of Adolescent Medicine. “At least ninety percent
of the parents we surveyed expressed a favorable reaction to vaccinating
their children against sexually transmitted diseases.”
Preliminary interview results from the study were published in
the journal Social Science and Medicine. Lead author is Rose M.
May, PhD, RN, of the IU School of Nursing. Dr. Zimet and Lynne Sturm,
PhD, a member of the Riley Child Development Center, were co-authors
of the study.
The study surveyed 300 parents with children between the ages of
twelve and seventeen. The parents filled out computerized questionnaires
designed to assess their attitudes about potential STD vaccines
for genital herpes, gonorrhea and HIV-AIDS. The confidential survey
also asked them to rate the acceptability of a series of vaccine
scenarios in which some vaccines were described as preventing a
sexually transmitted infection and others were described as targeting
viruses not transmitted through sexual contact.
“It is important to note that this was a select group of
parents who were accompanying their adolescent children to medical
appointments,” Dr. Zimet emphasizes. “It is possible
that acceptance of STD vaccinations would not be as high in a more
representative sample of parents.”
One of the main predictors of non-acceptance, notes Dr. Zimet, was
concern that an STD inoculation might lead an adolescent to engage
in sexual activity or to be less vigilant about condom use. He adds
that parents who oppose routine vaccinations in general also are
likely to oppose STD vaccination.
Dr. Zimet and his colleagues note that there is concern among some
parents that an STD inoculation might lead to increased sexual activity
among adolescents.
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