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Tests on two vaccines offer hope on herpes

More than a decade has passed since the public's fear of herpes subsided in the face of AIDS, a greater threat. But quietly, scientists across the country are testing experimental vaccines they hope will curb what remains the most widespread sexually transmitted disease.

Buoyed by signs that one of the vaccines spurs the body to produce disease-fighting antibodies, the Johns Hopkins School of Medicine is among two dozen institutions that are recruiting more than 2,000 adult volunteers considered in danger of catching herpes.

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Given herpes' prevalence -- an estimated 40 million Americans are infected -- it doesn't take much to be considered at risk. Researchers are looking for healthy adults with multiple sexual partners and monogamous adults whose partners have herpes.

"Very few people die of this disease," said Dr. Jonathan Zenilman, an infectious-disease specialist who is co-directing Hopkins' part of the study.

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"But there's a lot of anxiety and collateral damage that occurs because of this disease. People are really distraught by it."

The disease can kill babies and people with ravaged immune systems, but its damage is ordinarily limited to periodic outbreaks of genital sores.

In another arm of the herpes fight, scientists at the National Institutes of Health and the University of Washington in Seattle are testing a similar vaccine on 200 adults who are already infected in hopes that it will reduce the frequency and severity of outbreaks.

The next two years should demonstrate whether vaccine researchers are on the right track. If successful, the protective vaccine tested at Hopkins and elsewhere would probably be offered on a voluntary basis to sexually active adults, say scientists associated with the study.

"Herpes has been around forever," said Dr. Anne Rompalo, who is overseeing the study at Hopkins. She cited references in Greek and Roman literature to genital sores that sound suspiciously like the herpes rash, and to poetic asides in Shakespeare.

It was the sexual revolution of the 1960s and 1970s that fueled the spread of herpes and placed it squarely in the public's consciousness.

Although the disease has remained prevalent, the advent of a universally fatal disease -- acquired immune deficiency syndrome quieted public discussion of herpes.

Herpes is a viral disease that produces outbreaks of sores on the male and female genitals and on other mucosal tissues such as the mouth. Once acquired, the virus burrows into the sensory nerve cells alongside the spinal cord, flaring periodically to produce a rash that can last 21 days.

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No cure for disease

The only existing treatment is the drug acyclovir, which makethe sores heal faster and lengthens the period of time between outbreaks. But the disease cannot be cured, although some people experience fewer outbreaks as the years progress.

With AIDS still killing people at a steady pace without a cure or vaccine in sight, why the attention on a relatively benign disease that rarely kills or cripples?

"Suppose you are in a monogamous relationship with someone and you are the one infected," said Dr. Rompalo, who runs the city's sexually transmitted disease clinic in East Baltimore. "Wouldn't it be nice to have a vaccine to protect your partner?"

Herpes sufferers frequently say their greatest anxiety comes from the possibility of giving partners an affliction that never goes away. The infection also prompts some people to withdraw socially, fearing having to broach the topic with anyone.

There are other reasons to find a vaccine, researchers say.

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First, the disease is extremely difficult to prevent. Studies have smashed the conventional wisdom that infected people can avoid transmitting herpes by abstaining from sex during

outbreaks. It turns out that infected people can spread it between outbreaks, just when they think they are "safe."

"Half of the people who have herpes got it from partners who were not having an outbreak at the time," Dr. Zenilman said.

Another complication is that many infected people never gesymptoms. They, too, can transmit the disease, but they have no inkling that they should even warn partners that they are at risk.

Also, a woman having an outbreak around the time of childbirth can transmit the virus to her newborn infant -- sometimes with fatal consequences. Doctors frequently perform Caesarean sections on women who are having outbreaks, which keeps the baby from rubbing against infectious lesions while passing through the birth canal.

But a woman having her first outbreak during the third trimester of pregnancy can transmit the virus through the placenta. In such cases, a surgical delivery would not necessarily be protective.

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The number of infected infants is small. Perhaps a half-dozen infected babies are born each year at Hopkins. Nationally, about one in 1,000 newborns is infected, and many who catch the virus avoid serious complications with treatment. But the disease is sometimes fatal and can cause brain-damaging complications such as encephalitis in babies who survive.

"Most people with herpes have a baby who is normal," Dr. Zenilman said. "But when transmission does happen, it can be devastating."

Finally, doctors believe that herpes facilitates the transmission of the human immunodeficiency virus, which causes AIDS. This is because herpes sores seem to provide a portal of entry for HIV, a ready route to the bloodstream.

At Hopkins, physicians are trying to recruit 200 of the 2000 volunteers needed for a trial of the "protective vaccine" -- one that would prevent uninfected people from ever catching herpes. Volunteers will receive an initial injection and two boosters of vaccine or a placebo, and will be followed for 18 months.

Recruitment hasn't been easy, despite payments of $600 to volunteers who complete the study.

"It's not an easy disease for people to come forward with," Dr. Zenilman said.

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Smaller studies have shown that the vaccine is safe, producing only swelling at the injection site and minor symptoms such as low-grade fever. The vaccine caused the immune system to produce antibodies against the the herpes virus, but that doesn't mean it will truly protect people in danger of contracting herpes.

Results are modest

Preliminary tests on the "therapeutic" vaccine for people who already have herpes has produced modest results. In a test of 98 people, vaccinated volunteers had one-third fewer outbreaks than did those receiving a placebo. If the vaccines work, they would become the first successful ones for a chronic viral disease.

The experimental vaccines are produced through a joint venture of Chiron, a biotechnology company in Emeryville, Calif., and Ciba-Geigy, a large Swiss pharmaceutical company. The vaccines contain proteins that appear on the coating of the herpes virus and are not capable of transmitting disease.

Mark Wasserman, a 50-year-old federal economist who was diagnosed with herpes 15 years ago, said he is rooting for a vaccine even though he believes people can overcome the social stigma of herpes, forge new relationships and get married, as he did. For 10 years, he has run a herpes support group in Washington, D.C.

"If the studies produce a vaccine that prevents infection, the whole social stigma of herpes would be eliminated," he said.

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HOW TO VOLUNTEER

Those interested in volunteering for herpes vaccine trials may call:

* The Johns Hopkins School of Medicine: 550-2607.

* National Institute of Allergies and Infectious Disease, Bethesda: (301) 496-1836.

Support groups

* Baltimore HELP -- 792-8788.

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* Washington HELP -- (301) 369-1323.

* National Herpes Hotline -- (919) 361-8488 (information about other herpes support groups and about herpes in general).


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