A Shot in the Arm for Itching

By Anastasia Toufexis

A vaccine for chickenpox could be available by 1986

Measles, mumps, rubella, whooping cough, diphtheria, polio. One by one in this century the scourges of youth have fallen before the marvel of vaccines. But there has been no similar victory against the last of childhood's common infectious diseases: chickenpox, or as it is known medically, varicella. According to the U.S. Centers for Disease Control, the virus-caused illness strikes about 3 million youngsters each year, approximately as many children as there are babies born.

About 85% of all U.S. children have had a bout with the maddeningly itchy, highly contagious disease by age ten.

Relief is now in sight. Researchers at the University of Pennsylvania an nounced last week that early trials with a vaccine showed it was safe and 100% effective in warding off the disease in children. If the promising findings hold up, predicts Pediatrician Robert Weibel, who directed the study, "I do foresee this being used on all children as a routine immunization." Merck Sharp & Dohme Research Laboratories, which is producing the vaccine, hopes to have Food and Drug Administration approval in time for inoculation for the 1986-87 winter season.

Why has the vaccine been so long in coming?

Until quite recently, researchers had felt no particular urgency for immunization. The disease had long been regarded as a benign malady, and although it tends to hit adults more severely than children, most people seemed to suffer through the rash, high fever, sore throat and painful joints without ill effect. But increasingly, doctors have realized that varicella contains a variety of hidden threats. Among them: bacterial infections of the skin, pneumonia, encephalitis and the severe brain disorder known as Reye's syndrome. It can also be life-threatening to children taking immune-suppressing anticancer drugs. According to Government estimates, chickenpox-related illness leads to 100 deaths and 4,500 hospitalizations every year.

The trial of the new vaccine, reported in the New England Journal of Medi cine, involved 914 healthy youngsters ranging in age from one to 14,468 were injected with the vaccine, while the rest received a placebo. Neither the researchers nor the children's families knew which drug was given. Nine months later, 39 of the youngsters who had received dummy shots had developed chickenpox. But no vaccinated child caught the disease. A few children getting the vaccine had pain, swelling and redness at the injection site and chickenpox-like rashes, but there were no long-lasting or serious adverse effects. The experimental vaccine was developed from a strain of varicella vi rus isolated in 1974 in Japan by Dr. Michiaki Takahashi. Researchers used a live but weakened form of the virus to trigger the body's immunological system into producing antibodies against the disease. The idea, explains Weibel, is "to induce immunity without inducing clinical disease."

The importance of a successful varicella vaccine goes beyond protecting children. Even those who recover uneventfully can be painfully reminded of the disease in adulthood by shingles. The chickenpox virus is a member of the herpes family of viruses that can lie dormant along nerves for decades and be suddenly reactivated, possibly by stress or injury. Says Virologist Stanley Plotkin of the University of Penn sylvania: "Shingles causes severe, insane pain in one in 10,000 Americans a year."

Some researchers are concerned that the vaccine's altered vi rus might actually promote the development of shingles. Another great worry is cancer. Viruses are a suspected cause, and another member of the herpes family, the simplex virus, is under suspicion, says Plotkin, "though proof is far from complete." Dr. Kenneth Mclntosh, a pediatrician at the Infectious Disease Laboratory of Boston's Children's Hospital, warns that before the Merck vaccine can be put to widespread use, "more years" of research are necessary to resolve such questions. Researchers also need to know how long the immunity to chickenpox will last.

To young children, wary of getting yet another shot, the news of the vac cine may not be welcome. But Merck says not to worry. It hopes to combine the chickenpox vaccine with a triple-threat shot already on the market that protects against measles, mumps and rubella. Possible cost of the new four-in-one vaccine: $30.

--By Anastasia Toufexis. Reported by Mary Carpenter/New York

With reporting by Mary Carpenter