Defense Lab Tests New Vaccine for Old Menace
By Douglas J. Gillert
American Forces Press Service
WASHINGTON, Dec. 2, 1999 Army Spc. Winnona Vanson frowned as she looked at the circular, reddish bump on her upper left arm.
"It itched a lot," she recalled, "but the worst part was changing the bandage."
Vanson is one of about 150 volunteers who have participated in two clinical trials for a new smallpox vaccine at the U.S. Army Medical Research Institute for Infectious Diseases, Fort Detrick, Md. Because she's also on the staff there, she had to be inoculated against all sorts of diseases, including smallpox. She said she felt she might as well volunteer for the clinical trial.
For awhile after she was vaccinated with the investigational new drug, her lymph nodes swelled and her arm hurt so much she couldn't lift it, she said. But the swelling, soreness and itching were the only side effects she experienced.
Vanson doesn't know if she was inoculated with the new drug being developed or the old smallpox vaccine, available in limited quantities because it is no longer manufactured. Nor does the physician conducting the trial know which volunteers got which vaccine. That information won't be made known until early 2000.
"Our objective was to first put the product to human use to see if it's safe," said Army Dr. (Maj.) Trinka Coster, chief of the clinical studies department and director of the smallpox clinical trials. "We then will look to see if the vaccine does what it's intended to do, protect against smallpox."
Coster said a new vaccine is needed because humans have become more susceptible to smallpox since it was mostly eradicated in the 1970s and vaccinations were stopped. The services ended smallpox vaccinations in the early 1980s, she said, except for those who are most likely to be exposed to the virus -- special operations troops and laboratory workers, for example.
With a mortality rate of 30 percent, smallpox has killed 300 million people worldwide in this century alone. Although the only two known living smallpox virus specimens are kept in guarded laboratories in the United States and Russia, microbiologists like Vicki Pierson of the Joint Vaccine Acquisition Office, adjacent to the Fort Detrick lab, fear the virus may exist in labs unknown to authorities.
Smallpox is a lethal weapon in the wrong hands because it's highly contagious and easily dispersed in the air, said Pierson, product manager for the new vaccine. Unknowing victims will spread the virus for days before the incubating disease erupts with symptoms, she said.
The Fort Detrick lab began developing a new vaccine in the early 1990s, using modern technology to produce a better product.
"The method of production for the current licensed product was basically unchanged from the way it was produced in 1792," Pierson said. "We now have an opportunity to use more modern technology to make a cleaner, safer product."
In the centuries-old production method, smallpox cultures were grown on the bellies of calves, then scraped off. As a result, the vaccine contained significant amounts of bacteria, Pierson said. Now, it's possible to grow smallpox on mammalian tissue cultures in a sterile laboratory.
If the Fort Detrick clinical trials prove the new drug to be safe for humans, Pierson's office will begin testing the drug on several thousand volunteers. She said those tests should begin by the end of 2001, and a new smallpox vaccination could be licensed by 2003. Because manufacturing capability is part of the developmental process, the vaccine would be available soon after it's licensed.