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Infectious disease threat requires directed research thrust, biologist says
STANFORD -- Biological warfare has been around since soldiers in the Middle Ages lobbed putrefied corpses over castle walls, but the killing fields have changed remarkably in the last 10 years, Lucy Shapiro, professor of developmental biology, said on Nov. 15.
Speaking to the advisory council of Stanford's Institute for International Studies, Shapiro warned that besides the benefits of genetic engineering, the technology has made it possible for humans to make new pathogens. Biological pathogens are "easy to make, cheap to disseminate, difficult to detect, difficult to contain and very difficult to treat," she said.
Even without evil human intentions, we are engaged in a "Darwinian race" with viral and bacterial bugs, she said, which "knew about genetic engineering before we found out about it. They have been engineering their own resistance."
Shapiro illustrated the potential for biological warfare or terrorism by referring to the Japanese terrorist group that planted sarin in Tokyo subways and to Saddam Hussein's ability to obtain a sample of anthrax from a U.S. culture source.
The Japanese group did not use another sophisticated pathogen in its possession, she said, that could have killed people slowly so that they would spread the pathogen before they died. The pathogen was one for which only one antibiotic exists and in insufficient quantities to handle a major exposure, she said. Anthrax is so deadly, she added, that just a kilo "could wipe out 1 to 2 million people in a few days."
The last new antibiotic was developed in 1976, Shapiro said, because the war on infectious disease was thought to be over. Since then, she said, scientists have been "putting little widgets on existing antibiotics," which become outdated within two years as infectious agents develop resistance.
The rise in resistance of bugs to antibiotics is due in part to excessive unregulated use of them, she said. "Second of all, we use pesticides which change the ecological vectors of these organisms."
An escalating infectious disease threat is also related to explosive human population growth and the spread of poverty, increased travel and trade and the loss of enforceable borders. "We don't know how to quarantine," she said. Under current circumstances an infectious agent can be transferred within days by a person traveling from one continent to another.
A research effort must be launched on several fronts simultaneously to respond to the threat. Scientists need to understand sophisticated biosensors for an epidemiological detection capability. This involves not only research in genetics, but computer chip technology and photolithography, among others, she said.
A second front involves understanding the mechanisms that make a bacteria or virus virulent, in order to aid in the design of effective antibiotics. A third front involves developing an epidemic containment capability.
"These countermeasures are not science fiction, but they are not here," she said. "We need the kind of basic research we know how to do. It's not reinventing the wheel. It's putting the spotlight on a research area we neglected."
The U.S. Department of Defense has begun to funnel research funds to academia and to large pharmaceutical houses to start designing antibiotics again, she said. Funding has not come from the National Institutes of Health because their research dollars have been diverted over the years to AIDS, cancer, diabetes, heart disease and the like.
"In fact, the Centers for Disease Control is really hurting for funds," she said. "A defense is being launched, but this is the early days, and people should know about this."
Asked for evidence that infectious diseases have become a serious threat to human populations, Shapiro said that infections in hospitals are "growing dramatically," drug-resistant strains of tuberculosis now exist in major U.S. cities and a major whooping cough outbreak is a potential threat in many parts of the world.