Experts question US germ detection rollout
Date: 24-Jan-03
Country: USA
Author: Maggie Fox, Health and Science Correspondent
Many of the Environmental Protection Agency's 3,000 air quality monitoring stations, now sampling for pollution, would be updated to also check for bacteria or viruses, the White House said.
"It's part of our precautions to protect the country from any potential threats of bio-weaponry," White House spokesman Ari Fleischer said. "We have no specific information about any such threat, but it's part of the whole precautions the country has been going through since Sept. 11," he added.
"The EPA is moving forward with the program beginning today," Fleischer said. He said the system will be deployed in major population centers across the country, and the CDC will monitor equipment on a regular basis. It will be funded by the new Department of Homeland Security.
The EPA had no immediate comment, but experts on biological attacks questioned how well such a system would work.
"I cannot imagine it would be of any useful purpose in a bioterrorism attack," said Tara O'Toole, who heads the Center for Civilian Biodefense Strategies at Johns Hopkins University in Baltimore.
CRYING WOLF
"The problem is that all of the technologies we now have have a very high false positive rate. They go off when there is not a biological attack," she added in a telephone interview.
The government has been investigating the idea of germ detectors for years, and routinely uses chemical detectors. For instance, they were used outside last year's Super Bowl National Football League championship in New Orleans.
But there is a big difference between detecting a chemical in the air and detecting bacteria or viruses.
The air is already full of both and finding dangerous ones requires either a genetic test using a DNA sample, or a test using antibodies that stick to and mark a specific microbe.
Dozens of germs are considered likely warfare or terrorism agents, so tests would have to be specific to each. Agents include the bugs that cause anthrax, botulism, plague, smallpox, tularemia, Ebola and several other hemorrhagic fevers, brucellosis, glanders and psittacosis.
The EPA devices would use filters that would be removed regularly and checked at CDC labs, which O'Toole said would be time-consuming and costly.
"The labs that would do this testing are public health laboratories," she said. "That system is already severely underresourced and overstretched."
And the detectors can only sample a limited amount of air in a very small surrounding area.
"You have got to have them in the right place at the right time," noted one Army expert who asked not to be named.
Bioterrorism experts have outlined many different scenarios involving a germ agent. One involves spraying it over a city such as Washington or New York, where detectors might pick up the microbes.
But others include contaminating the air filter system in a large shopping mall or disseminating germs in a mass transit station or train.
