Biological attack threat real, but small

By David Ensor
CNN Washington Bureau

WASHINGTON (CNN) -- While U.S. officials say they have more evidence would-be terrorists remain in the United States and could be plotting more bombings, there is growing concern they may be trying to acquire biological weapons.

Many experts believe the United States is not fully prepared to deal with such an assault.

Experts say the most likely biological killer which terrorists might use is anthrax. Only 1 billionth of a gram -- the size of a speck of dust -- is lethal.

Agents made from anthrax first produce fever and stomach pains. A horrible death can occur within 24 to 36 hours of the onset of severe symptoms.

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"It is spread -- let's say in a biological terrorism event -- it would go by aerosol. You dry it and spread it as a spray and let it drift over a long way," said D. A. Henderson, the director of the Center for Civilian Biodefense Studies at Johns Hopkins University.

Still more terrifying, although much harder for terrorists to get their hands on, is the smallpox virus, a disease declared eradicated worldwide in 1980.

"To be able to move smallpox simply means to have a device within a writing ink pen that could very easily pass any customs officer, could easily pass through a metal detector, and you could have enough smallpox in there to start the world's worst epidemic," said Michael Osterholm, the director of the Minnesota Center for Infectious Disease.

Smallpox spreads like wildfire. It is estimated to have killed a 120 million people in the 20th century.

Had smallpox not been eradicated, according to the World Health Organization, the past 20 years would have witnessed some 350 million new victims -- roughly the combined population of the United States and Mexico -- and an estimated 40 million deaths -- a figure equal to the entire population of Spain or South Africa.

It can be difficult to tell the difference between smallpox and chickenpox in the first few days of the disease, when it is most infectious.

The only official stocks of the smallpox virus are in one laboratory in the United States and in one lab in Russia. But there may be others.

"There is a circumstantial evidence that Iraq, North Korea and Russia have undeclared stocks of smallpox," said Jonathan Tucker, author of a new book titled "Scourge: The Once and Future Threat of Smallpox."

During the Cold War, sources say the Soviet Union developed smallpox and anthrax weapons that could be lobbed into the United States on intercontinental missiles.

The Russians insist they only have biological agents for vaccine research. A defector said that is not true and that the weapons could end up in the wrong hands.

"In my opinion, it's a clear and present danger," said former Soviet weapons expert Ken Alibek.

"At this point, we're woefully short in vaccines and antibiotics," Osterholm told Reuters. "The [U.S.] public health infrastructure is but a shell of what it needs to be able to respond. And public health has continued to be overlooked in most of the kinds of funding that have occurred to date, in terms of trying to prepare us for terrorism."

Still, barring leakage from Russia, or help from, say, Iraq, Osama bin Laden and his al Qaeda network would have difficulty getting their hands on a biological weapon.

"We should improve our intelligence about what terrorists are doing in this area, but we shouldn't panic," said Tucker. "I think the threat is quite small."

The threat is small because biological agents are so hard to produce and hard to make into weapons.

By contrast, the threat of a chemical attack may be greater. But the United States is relatively well prepared against such an event.

As the sarin gas attack in the Tokyo subway showed six years ago, chemical agents can affect only a limited area.

If U.S. troops were to head into Afghanistan, though, going after bin Laden and his group, experts say the troops would need chemical protection.

According to newspaper reports, satellite pictures of terrorist training camps outside Jalalabad in Afghanistan show dead animals on test ranges, which suggests militants there may have been experimenting with various poisons.