WASHINGTON — Concern about bioterrorism mounted Wednesday as early tests showed that 31 staff members at the Capitol have been exposed to anthrax and that spores mailed to the publisher of supermarket tabloids in Florida and to NBC News in New York were the same strain.
And in an unprecedented move, the House of Representatives was closed to allow what Speaker Dennis Hastert called an "environmental sweep" of the chamber.
The national Centers for Disease Control and Prevention in Atlanta, which identified the Florida-New York strain, reported that the matching strains do not necessarily mean that the anthrax came from the same source and that further tests were needed.
It was also unclear, CDC officials said, whether it matched anthrax in an envelope sent to Senate Majority Leader Tom Daschle in Washington.
Atty. Gen John Ashcroft, appearing on a TV news program, said preliminary analysis showed that the anthrax sent to Daschle was "virulent, strong, very serious." Although anthrax occurs naturally in animals, law enforcement officials said the sample sent to Daschle was "professionally" manufactured.
"There has been some attempt to collect it, refine it and make it more concentrated," said Dr. Scott Lillibridge, head of the office for National Security and Bioterrorism in the Department of Health and Human Services.
He and Health Secretary Tommy Thompson agreed in testimony to a congressional subcommittee that the letter to Daschle was "a very serious attempt at anthrax poisoning."
But Thompson disputed reports that the anthrax was "weapons-grade."
Cultures taken from Daschle's sample showed that this particular strain of anthrax is treatable by "all antibiotics, penicillin all the way to ciprofloxacin," said Gen. John Parker, who heads the medical research command at Ft. Detrick, Md., where they were tested.
"It's a very sensitive strain," Parker said.
In other developments:
* Concern spread to the the midtown Manhattan offices of New York Gov. George Pataki, where small amounts of anthrax were found in a secure area used by state police. Employees tested negative for exposure, but everyone in the office will be given antibiotics, including the governor.
* President Bush asked Congress for an additional $1.5 billion to fight terrorism and prevent and respond to bioterrorism. It would be a six-fold increase over the $297 million Congress has appropriated for this year be used to produce smallpox vaccine and increase drug stockpiles.
* In Florida, preliminary tests showed that a threatening letter sent to a Planned Parenthood clinic in the town of Stuart, 30 miles north of Palm Beach, was contaminated with anthrax. But police were dubious, and it was sent to a laboratory in Miami for a more conclusive analysis.
In Washington, the House of Representatives was physically closed Wednesday night for what Library of Congress researchers said was the first time. Congressional leaders said it would remain shut for five days, along with its office buildings, to allow a comprehensive sweep of the facilities to determine if they contained any harmful substances.
The Senate ordered a sweep of its offices as well. But Senate leaders insisted on staying in session today, in part because they feared that a complete shutdown of Congress would sent the public an unnerving impression of the government in panic.
Among the 31 staff members who tested positive for anthrax exposure, three worked for Sen. Russell Feingold (D-Wis.), whose office is adjacent to Daschle's. Anthrax spores also were found in the Senate mail room, which is in still another office building.
Congressional leaders tried to calm edgy nerves by underscoring that none of the people who had tested positive for exposure actually had been infected and made ill. They emphasized that the anthrax involved was readily treatable and that everyone exposed was taking antibiotics.
Thompson and Lillibridge spoke to senators at a Government Affairs subcommittee in the Dirksen Senate Office Building before it was closed. They spoke calmly--in stark contrast to the atmosphere among groups of staffers, who spread the news that more than two dozen of their colleagues had tested positive for anthrax exposure.
The staffers asked each other whether they were taking the antibiotic Cipro.
Thompson told the senators that 1,200 bottles of the antibiotic had been sent to the Senate to threat those who were exposed. He said some 1,000 people will be tested.
The secretary said the FDA will approve two additional antibiotics--doxycycline and penicillin--for treatment of anthrax. Both, he said, are effective against the types of anthrax found so far.
"Because these drugs are available in generic form and produced by several manufacturers," Thompson said, "they will be relatively inexpensive and readily available."