Three of the separate anthrax attacks in the US have been clearly linked by investigators who yesterday also offered a $1 million reward for information leading to the conviction of anyone involved in sending anthrax through the post.
Centre for Disease Control scientists working on the genetic fingerprints of the anthrax strains used in attacks in Florida and at the NBC TV offices in New York have established preliminarily that the strains are the same, while similarities in the envelopes have already tied the NBC case to the attack on the office of the Senate majority leader, Mr Tom Daschle. Further tests are being carried out to confirm the findings and to establish the strains used elsewhere.
A postal worker in New Jersey became the sixth confirmed case yesterday.
Meanwhile, the CBS TV channel confirmed that in New York a woman aide to its anchor Dan Rather has developed the cutaneous (skin) version of anthrax. She is being treated and is expected to recover fully. A secretary at the NBC station, and a small child visiting ABC, had previously been infected.
The CBS employee, who handles post, noticed swelling on her face on October 1st and was treated by her doctor with penicillin from October 4th.
On Friday, concerned at reports of attacks on media outlets, she contacted the Department of Health and was tested.
On Capitol Hill each of the Houses of Congress was taking a different view of the threat arising from the exposure of 31 staffers by the letter to Mr Daschle. Some 3,000 people have been tested. While the House closed down until Tuesday to allow the facilities to be swept, the Senate continued to sit.
"We're doing what any other building anywhere in the country should do in a similar situation", the House minority leader, Mr Richard Gephardt, said.
"We've got to resume normal life but we've got to be careful and vigilant and we've got to make sure we're not putting people in harm's way."
But in the same building, on the Senate side, Senator Richard Shelby was defending the decision to carry on. "We should set an example," he said.
Before the House closed down, however, its negotiators succeeded with a Senate team in reconciling their different versions of anti-terrorist legislation being sought by the Administration.
The legislation extends federal search, wire-tapping and detention powers.
Responding to some criticism that the Administration was also sending out mixed signals, the President's new Homeland Security chief, Mr Tom Ridge, moved to take centre stage in communicating the government's message, presiding over a joint press conference involving most of the agencies involved in the investigation and response measures.
Mr Ridge said that there have been five established cases of anthrax infection, with a sixth since confirmed yesterday.
The Attorney General, Mr John Ashcroft, announced that four prosecutions of hoaxers are already under way.
The American Medical Association and the US Surgeon General, Dr David Satcher, urged doctors to stop unnecessarily prescribing Cipro, the main antibiotic used to treat anthrax, to Americans who might be stockpiling it as a precaution.
"Cipro is not an appropriate treatment for anxiety," he said, warning against unnecessary use.
