Traces of anthrax have been found on two mailboxes at a post office inside the Pentagon, officials revealed yesterday. The facility remained closed even though bioterrorist teams swept the area during the weekend and cleaned it of all remaining spores.
Meanwhile, the Mayo clinic in Minnesota revealed it had developed a new genetic method of testing for anthrax in patients. The test can produce results in one hour and could help in allaying fears among people who think they have been exposed to the potentially deadly spores but are not certain.
The Pentagon discovery drew instant attention because the building, on the outskirts of Washington DC, has already been at the forefront of the terrorist war as one of targets hit by hijacked aircraft on 11 September. It did not necessarily mean, however, that a new batch of anthrax had been uncovered.
The government believes the new cases that are still coming to light almost every day are from cross-contamination with anthrax spores already in circulation within the mail system. This raises hopes that no fresh and unidentified doses of anthrax are turning up in the US and that the crisis may be easing.
That appeared to be true of traces found on a videocassette sent to the offices of the New York City Mayor, Rudy Giuliani, for instance. On Sunday, the Mayor said the tape had come from the office of NBC news anchorman, Tom Brokaw, who was one of the first targets of the anthrax alert that has swept the US.
In the Pentagon case, investigators suspect the spores originated at a Washington postal facility where anthrax was found two weeks ago. The Brentwood sorting centre, the main hub for mail distributed through the city, was sealed off on 15 October after anthrax was found inside. Two workers died, apparently after coming into contact with an anthrax-laced letter sent to the Senate majority leader, Tom Daschle.
The post office in the Pentagon is located within a large shopping mall in the complex, that is open to the general public. One of the two mail boxes was rented to a naval employee. The other was not in use. "The entire Pentagon Concourse was decontaminated on Sunday," a spokesman insisted. "We are taking every precaution". Officials also confirmed that smallpox vaccinations had been administered to a small group of front-line medical workers involved in trying to contain the anthrax scare.
The decision reflected lingering nervousness that terrorists might attack US cities with smallpox. The impact of such an attack could be far more devastating than the damage so far caused by the anthrax scare.
Approximately 140 workers were thought to have received the injections for smallpox, a disease which, theoretically, was eradicated from the world two decades ago. There are fears that samples of smallpox kept for research purposes and sent to two repositories, one in the US and the other in Russia, could have fallen into terrorist hands. Washington is seeking to buy enough smallpox vaccines - about 300 million - to be able to vaccinate the entire American population in the event of an outbreak.
In Minnesota, Dr Franklin Cockerill III, a Mayo Clinic microbiologist, said scientists had "discovered a new DNA test that identifies anthrax in less than an hour instead of days". He said the test would enable local authorities to get test results for exposure more quickly and ease anxiety in patients who won't have to wait so long for their individual results.
In New York a funeral service was held for a hospital worker who died from inhalation anthrax. She was Kathy Nguyen, an employee of the Manhattan Eye, Ear and Throat Hospital, who died last Wednesday. The service drew more than 300 mourners and was conducted in four languages: English, Spanish, Chinese and Nguyen's native Vietnamese. Investigators still haven't been able to determine the source of the anthrax that killed her.
Over the past month, there have been 17 confirmed cases of anthrax in the US and four people have died.