NEW YORK (AP) - An assistant to NBC anchorman Tom Brokaw contracted the skin form of anthrax after opening a ``threatening'' letter to her boss that contained a suspicious powder, authorities and the network said Friday.(Read photo caption below) Officials quickly said there was no known link to either the Sept. 11 terrorist attacks or the far more serious inhaled form of anthrax that killed a supermarket tabloid editor in Florida last week. The 38-year-old NBC employee was being treated with antibiotics and is expected to recover.
The letter was postmarked Sept. 20 and opened Sept. 25, authorities said.
A federal criminal investigation was launched to find the source of the anthrax, and health officials scrambled to retest the powder to see if contained the germ. Initial tests had been negative, but authorities said the sample was so small they were reluctant to interpret the results.
The letter to NBC and a letter containing an unknown powder received Friday by The New York Times both were postmarked from St. Petersburg, Fla., said Barry Mawn, head of the FBI office in New York. The Times' letter was postmarked Oct. 5.
There was some similarity in the handwriting on both letters, Mawn said, declining to discuss the contents. Both were anonymous letters with no return address.
The case sent a chill through a city still reeling from the World Trade Center disaster. Emergency rooms reported a higher number of patients asking for anthrax tests or requesting antibiotics. News organizations across the country shored up mailroom security. And the postmaster general advised everyone to watch for suspicious letters and packages.
There have been anthrax scares from Connecticut to Nevada over the past week but no known cases except in Florida and New York.
The anthrax case - the nation's fourth in a week - was reported early Friday by the federal Centers for Disease Control and Prevention after tests were completed on a skin sample from the victim. Further tests on the envelope and its contents were under way.
``The most likely explanation is it was linked to this particular letter,'' said Dr. Steven Ostroff of the CDC. ``It makes sense.''
A few blocks away, one floor of The New York Times building was cleared after Judith Miller, a reporter who co-wrote a recent best seller on bioterrorism, opened a letter containing a powdery substance a spokeswoman said smelled like talcum powder.
In a story on the Times' Web site, Miller was quoted as saying the letter ``contained future threats against the United States.''
Executive Editor Howell Raines said initial tests indicated the powder did not pose any immediate problem. Air tests for radioactive and chemical substances were negative.
The Associated Press, located across the street from NBC, temporarily closed its mailroom. Other media organizations modified mail security procedures.
The skin and inhaled forms of anthrax are caused by the same bacterium. The only difference is whether the microscopic spores enter the skin through a cut or are inhaled into the lungs. It takes more than 8,000 spores to cause the inhalation form of anthrax. Neither form can be spread directly from person to person.
Mayor Rudolph Giuliani said ``People should not overreact to this. Much of this is being done to allay people's fears.''
Last Friday, a photo editor for The Sun supermarket tabloid in Boca Raton, Fla., died of the more serious inhaled form of anthrax. The American Media building where Bob Stevens, 63, worked was sealed off after anthrax was found on his keyboard.
Traces of anthrax were later found in the mailroom. Two other employees turned out to have anthrax in their nasal passages, but neither has developed the disease. Both are taking antibiotics, and one has returned to work.
In Florida, FBI agent Hector Pesquera said test results of 965 people who were in the building recently found no new infections. Pesquera said investigators are still trying to determine how the anthrax got into the building.
PHOTO CAPTION:
A man talks on a cellular phone as he watches the news zipper outside NBC's Studio 1A as it announces that an NBC employee has been affected by anthrax, Friday, Oct. 12, 2001, in New York. An assistant to NBC anchorman Tom Brokaw contracted the skin form of anthrax after opening an envelope containing a suspicious powder that was sent to her boss two weeks after the terrorist attacks, authorities said Friday. (AP Photo/Matt Moyer)