CBS News medical correspondent Elizabeth Kaledin reports that it is forcing them to rethink some basic assumptions about anthrax.
Manhattan's Eye, Ear, and Throat hospital remains sealed off tonight--the epicenter of an unsettling medical mystery that has health officials as baffled as the public is alarmed.
New York City's mayor is appealing for calm and perspective.
"We're talking about one case . . . one case," says Mayor Rudolph Giuliani.
But it's one case of inhalation anthrax, and, now, one death, that follows no obvious pattern. Dr. Anthony Fauci of the National Institutes of Health admits it's cause for concern.
"It may turn out ultimately to fit into the pattern, but it doesn't look that way right now and that is the reason we need to intensely investigate," says Fauci.
The woman who died, 61-year-old Kathy Nguyen, lived alone on this quiet street in the Bronx. She liked to shop, cook for her neighbors, and she worked nights in the hospital stock room. How she could have come into contact with enough anthrax spores to kill her is anybody's guess.
Specimens taken from the hospital and her home have all come back negative, and since she was too ill to speak before dying, detectives--both clinical and criminal--are reconstructing her every move.
New York Police Commissioner Bernard Kerik says, "Investigators are looking at every possible way she could have come into contact with anthrax--everything possible, everything possible."
The case has forced a reevaluation of what we know about anthrax.
"Certainly this is a moving target and an evolving situation," says Fauci.
Investigators are now considering the possibility that there can be cross contamination in the mail--meaning a letter containing anthrax spores could somehow leak those spores into other mail.
"Among many possibilities is the possibility that this person may have been exposed by a letter that was delivered to her. There is no proof of that," says Fauci.
It is just as possible that the anthrax was not linked to the mail at all. In fact, there is little proof of anything tonight except that anthrax has claimed another life and health officials are in uncharted waters.
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