Besides proving deadly, the 2001 anthrax incident caused considerable disruption.

This is a worrisome example of how the nation's overwrought response to a handful of anthrax incidents has the potential to do more harm than good.

To the Editor: Your Jan. 6 front-page article about what officials have learned from the autumn anthrax incidents made many excellent points.

In earlier years, the department typically responded to no more than a half-dozen anthrax incidents a year, all of them false alarms, officials said.

In the months that followed, the mail-borne anthrax incidents virtually erased her life as a working professional.

But these unconventional arms can still cause mass disruption; a few anthrax incidents, after all, virtually shut down the Congress.

Investigations into other suspected anthrax incidents continued in other parts of the country and abroad.

In recent days, as the anthrax incidents have ballooned, it has seemed all too apparent that the government itself has not had command of the facts.

"If we have evidence, we're going to reveal it," Mr. Fleischer said of any links between the anthrax incidents and terrorism.

He can't be answering questions on every new anthrax incident.