The CIA examined allegations that an outbreak of West Nile fever in New York might have been an act of terrorism ordered by Iraqi President Saddam Hussein but concluded that there was no evidence of a biological attack, CIA officials said yesterday.

"We have looked into that, and there's nothing that we've found that would support the notion at all," a senior agency official said.

The outbreak of the virus has killed five people and made at least 27 others sick. West Nile fever is spread by mosquitoes from birds to humans, causing flu-like symptoms. Senior CIA officials said the agency's review of press reports did not constitute a formal investigation by intelligence officers or analysts. "To imply that there is an investigation gives it more credibility than it deserves," said another official, adding: "We don't have any intelligence to substantiate" a biological attack.

The New Yorker cited an account by Mikhael Ramadan, an Iraqi defector who says Saddam Hussein told him in 1997 that the Iraqi regime was planning to weaponize West Nile virus. Ramadan's account, excerpted from his new book, "In the Shadow of Saddam," first appeared in April in the London Daily Mail. Ramadan claims to have worked as Saddam's double for 20 years.

New York City health officials and the Centers for Disease Control in Atlanta also said yesterday they had no evidence that the fever outbreak was anything but a natural occurrence. Officials are trying to determine whether the virus was brought to the United States by a smuggled bird, an infected person or even by a mosquito inside a plane.