N.Y. Outbreak Not Work of Terrorists, Experts Say

An outbreak of West Nile-like virus that killed five people and made 50 ill in New York last month was very unlikely to have been a botched bioterrorist attack, experts said Monday.

They said the virus would be an extremely poor choice for a biological weapon, and might have gone unnoticed had the attack been anywhere but New York.

This week’s New Yorker magazine said the CIA was worried about the outbreak and was investigating the possibility that bioterrorism was involved.

But the CIA said there was no evidence to suggest the virus had been deliberately planted. “We have seen the press reports but we have no intelligence to substantiate that claim,” a CIA official said.

The New Yorker report cited a book written by an alleged Iraqi defector using the name Mikhael Ramadan, who said he had been told by Iraqi leader Saddam Hussein that Iraqi scientists were modifying West Nile-like virus for use in a weapon.

The Centers for Disease Control and Prevention said there was no evidence the outbreak--which is spread by mosquitoes from birds to people--was the result of anything but natural events.

“We don’t see anything that indicates that it’s anything but Mother Nature at work,” CDC spokeswoman Barbara Reynolds said in a telephone interview.

“We are going to look at all possibilities. But we have to say frankly at this point we don’t see anything here.”

Reynolds praised New York’s health authorities for their quick response to the outbreak. The virus was at first identified as St. Louis encephalitis virus, a closely related virus that causes brain inflammation and, sometimes, death.

Spraying with insecticides was started almost immediately and people were warned to use insect repellent and cover up to avoid bites from the mosquitoes that carry it.

“In other parts of the country it may never have been picked up as an outbreak. But because New York has such an excellent disease surveillance system, they were able to quickly pick up on what was going on,” Reynolds said.

West Nile virus is common in parts of Africa and Asia and was recently seen in Romania, but it had never been reported in the Americas.

The CDC is checking to see whether the virus was carried in by a smuggled bird, an infected person or even by a mosquito that found its way into a plane before a flight to the United States, but Reynolds said the carrier might never be known.

“We live in a global village at this point, and emerging infectious diseases are something we are all going to have to deal with more and more,” she said.

Dr. Donald Henderson, head of the Johns Hopkins Center for Civilian Biodefense Studies in Baltimore, said it is possible West Nile-like virus has been present in the Americas, but was mixed up with St. Louis encephalitis because the two look so much alike. “They might have missed it before,” he said.

Michael Osterholm, an expert in bioterrorism, said he also doubted the New York outbreak was caused deliberately.

“I am the one who has been saying from the get-go that I am extremely concerned about bioterrorism,” he said in a telephone interview. “But I find myself saying this is not it.”

West Nile-like virus can kill--about 4% to 8% of victims, usually the weak or elderly, can die from it. But it has never been named as a likely bioterrorism agent.

“It seems to be, from a terrorism standpoint, . . . far from effective,” Osterholm said. “Part of what a terrorist wants to do is create terror and an outbreak like this virus possibly could go missed in many different communities,” he added.

“If this is what a terrorist would do,” Osterholm said, “ . . . I think we have a fairly bright future.”