W. Nile Virus’ Spread Feared

ATLANTA --West Nile virus, the mosquito-borne illness that has killed at least 18 people in the United States since 1999, has established itself in the eastern half of the country and threatens to spread to other parts of the Americas, U.S. health experts said Thursday.

A report by the U.S. Centers for Disease Control and Prevention said the virus, which can cause deadly brain inflammation in humans, birds and horses, was detected in 359 counties in 27 U.S. states and the District of Columbia last year, including 16 states previously free of the disease.

Nine Americans died in 2001 after contracting the virus and 57 others were infected, according to the CDC

Officials with the CDC have been tracking West Nile since it struck the New York City area three years ago, killing seven people and infecting dozens of others.

They said they expected the virus to continue expanding into unaffected areas, largely through the migration of infected birds.

“Based on what we’ve seen in the last couple of years, there is no reason that the virus wouldn’t continue to expand its geographical range within the United States,” said Dr. Stephen Ostroff, acting deputy director for the CDC’s National Center for Infectious Disease.

Ostroff added there was nothing stopping the virus from marching into the Caribbean and Central and South America, which had ecologies he described as “conducive” to its spread.