In another rare step, the United States Centers for Disease Control and Prevention activated its emergency operations center in Atlanta, including sophisticated communications technology, to enhance its ability to coordinate information from other countries and to investigate any suspect cases in this country.
C.D.C. has used the operations center only twice before, for the mosquito-borne West Nile fever epidemic last year and the anthrax attacks in 2001. The last time it issued a global health alert was in 1993, to enhance measures to control tuberculosis. W.H.O. officials said they could not recall the last time an emergency global travel advisory was issued.