Affiliation: | Department of Medical Microbiology and Immunology, Texas A&M University, College Station, Texas 77843-11141.; Robert Koch-Institut2. and Bundesinstitut für Gesundheitlichen Verbraucherschutz und Veterinärmedizin,3. 38843 Wernigerode, Germany; and Department of Molecular Microbiology and Immunology, Oregon Health Sciences University, Portland, Oregon 97201-30984. |