Affiliation: | 1. Neuroimmunology Branch, National Institute of Neurological and Communicative Disorders and Stroke, and the Laboratory of Microbial Immunity, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20014 USA;2. Division of Infectious Diseases, Department of Epidemiology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland 21218 USA |