[1] Univ Calif Davis, Div Rheumatol Allergy & Clin Immunol, Dept Internal Med, Davis, CA 95616 USA
[2] Univ Calif Davis, MIND Inst, Davis, CA 95616 USA
[3] Univ Calif Davis, Dept Pediat, Davis, CA 95616 USA
[4] Univ Calif Davis, Dept Med Microbiol & Immunol, Davis, CA 95616 USA
[5] Kaiser Permanente Northern Calif, Div Res, Oakland, CA USA
[6] Calif Dept Publ Hlth, Environm Hlth Invest Branch, Richmond, CA USA
[7] Johns Hopkins Univ, Sch Med, Dept Pediat, Stanley Div Dev Neurovirol, Baltimore, MD 21205 USA