[1] Ctr Dis Control & Prevent, Influenza Div, 1600 Clifton Rd NE,H24-7, Atlanta, GA 30329 USA
[2] Texas A&M Univ, Coll Med, Baylor Scott & White Hlth, Temple, TX 76508 USA
[3] Baystate Med Ctr, Dept Med, Springfield, MA 01199 USA
[4] Beth Israel Deaconess Med Ctr, Dept Emergency Med, Boston, MA 02215 USA
[5] Cleveland Clin, Dept Med, Cleveland, OH 44106 USA
[6] Hennepin Cty Med Ctr, Dept Emergency Med, Minneapolis, MN 55415 USA
[7] Hennepin Cty Med Ctr, Dept Med, Minneapolis, MN 55415 USA
[8] Intermt Med Ctr, Dept Med, Murray, UT USA
[9] Univ Utah, Salt Lake City, UT USA
[10] Johns Hopkins Univ, Sch Med, Dept Med, Baltimore, MD 21205 USA
[11] Montefiore Med Ctr, Albert Einstein Coll Med, Dept Med, Bronx, NY 10467 USA
[12] Ohio State Univ, Dept Med, Columbus, OH 43210 USA
[13] Univ Colorado, Sch Med, Dept Emergency Med, Aurora, CO USA
[14] Univ Iowa, Dept Emergency Med, Iowa City, IA 52242 USA
[15] Univ Miami, Dept Med, Miami, FL USA
[16] Univ Michigan, Sch Publ Hlth, Ann Arbor, MI 48109 USA
[17] Vanderbilt Univ, Med Ctr, Dept Med, Nashville, TN USA
[18] Vanderbilt Univ, Med Ctr, Dept Hlth Policy, Nashville, TN USA
[19] Wake Forest Sch Med, Dept Med, Winston Salem, NC 27101 USA
[20] Washington Univ, Dept Med, St Louis, MO 63110 USA
[21] Vanderbilt Univ, Med Ctr, Dept Pediat, Nashville, TN 37232 USA
[22] Univ Michigan, Dept Internal Med, Ann Arbor, MI 48109 USA
[23] Univ Michigan, Dept Microbiol & Immunol, Ann Arbor, MI 48109 USA
[24] Vanderbilt Univ, Med Ctr, Dept Biostat, Nashville, TN USA
[25] Vanderbilt Univ, Med Ctr, Vanderbilt Inst Clin & Translat Res, Nashville, TN USA
[26] Vanderbilt Univ, Med Ctr, Dept Emergency Med, Nashville, TN USA