[1] Univ Calif San Francisco, Div Gastroenterol, San Francisco, CA 94143 USA
[2] Harvard Univ, Sch Publ Hlth, Boston, MA 02115 USA
[3] Northwestern Univ, Sch Med, Chicago, IL USA
[4] NIAID, NIH, AIDS Clin Trials Grp, Bethesda, MD USA
[5] Gilead Sci Inc, Foster City, CA USA
[6] Beth Israel Med Ctr, New York, NY 10003 USA
[7] Albert Einstein Coll Med, New York, NY USA
[8] Birmingham Vet Affairs Med Ctr, Birmingham, AL USA
[9] Univ Alabama, Birmingham Sch Med, Birmingham, AL USA
[10] Univ Calif Davis, Med Ctr, Sacramento, CA 95817 USA
[11] Univ Cincinnati, Coll Med, Cincinnati, OH USA
[12] Univ Nebraska, Ctr Med, Omaha, NE 68198 USA
[13] St Lukes Roosevelt Hosp, Div Infect Dis, New York, NY USA
[14] Columbia Univ, Coll Phys & Surg, New York, NY USA