[1] Univ Penn, Dept Pathol, Philadelphia, PA 19104 USA
[2] Univ Penn, Lab Med, Div Transfus Med, Philadelphia, PA 19104 USA
[3] Univ Penn, Dept Microbiol, Philadelphia, PA 19104 USA
[4] Univ Penn, Dept Bioengn, Philadelphia, PA 19104 USA
[5] Cooley Dickinson Hosp, Northampton, MA USA
[6] Hosp Univ Penn, Dept Med, Div Infect Dis, Philadelphia, PA 19104 USA
[7] Univ Penn, Ctr Clin Epidemiol & Biostat, Philadelphia, PA 19104 USA