[1] Tulane Univ, Sch Publ Hlth & Trop Med, Dept Epidemiol, New Orleans, LA USA
[2] Univ Wisconsin, Dept Med, Sch Med & Publ Hlth, Madison, WI USA
[3] Univ Wisconsin, Inst Clin & Translat Res, Madison, WI USA
[4] Univ Wisconsin, Sch Med & Publ Hlth, Madison, WI USA
[5] Univ Wisconsin Hosp & Clin, Dept Infect Dis, Madison, WI 53792 USA
[6] William S Middleton Mem Vet Affairs Hosp, Madison, WI USA