[1] Columbia Univ, Sch Nursing, New York, NY 10032 USA
[2] Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA
[3] Brigham & Womens Hosp, Div Global Hlth Equ, Boston, MA 02115 USA
[4] Harvard Univ, Dept Populat Med, Sch Med, Boston, MA USA
[5] Harvard Pilgrim Hlth Care Inst, Boston, MA USA
[6] Brigham & Womens Hosp, Div Infect Dis, Boston, MA 02115 USA