[1] Columbia Univ, Sch Nursing, 617 West 168th St, New York, NY 10032 USA
[2] Columbia Univ, Mailman Sch Publ Hlth, New York, NY USA
[3] Columbia Univ, Coll Phys & Surg, Div Infect Dis, New York, NY USA
[4] Publ Hlth Solut, Res & Evaluat Div, New York, NY USA