[1] COLUMBIA UNIV, COLL PHYS & SURG, SCH PUBL HLTH, DIV INFECT DIS, NEW YORK, NY 10032 USA
[2] COLUMBIA UNIV, COLL PHYS & SURG, DEPT PEDIAT, DIV INFECT DIS, NEW YORK, NY 10032 USA
[3] MT SINAI HOSP, NEW YORK, NY USA
[4] INST NUTR CENT AMERICA & PANAMA, GUATEMALA CITY, GUATEMALA