Study design, setting, and participants
A prospective study from birth was done in the District of Quininde in Esmeraldas Province, Ecuador, as described.17 The District serves a population of approximately 150,000 with limited access to basic services. The economy in the District is based largely on agricultural activities. Neonates were recruited at a public hospital in the District between November 2005 and December 2009. Follow-up evaluations and sample collections were done at 13 months and 2, 3, 5, and 8 years of age.