The effect of zinc supplementation on parasitic reinfestation of Guatemalan schoolchildren.

One hundred thirty children (65-95 mo old) from a low-socioeconomic neighborhood of Guatemala City participated in a randomized, double-blind, controlled trial of zinc supplementation. One group received 10 mg Zn/d (n = 65) and the other group received a placebo (n = 65); 90 +/- 9.2 doses were given over 120-150 d.