Studies on the rate of loss of human ascarids and reinfestation under tropical conditions were made by Cort and his collaborators in Panama.1 They found that when treatments were effectively dispensed at the beginning of the rainy season the ascaris burden four months later had reached and in some cases surmounted the pretreatment level.
During the course of field investigations on the epidemiology of ascariasis in southwestern Virginia,2 an opportunity was afforded for a similar study of reinfestation with ascarids after treatment under endemic conditions in the United States. For this purpose intensive studies were made of two small communities considered in the main report, Hawthorne, a small mining camp, and Ramsey, a discarded saw mill camp. In the main report attention was called to the fact that while nearly every home in these two communities was provided with some kind of a privy, that privy was seldom
OTTO GF. ASCARIS LUMBRICOIDESTREATMENT, LOSS OF WORMS AND REINFESTATION. JAMA. 1930;95(3):194-196. doi:10.1001/jama.1930.02720030024007