PLANT VERMICIDES OF HAITIAN VODOU SHOW IN VITRO ACTIVITY AGAINST

Haitian Vodou priests (houngans) and priestesses (mambos) use plant remedies to treat many illnesses, including intestinal parasite infections. The present study screened 12 plants used in Vodou treatments for intestinal parasites to detect in vitro activity against infective-stage larvae of the hookworm Ancylostoma caninum. Water-soluble extracts of 4 of the 12 plants inhibited serum-stimulated feeding by larval A. caninum in a dose-dependent manner. All 4 plant extracts inhibited feeding induced by the muscarinic agonist arecoline, suggesting that these plant extracts may inhibit the insulin-like signaling pathway involved in the recovery and resumption of development of arrested A. caninum larvae. These results indicate that at least some of the plants used in traditional Haitian medicine as vermifuges show activity against nematode physiological processes. Hookworms infect -1.3 billion people worldwide, mostly in areas of rural poverty such as those found in Haiti (Stoll, 1947; Pawlowski et al., 1991; Chan et al., 1994; Crompton, 1999, 2000). They attach to the human intestine and feed on blood, leading to cumulative hemoglobin losses that impair immunity, cause iron-deficiency anemia, and result in morbidity for ~130 million and death for ~65,000 people annually (Crompton, 2000; Muller, 2001). In mothers, hookworm infections contrib- ute to premature and low-birth- weight newborns; in children, these infections can delay physical and cognitive growth (An- derson, 1992). Among individuals and families infected with hookworms and other pathogens in Haiti, reduced productivity contributes to a cycle of poverty that makes health care and the rudiments of hygiene unaffordable or unsustainable for most of the population (Farmer, 1995). Ancylostoma duodenale and Necator americanus are the ma- jor hookworm species that infect humans. Adult females of both species release thin-shelled, oval eggs in the lumen of the hu- man gut (Muller, 2001). After being shed and over the course of several days, the eggs hatch, and the larvae undergo 2 molts to the infective third-stage larva (L3). The L3 is developmen- tally arrested and nonfeeding; instead, it relies on nutrients stored in its tissues for survival (Anderson, 1992). The long- lived infective L3 survive adverse environmental conditions