Abstract

Schistosomiasis is a widespread parasitic infection whose intermediate host is aquatic snails and affects more than 250 million people worldwide. Although control of the snails with synthetic molluscicides is possible, it is not greatly preferred due to concerns of environmental toxicity and the relatively high cost of the chemicals. Conversely, organic plant-derived molluscicides are a better alternative that can be used to reduce the incidence of the disease. The objective of this study was to evaluate the molluscicidal activity of the plants Phytolacca octandra, P. dodecandra and Balanites aegypiaca. The major parts of the whole plant (berries, leaves, stems and roots) were collected, air dried to constant weight, macerated to a fine powder and extracted separately using methanol in soxhlet apparatus.  The extracts were screened for activity using brine shrimp lethality test and thereafter tested for molluscicidal activity. There was no significant difference observed in the activity of the plant parts studied and of the three plant species in the brine shrimp lethality test. Similarly, no significant difference in molluscicidal activity of the plant parts studied and in the three plants against bulinus snails was detected. It was concluded that that the three plants can be used in the control of schistosomiasis transmitting snails.

Key words: Schistosomiasis, molluscicidal, Bulinus snails, brine shrimp, Phytolacca octandra, Phytolacca dodecandra, Balanites aegypiaca