Studies on Schistosomiasis

Abstract
Summary During the second year of screening potential protective ointments against schistosomiasis using white mice and cercariae of Schistosoma mansoni, 127 compounds were tested with the following results: Ten ointments gave complete protection following the “four hour immersion test.” These were: Actamer (10%) in Silicote; Actamer (5%), Hexachlorophene (3%) and benzyl benzoate (20%) in wool fat; benzyl benzoate (20%) and Abbott's Covicone with repellents (E-4856); Hexachlorophene (10%) in wool fat; Hexachlorophene (5%) in wool fat; Hexachlorophene (5%), benzyl benzoate (20%), copper stearate and copper oleate in ether; Hexachlorophene (5%), copper stearate (40%), with copper oleate (40%) in ether; Hexathlorophene (3%) and Abbott's Covicone with repellents (E-4856); Hexachlorophene (10%) and olive oil (10%) in petrolatum; and Hexachlorophene (3%) in Pro-derna. Eight more gave over 99 PRP with the four hour immersion test; fifteen provided 90 to 98.9 PRP while 94 gave less than 90. The four hour immersion test with cercariae of S. japonicum gave equivocal results due to the small number of cercariae available. Of the 10 ointments providing complete protection following the four hour immersion test mentioned above, the following were selected as most nearly fulfilling the prerequisites of an ideal protective ointment: Actamer (10%) and Silicote; Actamer (5%), Hexachlorophene (3%) and benzyl benzoate (20%) in wool fat; benzyl benzoate (20%) and Covicone with repellents; Hexachlorophene (5%) and wool fat; and Hexachlorophene (3%) and Pro-derna. These should be checked first for toxicity to man and then tested against other human schistosomes using experimental animals.