Pronounced shifts of mature Schistosoma mansoni to the lungs of mice occurred during and following various regimens of therapy with tartar emetic and Miracil D, in contrast to the relatively few worms found in the lungs of untreated controls. The magnitude of these lung shifts sometimes equalled or surpassed the collateral hepatic shifts induced by therapy. Unpaired worms outnumbered paired worms in the lungs, and the ratio of males to females varied. Many dead worms were recovered from the lungs of treated mice from 2 to 4 weeks after the initial dosage.
The lung shift provides an additional criterion for evaluating the antischistosome activity of chemical compounds in mice, supplementing information derived from the usual examinations at necropsy of the mesentery, portal vein, and liver.
Implications of possible analogous responses to therapy in human schistosomiasis are discussed.
With the technical assistance of Elizabeth Schumacher.