Effect of zinc supplementation on S. mansoni-infected hamsters.

Golden hamsters were used to determine whether intraperitoneal Zn supplementation can improve the outcome of infection with Schistosoma mansoni. The animals were divided into two groups; one received an initial intraperitoneal dose of Zn chloride (0.75 mg 100 g body wt.-1) followed by booster doses (0.25 mg 100 g body wt.-1) twice weekly for four weeks, the other group received no Zn supplement. After one week, when the initial and one booster doses were given, half of the animals in each group were exposed to S. mansoni cercariae for two hours using body immersion technique. After five weeks (one week after the final Zn supplement) the animals were killed, their worm burdens determined and their livers, kidneys, spleens, hearts and sera examined. There was a significant reduction in total worm counts in the Zn supplemented group (P less than 0.05). Also, Zn supplementation of infected animals protected them against the hepatomegaly which is very often associated with schistosomiasis. Spleen weight and Zn uptake were highest in the infected Zn supplemented group, indicating that this organ requires larger amounts of Zn to perform its various Zn-dependent immunological functions. The data suggest that Zn may enhance the ability of the body organs to resist some of the harmful effects of schistosomal infection.