Contents

24 June 1994
Vol 264, Issue 5167

About The Cover

A false-colored scanning electron micrograph of Schistosoma mansoni (magnification x2500). This blood fluke penetrates the skin of humans after spending part of its life cycle in freshwater snails. Infection causes schistosomiasis, with the anemia and inflammation that result from the fluke settling in intestinal blood vessels. The special section beginning on page 1857 focuses on the biology of parasites and the impact of parasitic diseases. The section pages are identified by an icon representing the head of the tapeworm Taenia solium. [Cover micrograph: CNRI/Science Photo Library/Photo Researchers, Inc.]