Abstract
The intestinal protozoan parasite, Cryptosporidium, is a leading cause of diarrhea-associated illness and death in young children, immunocompromised individuals, and neonatal ruminant animals. This apicomplexan parasite completes its entire lifecycle within a single host, involving a timely and coordinated progression through asexual and sexual developmental stages. With no fully effective drugs or vaccines available, a deeper understanding of the parasite's lifecycle stages is crucial for identifying new molecular targets for disease intervention. In this review, we discuss recent advances in understanding the Cryptosporidium developmental lifecycle, stage-specific gene expression, and the role of parasite proteins in invasion, asexual proliferation, and sexual stages. We also discuss the lifecycle stages targeted by a few highly effective anticryptosporidial compounds.