Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Oocysts
Introduction
An oocyst is the spore phase of certain protists, such as Cryptosporidium and Toxoplasma. This state can survive for lengthy periods outside a host and is very resistant.
A thick-walled structure in which sporozoan zygotes develop and that serves to transfer them to new hosts like in mosquitoes (Anopheles gambiae).