Protozoan infections are caused by tiny, single-celled organisms called protozoa. These microorganisms can enter the human body through contaminated food, water, or insect bites. Common types of protozoan infections include malaria, caused by the Plasmodium parasite, and giardiasis, which is caused by Giardia lamblia. Symptoms can vary widely, ranging from mild digestive issues to severe fever and fatigue. Preventing protozoan infections often involves practicing good hygiene, such as washing hands and drinking clean water. In some cases, medications can help treat these infections effectively. Awareness and education about protozoan diseases are essential for reducing their impact on public health.