Many organisms are parasitic—viruses, bacteria, and eukaryotic organisms. However, parasitology typically covers only eukaryotic parasitic organisms, both single-celled and multicellular. This course will cover protozoa (also known as Protista), which are just one group of eukaryotic parasites and will focus on those that live in just one area in our body: the intestinal tract.
People in the United States don't usually consider parasitic diseases major infectious diseases. However, parasites are ubiquitous and often depend on sanitation, public health norms, climate, and the individual's ability to fight them off. As climate changes and more people become more immunosuppressed, parasitic diseases become important.
Although we are focusing here on intestinal protozoa, parasites can inhabit many areas of our body and belong to many groups of organisms. The diagram to the right illustrates just some of our many parasites!
