Tiny parasites are organisms that are too small to be seen with the naked eye. Fleas, mites, and amebas are all examples of tiny parasites. Fleas are wingless insects that feed on the blood of mammals and birds. Mites are arachnids that feed on the skin cells of animals and humans. Amebas are single-celled organisms that can cause diseases in humans. All three of these tiny parasites can cause discomfort and irritation to their hosts.