Cynthia L. Chappell is although retired from teaching, Cynthia L. Chappell is an active investigator in the Center for Infectious Diseases at the University of Texas School of Public Health. Cynthia L. Chappell have had a longtime interest in human parasitic diseases and have published a large number (~100) of peer-reviewed research papers, textbook chapters, and technical reports on these subjects. Cynthia L. Chappell's research has included several human parasites, but has focused primarily on Cryptosporidium. Cynthia L. Chappell have received multiple grants from the NIH and EPA to support my research. Of special note, the Cryptosporidium Volunteer Studies, carried out for 13 years, were the first and only such studies for this parasite and have provided important information on the natural history of the infection and the host immune response to the parasite.