Professor Geib received a B.A. from Montclair State College in 1974 (biology) and a Ph.D. from the University of Texas in 1981 (microbiology). He joined IU in 1984 and was awarded the Alvin S. Levine Professor of Microbiology & Immunology in 2002. In 1992, he became Assistant Dean and Director of the Indiana University School of Medicine-Terre Haute.
Professor Geib was awarded Outstanding Professor in Basic Science in 1990 and 1994. In 1998, he received the Indiana University Teaching Excellence Award. He has also been the recipient of the Max Planck Predoctoral Fellowship and the NIH Postdoctoral Fellowship.
Professor Geib is an active member of the National Rural Health Association. He is a past president of the Society of Sigma Xi.