Extended Spectrum Beta-Lactamase Producing Bacteria Infection

The goal of this observational study is to investigate how bacterial populations from the intestine and mouth of patients change during the hospitalization period and evaluate if some populations of specific bacteria increase or decrease the risk of acquiring an infection or becoming colonized by pathogenic bacteria. Participants will have the following samples collected during enrollment: stool samples (maximum 2x/week), blood draws (1x/week), oral swab (1x/week).