Microbiologist Janet Cahill, in collaboration with the antibiotic stewardship team, championed a diagnostic change that improved patient care. Her project implemented a new use of polymerase chain reaction (PCR) testing for influenza (the flu). Cahill worked with the information technology (IT) team to ensure the PCR tests would interface properly and the information would flow to the prescribers and pharmacy. Although the earlier type of test had a sensitivity of 85% in detecting influenza type A and 59% for influenza type B, the new PCR test was much better, being 100% sensitive for both flu types. This allowed the hospital to avoid giving oseltamivir, a drug commonly used to treat the flu, to flu-negative patients, who would not benefit. The proportion of patients who did not have the flu but did receive oseltamivir improved, falling from 19.1% during the flu season before the project to 1.9% the flu season after. The mean length of hospital stay for patients who received at least one dose of the drug fell from 6.39 days to 3.95 days. Although the PCR test is costlier than the older test, its use prevented a significant amount of unneeded drug from reaching patients and shortened lengths of stay. Cahill also championed use of another PCR test that identifies patients' blood pathogens in 1 hour, down from 27-37 hours. Cahill's efforts helped in pursuing the goal of reducing the use of inappropriate or unnecessary antibiotics.