David R. Peaper, MD,PhD


Laboratory Medicine


David R. Peaper, MD, PhD, director of Yale New Haven Hospital’s Clinical Microbiology Laboratory, is a medical microbiologist who oversees lab diagnostic testing for patients. In this role Dr. Peaper advises Yale Medicine physicians about the pathogens—whether from bacteria, viruses, or fungus—detected in patient blood and urine samples.

In the field of infectious diseases, which range from well-known conditions such as pneumonia to meningitis to obscure illnesses that are rarely seen, technology has advanced at an astounding rate. “Today’s diagnostic tests can search for 20 viruses rather than just one in a patient’s sample,” Dr. Peaper says. That advantage is accompanied by a challenge: Avoid ordering too many diagnostic tests, which can be expensive for the patient and the lab. “It’s my job to work with clinical providers to identify ways the lab can improve care for their patients,” Dr. Peaper says. “Sometimes that means additional testing, but it can also mean saying no if the test is not appropriate.”  

While Dr. Peaper does not see patients in a clinical setting, he chose the field because he believes of his desire to help many people. He explains that his interest in laboratory diagnostic testing grew when he realized that he could impact patient care on a large scale by improving disease detection.

“Every urine culture done for patients at Yale New Haven Hospital goes through our lab—we see about 80,000 cultures a year,” Dr. Peaper says. “We constantly find ways to improve our workflow, so that physicians can treat their patients faster.”

As an assistant professor at Yale School of Medicine, Dr. Peaper has a strong research interest in rapid respiratory virus testing. He is also focused on avoiding antibiotic overuse, along with other topics related to lab tests and patient care.  





Affiliated With

Yale Medicine


Education & Training


Yale School of Medicine


Yale New Haven Hospital


Yale New Haven Hospital