Merceditas S. Villanueva, MD


Infectious Disease, Internal Medicine

(203) 688-5303
Telehealth Visits


Merceditas S. Villanueva, MD, director of the Yale Medicine AIDS Care Program, is an infectious disease specialist with a clinical focus on HIV and AIDS. She cares for patients in the hospital who are sick with various infections (e.g. pneumonia) as well as those with complications of HIV. She also treats patients in the Nathan Smith Clinic, where she primarily treats HIV.

As a clinician, Dr. Villanueva believes in getting to know each patient as an individual. “I think that way you really make a difference in people's lives,” she says. While people with HIV are from different backgrounds, she often learns that her patients need advice on resources beyond medical care. “Sometimes we think it has to be this huge thing that you do for people. But it's the little things that you notice that will make a difference—the ability to hear them, the ability to link them to the right resources if they need it.”

Dr. Villanueva was drawn to the field of infectious diseases after being exposed to a variety of populations throughout her childhood, traveling to different countries with her father, who worked for the United Nations. She saw many people who struggled with diseases that called not only for medical care, but also attention from a public health standpoint. “I always felt that it would be great to make an impact in those communities,” Dr. Villanueva says. HIV and AIDS was an area that pulled all those interests together.

AIDS was a uniformly fatal disease when Dr. Villanueva was a medical student in the early 1980s. In the last two to three decades, increasingly better care and treatment has made HIV a chronic disease. “The message that we gave patients in the early days was, ‘Let's try to make your remaining days as comfortable as possible.’ But that message has totally changed. It's not curable, but as long as people take their medications, it’s controllable, so people living with HIV can lead, more or less, normal lives.” As such, doctors and researchers are turning their attention to people with HIV who are surviving into their 50s and 60s.

Dr. Villanueva is an associate professor of Medicine at Yale School of Medicine. Before coming to Yale, she founded the Ryan White-funded HIV clinic at Waterbury Hospital, and she now serves as the principal investigator for the New Haven Ryan White HIV Continuum, a collaboration between clinics and community organizations that promotes service coordination to improve quality of care for HIV patients, particularly those that are underserved. She works closely with community-based AIDS organizations and providers throughout Connecticut, and her research focuses on optimizing models of care that capitalize on partnerships between the medical establishment and community support.





Affiliated With

Yale Medicine


Education & Training


Washington University


Muhimbili Medical Center;Duke University


Yale University School of Medicine

Accepted Insurance

Insurance coverage regularly changes, please contact the doctor’s office directly to verify that your specific insurance plan is accepted.

  • aetna
  • anthem bc/bs
  • berkeley care network
  • cigna healthcare
  • community care network
  • connecticare
  • corvel
  • first health network
  • focus healthcare
  • great west
  • husky
  • medicaid
  • medicare
  • multiplan
  • oxford health plans
  • railroad medicare
  • tricare/champus
  • united healthcare
  • us family health plan
  • wellcare