Mary Ann South, former associate professor of pediatrics at Children’s Hospital of Pennsylvania who went on to be a member of the team of doctors who cared for David Vetter, known as “the boy in the bubble,” died November 7 in her New Mexico home. She was 86.

After graduating from Portales High School in 1951, she attended Eastern New Mexico University, graduating in 1955. She then went to Baylor College of Medicine in Houston, where she received her MD in pediatrics in 1959. Dr. South completed her internship at St. Luke’s Hospital in Chicago, a residency in infectious disease at Baylor, and a fellowship in pediatric immunology from the University of Minnesota.

In 1973, she joined the faculty at CHOP as an associate professor of pediatrics. She left CHOP in 1977 and went on to work in the department of pediatrics at Texas Tech University Health Sciences Center; then as a visiting professor with the National Institutes of Health; and finally as the Kellogg Endowed Professor of Medicine at Meharry Medical College in Nashville, Tennessee, one of the few historically black medical schools in the county.

Dr. South’s expertise was in pediatrics, infectious diseases and pediatric and adult immunology. During her career, she was involved in major breakthroughs involving how the rubella virus in babies causes immune defects, the differentiation of immune cells, and the treatment of babies born with significant immunological systems. It was during her time as an assistant professor at Baylor College of Medicine that South came to know and help care for David Vetter. As a result of her work and that of her colleagues, the overwhelming majority of infants diagnosed with severe combined immunodeficiency (SCID) are now successfully treated with bone marrow transplants.

Dr. South is survived by step-children, step-grandchildren and step–great grandchildren.