Dr. van Seventer started her professional career as a veterinary practitioner, while taking part in research projects at the Woods Hole Oceanographic Institution and Marine Biological Laboratory. She subsequently received fellowship training in pathology and immunology at Harvard Medical School and the National Cancer Institute. Dr. van Seventer started her career as an independent investigator in the Department of Pathology at the University of Chicago, and joined the Department of Environmental Health at Boston University School of Public Health (BUSPH) in 2000. Her research at BU concentrated on characterizing the molecular mechanisms by which the human innate immune response regulate subsequent adaptive immunity. Research studies primarily focused on the role of type I interferons (IFN), IFN-alpha and IFN-beta, in regulating human dendritic cell and T cell functions, with emphasis placed on translating basic research findings to autoimmune diseases (multiple sclerosis (MS) and systemic lupus erythematosus (SLE)) and infectious diseases that result in septic shock.

In 2011, Dr. van Seventer turned her primary focus towards developing new curricula, new teaching strategies, and teaching courses in physiology and infectious diseases to students in the BUSPH, as well as to students in the joint BU Metropolitan College-College of Communication program, Online Master of Science in Health Communication. A particular teaching interest is in examining the role of the environment in infectious disease emergence and spread. Dr. van Seventer is director of the BUSPH Infectious Disease Certificate Program. She is also a co-leader of the Boston University Superfund Program Training Core, and a co-principal investigator of the Boston University Upward Bound Math and Science Program, a program whose purpose is to prepare low-income and first-generation college bound students for success in higher education. Current research is focused on identifying zoonotic pathways of antimicrobial resistance (AMR) in southwest coastal Bangladesh. In collaboration with colleagues from the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) and Tufts University, Dr. van Seventer and colleagues are addressing the potential for animal husbandry practices to increase AMR risk in humans by exposing households to pond water containing antibiotics and multidrug-resistant bacteria of animal origin.