Staff Bios

Rahel Abebe, M.H.S. (OAR)

Rahel Abebe, M.H.S. joined the Office of AIDS Research (OAR) in 2016 and currently serves as a public health analyst. She handles HIV/AIDS funding requests from NIH institutes, centers, and offices and coordinates workshops and a range of scientific program activities. Before joining OAR, Ms. Abebe was a health specialist in the Division of AIDS (DAIDS) at the National Institute of Allergy and Infectious Diseases, where she managed and coordinated non-network–funded grants, new initiatives, and the DAIDS Clinical Science Review Committee review process.

Elisabet V. Caler, Ph.D. (OAR)

Elisabet V. Caler, Ph.D. is a senior scientific advisor in the Office of AIDS Research (OAR), where she provides senior scientific and programmatic leadership to NIH’s coordinated HIV/AIDS research enterprise. At OAR, she helps shape NIH-wide priorities for HIV cure, diagnostics and technology advances, data integration, early career investigator development, research infrastructure, and community partnership. She also actively participated in the development of the FY 2026–2030 NIH Strategic Plan for HIV and HIV-Related Research. Prior to OAR, Dr. Caler served as a Program Director at the National Heart, Lung, and Blood Institute, where she directed an extramural portfolio of more than 200 active research and training grants in pulmonary infections, the lung microbiome, HIV/AIDS, and tuberculosis, while helping to launch over 12 strategic funding initiatives across emerging areas of biomedical science, including HIV initiatives.

Before joining NIH, Dr. Caler was an assistant professor of genomics at the J. Craig Venter Institute, leading genomics, metagenomics, transcriptomics, and infectious disease research. She earned her Ph.D. and M.Phil. in biomedical sciences from Yale University School of Public Health and her M.Sc. in molecular biology and biotechnology from the University of Buenos Aires. She completed postdoctoral training as a Fogarty fellow at the National Institute of Allergy and Infectious Diseases and as a postdoctoral research associate at the Boyer Center for Molecular Medicine at Yale University. Among an array of activities, she leads the OAR Technology Advances for HIV program and OAR Early Career Investigators in HIV Initiative and also acts as senior advisor for the OAR Community Partnership Program.

David Chang, Ph.D. (OAR)

David Chang, Ph.D. is a senior science advisor and the acting leader of the Science Team at the Office of AIDS Research (OAR). In this role, he leads the team that provides technical and scientific expertise in support of OAR’s efforts to shape NIH’s HIV research priorities and coordinate HIV research across the agency. Dr. Chang joined OAR in 2023, bringing significant experience in preclinical vaccine development and HIV molecular epidemiology. In addition to his current role leading the OAR Science Team, Dr. Chang supports coordination of the NIH-wide HIV research portfolio and provides scientific and programmatic leadership in priority research areas. He leads the OAR HIV and Aging Signature Program, which aims to advance research to identify and address the long-term health needs of people aging with HIV, including older adults with HIV and lifetime and long-term survivors. Dr. Chang also leads the OAR Early Career Investigators program, which supports the next generation of HIV researchers by providing resources on the NIH grant application and review processes and networking opportunities.

Before joining OAR, Dr. Chang served as a scientific review officer at the National Institute of Allergy and Infectious Diseases and the Center for Scientific Review. Prior to joining NIH, he worked in the biotechnology sector on preclinical viral vaccine development before earning his Ph.D. from the Uniformed Services University of the Health Sciences, where his research focused on HIV-1 envelope glycoproteins, broadly neutralizing antibodies, and disease progression. He then served as a research scientist with the U.S. Military HIV Research Program at the Walter Reed Army Institute of Research, where he investigated HIV molecular epidemiology in Asia and Africa and contributed to studies of viral genetics and central nervous system compartmentalization during acute HIV infection.

Adia McCray (OAR)

Adia McCray is a program specialist in the Office of AIDS Research (OAR). Her formal education emphasized business administration and project management. Therefore, she is knowledgeable in management procedures and policies that cover intercultural communication and leadership, statistics and data analysis for managerial decision-making, and financial decision-making for managers. In addition to OAR, Ms. McCray has worked at the Eunice Kennedy Shriver National Institute of Child Health and Human Development and in the Division of Program Coordination, Planning, and Strategic Initiatives’ Immediate Office of the Director, allowing her to effectively and efficiently work with all levels of management and administrative staff. Her various experiences have helped enhance her management knowledge and skills by assisting with several management assessments to ensure organizations operate to their maximum capacity. She is adept at offering the advice needed to make organizations more effective and efficient. Through her work experience and formal education, she has gained knowledge in the areas of project management, quality management, procurement, and financial and strategic analysis.

Hayatt Mohamed, M.P.H. (The Scientific Consulting Group)

Hayatt Mohamed, M.P.H. is a contractor for The Scientific Consulting Group, Inc., who serves as a public health analyst within the Office of AIDS Research (OAR). At OAR, she is a member of the Analytics and Evaluation team, where she provides analytical support for the HIV and Aging focus area; early career investigator development efforts; and portfolio analyses for the Ending the HIV Epidemic in the U.S. initiative and HIV and Coinfections initiative. Before joining OAR in February 2022, Ms. Mohamed was a research specialist for the Multicenter AIDS Cohort Study/Women’s Interagency HIV Study Combined Cohort Study (or MWCCS) at Whitman-Walker Health. She was previously a consultant for CommonHealth ACTION and supported the American College of Obstetricians and Gynecologists Council on Patient Safety in Women’s Health Care. Ms. Mohamed obtained an M.P.H. from The George Washington University, with a concentration in epidemiology, and a B.A. in anthropology from the University of Maryland, College Park.

Julie Pulerwitz, Sc.M., Sc.D. (OAR)

Julie Pulerwitz, Sc.M., Sc.D., is a senior science advisor in the National Institutes of Health (NIH) Office of AIDS Research (OAR), where she oversees implementation science program efforts and leads the NIH-wide Advancing Research in Implementation Science to End HIV (ARISE-HIV) initiative. Through ARISE-HIV, she coordinates HIV implementation science across all NIH Institutes, Centers, and Offices to accelerate progress toward ending the HIV epidemic. ARISE-HIV advances research agenda–setting, funding opportunities, and capacity-building efforts to strengthen the implementation science workforce and catalyze impact nationwide.

Dr. Pulerwitz brings more than 25 years of experience in HIV implementation science and socio-behavioral research to this effort. Before joining OAR, Dr. Pulerwitz directed HIV initiatives at the Population Council and for the Investigators in the Pathogenesis of Infectious Disease (or PATH) program and has held senior leadership and advisor roles at the DC Center for AIDS Research, HIV Prevention Trials Network, and U.S. Agency for International Development Male Engagement Task Force. She also advised the World Health Organization, the Joint United Nations Programme on HIV/AIDS (or UNAIDS), and other global partners, bringing strong experience in strategic leadership and research translation to her role at OAR.

Dr. Pulerwitz has published, taught, and presented widely in the areas of HIV prevention and care, social and behavior change, mental health, gender norms, stigma, violence, and other social determinants of health. She has developed and validated several globally used scales to measure such complex social constructs as HIV stigma and resiliency and couple negotiation. She also has conducted research in more than 20 countries across Latin America, the Caribbean, Asia, and Africa, in addition to the United States. Dr. Pulerwitz received her B.A. from the University of Pennsylvania and her master’s and doctoral degrees from the Harvard T.H. Chan School of Public Health.