Our People

Kate O’Brien, MD, MPH

Executive Director

Dr. O’Brien leads IVAC’s faculty and staff to generate vaccine evidence, support vaccine policy formulation, and advance vaccine access, coverage and equity through a portfolio of projects at the global, regional and in-country settings.

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William Moss, MD, MPH

Deputy Director

Dr. Moss is the co-Principal investigator of the Strengthening Immunization Systems through Serosurveillance (SISS) project funded by the Bill & Melinda Gates Foundation to assess the feasibility and utility of serological surveillance to guide immunization programs.

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Dagna Constenla, PhD, MPhil, MPH

Director of Economics & Finance

Dr. Constenla is a senior scientist with over 20 years of experience in the global sector conducting economic and health service research.

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Lois Privor-Dumm, IMBA

Director of Policy, Advocacy & Communications

Ms. Privor-Dumm leads Policy, Advocacy, and Communications efforts on a variety of projects at country, regional, and global level, including advocacy and capacity building in low- and middle- income countries.

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Naor Bar-Zeev, PhD, MPH

Director of Epidemiology

Associate Professor Dr. Naor Bar-Zeev is an Australian-trained clinical academic with 20 years of experience in global child health across East Asia, the Pacific, and Africa.

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Patricia Hahn-Esposito

Director of Operations

Ms. Hahn-Esposito is the financial manager that oversees financial & administrative management of IVAC projects and personnel.

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Maria Deloria Knoll, PhD

Associate Director for Science

Dr. Knoll is an epidemiologist with a focus on the technical analytical challenges for policy-driven research pertaining to the design, conduct, and analysis of epidemiological studies and clinical trials that evaluate vaccines and vaccine-preventable diseases.

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Mathuram Santosham, MD, MPH

Senior Advisor

Dr. Santosham is the senior advisor at IVAC and helps to formulate and guide IVAC’s strategies and mission.

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