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Dr. John N. Nkengasong
U.S. Global AIDS Coordinator and Special Representative for Health Diplomacy

Dr. John N. Nkengasong was confirmed by the U.S. Senate as the U.S. Global AIDS Coordinator and Special Representative for Health Diplomacy (S/GAC) on May 5, 2022, and officially sworn in on June 13, 2022.  In this role, Dr. Nkengasong leads, manages, and oversees the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR) – the largest commitment by any nation to address a single disease in history. Born in Cameroon, Dr. Nkengasong is the first person of African origin to hold this position.

In 2017, Dr. Nkengasong was appointed as the first Director of the Africa Centres for Disease Control and Prevention (Africa CDC) headquartered in Addis Ababa, Ethiopia. Through his leadership, a framework for moving Africa CDC into a full autonomous health agency of the Africa Union was established. Dr. Nkengasong also led efforts to create policy frameworks to guide countries to establish and strengthen their public health institutes and defined and implemented a system to collate national surveillance data.

Dr. Nkengasong served as the Chief of the International Laboratory Branch, Division of Global HIV/AIDS and Tuberculosis, and subsequently as the Acting Deputy Director at the Center for Global Health, U.S. Centers for Disease Control and Prevention (CDC).  He also served as the Associate Director for Laboratory Science, Division of Global AIDS/HIV and Tuberculosis, Center for Global Health, CDC, and Co-Chair of the PEPFAR’s Laboratory Technical Working Group.  As a leading virologist with over 30 years of experience in public health, Dr. Nkengasong was appointed as a board member for the International AIDS Vaccine Initiative in New York, and the Coalition for Epidemic Preparedness Innovation, in Norway.

He received his B.Sc. from the Faculty of Science, University of Yaoundé, Cameroon; his M.Sc. from the Institute of Tropical Medicine, Antwerp, Belgium; and his Ph.D. from the Faculty of Medicine, University of Brussels, Belgium.  He also received a Diploma in Leadership and Management from the Kennedy School of Government at Harvard University.

Dr. Nkengasong is the recipient of numerous prestigious awards and recognitions. Most recently, he served as one of the World Health Organization Director General’s Special Envoys for COVID-19.  In 2021, Dr. Nkengasong was recognized as Time Magazine’s 100 Most Influential People where he was described as “a modern-day hero”. Additional awards include the US Secretary of Health and Human Services Award for Excellence in Public Health Protection Research, the Shepard Award, the US Director’s Recognition Award, and the William Watson Medal of Excellence, the highest recognition awarded by CDC. Awarded for outstanding contributions and leadership in advancing global laboratory services and programs to support the President’s Emergency Plan for AIDS Relief.  He has authored or co-authored over 250 peer-reviewed papers and book chapters in professional journals.

Dr. Angeli Achrekar, DrPH, MPH
Principal Deputy U.S. Global AIDS Coordinator

Dr. Angeli Achrekar serves as the Principal Deputy U.S. Global AIDS Coordinator, a Principal Deputy Assistant Secretary level position. As such, she serves as the second in command to the U.S. Global AIDS Coordinator and supports the daily oversight, coordination, leadership, management, and implementation of the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR) to ensure that all its activities and resources, including its annual budget of approximately $6 billion in over 50 countries are as impactful, effective, and efficient as possible.

In this role, Dr. Achrekar works with leaders across the State Department’s Office of the Global AIDS Coordinator (S/GAC) and among the seven federal agencies that implement PEPFAR to ensure effective and efficient management, coordination, and program implementation. In addition, she ensures that Congress, the Office of Management and Budget, and the administration are kept informed on program results. She also acts on behalf of the U.S. Global AIDS Coordinator in her absence. Prior to this current role, she served as PEPFAR’s Chief of Staff and most recently as the Deputy Coordinator for Strategy and Global Health Diplomacy, where she oversaw PEPFAR’s public affairs, policy, and congressional efforts, including PEPFAR’s reauthorization, as well the adolescent girls and young women’s portfolio and the global health diplomacy efforts.

Dr. Achrekar has dedicated her career as a public servant to global HIV/AIDS, women and girls’ health, and global public health development. After working in India and later with UNICEF headquarters on adolescent health, she accepted a position with the U.S. Centers for Disease Control and Prevention (CDC) in 2001, where she focused on integrated adolescent health programs and services. She led the interagency and multidisciplinary National Initiative to Improve Adolescent Health, which created strategic partnerships between the health and education sectors comprising over 100 organizations, agencies, and professional associations in the U.S. to improve the health, safety, and well-being of youth ages 10-24. Since 2003, Achrekar has been working on PEPFAR’s global HIV/AIDS efforts. In 2005, she went to South Africa to help local governments plan and implement a rapid assessment of drug use and sexual HIV risk patterns among injecting and non-injecting drug users and sex workers in Durban, Pretoria, and Cape Town. After serving as a Country Officer, she became the Senior Public Health Manager, supporting cross-cutting, system-wide sustainability activities and strategies in CDC’s Division of Global HIV/AIDS. In 2011, she joined the U.S. Department of State and helped lead the conceptualization and development of Saving Mothers, Giving Life as well as facilitated the implementation of this important program – a public-private partnership that impacts maternal and neonatal health and HIV services.

Achrekar holds a Doctorate in Public Health from the University of North Carolina at Chapel Hill, a Master of Public Health from Yale University, and a Bachelor of Science from the University of California, Los Angeles. She studied Spanish while living in Santiago, Chile, and in Mendoza, Argentina. She has lived and worked in numerous countries and speaks multiple languages.

William Dilday
Interdepartmental Liaison

Bill Dilday serves as the Interdepartmental Liaison in the Office of the U.S Global AIDS Coordinator and Health Diplomacy (S/GAC).  The office implements the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR).  With an annual budget of approximately $6 billion, PEPFAR is the largest commitment by any nation to combat a single disease in history.  Bill advocates for and raises awareness and visibility of S/GAC and PEPFAR within the Department.  He creates partnerships and serves as a resource and point of contact for Department entities on S/GAC and PEPFAR and vice versa.  From August 2018 to July 2020, Bill served as the Chair of PEPFAR’s West Africa Regional program.

Having joined S/GAC at its establishment in 2003, Bill is the longest serving member of the S/GAC staff.  Until 2016, he served as S/GAC’s Executive Director, leading operational and administrative support for S/GAC, including human resources, facilities management, information technology, general services, and travel, within an annual budget of $17 million.

From 2002 to 2003, Bill served as a deputy director and senior regional advisor in the Department’s Office of International Health and Biodefense, working on public health issues, including HIV/AIDS and SARS, in Asia, the Pacific, and other regions.

In 2001-2002, Bill was the director of the Office of Country Reports and Asylum Affairs in the Department’s Bureau of Democracy, Human Rights and Labor.  He served as editor-in-chief of the Department’s 2001 and 2002 Country Reports on Human Rights Practices, the 2001 International Religious Freedom Report, and contributed to the Department’s first Trafficking in Persons Report.  Bill also coordinated the Department’s review of approximately 125,000 annual applications for asylum in the United States and issued the Department’s advisory opinions to U.S. immigration judges adjudicating such claims.

From 1996 to 2001, Bill served as the special advisor for East Asian and Pacific Affairs in the Department’s Oceans and International Environmental and Scientific Affairs Bureau.  During 1996-1997, he also served as the special advisor for South Asian, Near Eastern and African Affairs in the same bureau. From 1990 to 1996, he served in the Department’s Office of Marine Conservation and was responsible for fisheries negotiations with Canada, Russia, China, Japan, and South Korea, as well as in the United Nations.

A career civil servant, Bill joined the Department in 1989, initially serving as a student intern in the Bureau of Legislative Affairs. Bill is the recipient of four Meritorious Honor Awards, four Superior Honor Awards, and was a nominee for the Department’s award for Outstanding Achievement in Global Affairs. A Springfield, Missouri native, Bill is a 1989 graduate of Missouri State University.

Brendan T. Garvin
Director of Management and Budget

Brendan Garvin joined S/GAC in 2019 as the Director of Management and Budget. He also serves as Chair for the PEPFAR program in Ukraine.

Prior to joining S/GAC, Brendan worked in the Office of U.S. Foreign Assistance Resources (F), which is the State Department office responsible for the broader foreign assistance budget, including PEPFAR funds.  Prior to F, he worked in the Bureau for Political Military Affairs on military assistance programs.  He also has prior experience working in the Department of Defense on security cooperation programs.  Brendan received a BA in Biology and Political Science from Rice University.

Julia Martin
Senior Health Advisor & U.S. Representative to the Global Fund

Julia Martin is the Senior Health Advisor and U.S Representative to the Global Fund posted to Geneva, Switzerland.  In this role, Julia principally represents the interests, advances the agenda of S/GAC, and supports the Office of Global Affairs/HHS in their engagement on the Global Fund Board.   She works closely with multi-lateral global health partners on the effective use of public funds for HIV and forward leaning strategies to improve health delivery systems and public health outcomes.  Ms. Martin works collaboratively with leadership and staff in the Global Fund for HIV, TB and Malaria, UNAIDS and WHO.  Working as part of the U.S. Mission Geneva Health Team, Julia is part of and has access to broader health agendas that both inform the work of S/GAC and PEPFAR and offer opportunities to advance the global HIV agenda.

Julia has been part of the PEPFAR team within S/GAC for over 10 years previously holding positions of Deputy Coordinator for Program and then Program Quality, as well as four years as Chief Operating Officer responsible for budget, multilateral affairs, country program support, technical leadership and human resources.

Julia has over 25 years of professional experience in health with a focus on global public health and HIV/AIDS. She has held positions in the public and not-for-profit sectors and has worked closely with foundations, large private sector corporations and pharma. She brings leadership in the areas of program and policy development across multiple populations and in many countries. Working in disease prevention and treatment, she has extensive experience in developing global and national HIV policy and designing healthcare delivery systems in mid-level and developing economies.  She has sat on and chaired many committees and initiatives, and more recently, several within the multilateral sphere representing the USG interests and positions.

William S. Paul, MD, MPH
Deputy Coordinator for Program Quality

Dr. Bill Paul joined S/GAC in 2019 as Deputy Coordinator for Program Quality. He also serves as Chair for the PEPFAR programs in Nigeria, Haiti & Dominican Republic.

Before joining S/GAC, Bill had a 27-year career in domestic public health practice and leadership.  From 2007-2018 he served as director of the Metro Nashville Public Health Department, leading 500 staff serving a population of over 600,000.  From 1992-2007 he served in the Chicago Department of Public Health where he strengthened core capacities in communicable disease control, TB, environmental health, and epidemiology and served briefly as acting commissioner.

A physician trained in internal medicine and infectious diseases, Dr. Paul served at CDC from 1990-1992 as an Epidemic Intelligence Service (EIS) officer, assigned to the Division of Vector-Borne Infectious Diseases.

Jirair Ratevosian, MPH
Acting Chief-of-Staff and Senior Advisor

Jirair Ratevosian joined S/GAC in August of 2021.  He serves as the only political appointee in the office, responsible for building and maintaining political relations across relevant U.S. government agencies and Department of State offices in service of PEPFAR.  He is currently managing the PEPFAR 5-year strategy development, Global Fund matters, as well as other programmatic support areas. He also serves as Chair for the PEPFAR program in South Africa.

Prior to joining S/GAC, Jirair was Executive Director at Gilead Sciences where he led government and multilateral engagement for a portfolio that included global health, Africa, Asia, Central America and Caribbean.  Through his time at Gilead, he built collaborative partnerships with the African Union, Africa CDC, as well as the Organization of African First Ladies for Development. Prior to joining Gilead, he served as Legislative Director to Congresswoman Barbara Lee (D-CA), where he led the foreign policy and public health portfolio and advised on legislative issues that included the reauthorization of PEPFAR in 2013. He has held positions and board appointments with The Global Fund, amfAR, American Public Health Association, Physicians for Human Rights, and Center for Democracies in the Americas.

Jirair is currently pursuing a doctoral degree in health diplomacy from Johns Hopkins University School of Public Health.

Mike Ruffner
Deputy U.S. Global AIDS Coordinator for Financial and Programmatic Sustainability

Michael Ruffner is the Deputy Coordinator for Financial and Programmatic Sustainability in the Office of the Global AIDS Coordinator (OGAC) at U.S. Department of State.   He is working to better integrate and improve the effectiveness of existing funding for HIV, while working with countries to improve their ability to operate and finance HIV response on their own.  He is leading the new PEPFAR effort to engage partner country Finance Ministries in the fight against HIV and in the investment into resilient and financially secure health systems. He currently is OGAC chair for the Kenya and Lesotho programs.  In addition to his functional and programmatic responsibilities, Michael is the chair of the Board of Director’s Audit and Finance Committee of the Global Fund for the Fight against AIDS, TB and Malaria.

Michael joined OGAC on detail from the US Department of the Treasury during 2015.  After returning to Treasury, in October 2016, Michael joined OGAC and the Department of State full time.  Immediately prior to his appointment to the PEPFAR program, for ten years Mr. Ruffner was the Director of Treasury’s Office of Technical Assistance where he lead a team of over 200 advisors providing capacity building to Finance Ministries, Central Banks, Revenue authorities and related entities. He also launched the Treasury technical assistance effort to the Commonwealth of Puerto Rico during the 2016 bankruptcy and was involved in a number of special initiatives, including the Energy Governance and Capacity Initiative.

Michael has held positions at the OECD Paris, the U.S. Senate Agriculture Committee, the U.S. Senate Budget Committee and was a Presidential Management Intern at the Office of Management and Budget.  Michael, a native of Michigan, has an undergraduate degree from Michigan State University and a graduate degree in Public Policy from the University of Michigan.

Vickie R. Walker
Executive Director

Vickie serves as the Executive Director in the Office of the U.S. Global AIDS Coordinator, leading the operational and administration support for SGAC, including human resources, information technology services, facilities management, and travel within an annual budget of $17 million.

In this role, Vickie also leads key efforts to provide improved human resource organizational staffing to a multi-faceted staff of personnel, including Department of State Civil Servants, Foreign Service Officers, Interagency Detailed Personnel and State Contract Personnel.

Vickie has led and directed the PEPFAR Limited Non-Career Appointment (LNA) Program and instrumental in developing guidelines and internal policies to transition critical PEPFAR Country Coordinator positions in PEPFAR Countries globally. In this role, she works in collaboration with PEPFAR Country Ambassadors, Deputy Chiefs of Missions, S/GAC country and accountability leads to recruit and hire foreign service officers who represents the United States and manage critical foreign assistance programs in foreign countries.

Vickie has dedicated her life as a public servant with 24 years actively serving in the United States Army in the U.S. and abroad.  After honorably retiring from the U.S. Military service, she began work in the Office of the U.S. Global AIDS Coordinator in 2005 and has served in several positions culminating to her current role as the Executive Director.
She attended the University of Maryland (Germany) earning a degree in Psychology, later earning a Masters in Human Resources and Development (MHRD) and a Master of Business Administration (MBA).

Mamadi Yilla
Deputy U.S. Global AIDS Coordinator for Multisector Relations

Mamadi Yilla, Ph.D. is the new Deputy Coordinator for Multisector Relations spearheading partnership efforts with multilateral partners and the private crafting, fostering, and solidifying wide-ranging public-private partnerships to leverage USG investments with businesses and private foundations, and collaborate with key multilateral institutions to ensure program implementation is complementary and synergistic for maximum impact.

Previously she served jointly as Deputy Coordinator for Multisector Responsibility and Diplomacy, and as the Acting Deputy Coordinator for Strategy and Global Health Diplomacy at S/GAC, overseeing the Managing Directors for Communications, Congressional Relations, Multilateral Affairs, Private Sector Engagement and Global Health Diplomacy at PEPFAR, the U.S. President’s Emergency Plan for AIDS Relief. PEPFAR is a $6.9 billion dollar per year foreign assistance program to end AIDS. As an executive officer for the program, Mamadi is at the forefront of the Department of State’s health and diplomacy mandates through external engagement with a broad array of stakeholders.

Mamadi has served PEPFAR for fifteen years holding various roles at the country level and in Washington D.C. As a key strategist for the program, she manages over $1.56 billion per year in U.S. contributions to the Global Fund for AIDS, TB and Malaria, and facilitates the U.S. interagency delegations to the Global Fund and UNAIDS Boards and provides direct oversight for ~$600 million in PEPFAR funding to Zambia and Malawi. In 2021, she leads the oversight and accountability for $3.5 billion in resources through the American Rescue Plan to the Global Fund for COVID-19.

She joined S/GAC in 2011, as Director for Sustainability and Integration while promoting the U.S. government’s goals to advance the priorities of country ownership and sustainability under PEPFAR and the Global Health Initiative. In 1997, prior to PEPFAR, she served at the Centers for Disease Control and Prevention as a research fellow in immunology, improving diagnostic tools for vaccine-preventable childhood diseases, and publishing CDC studies on the SARS-CoV outbreak of 2003.

Born and raised in Sierra Leone, Mamadi was educated in Sierra Leone and the United Kingdom before immigrating to the United States as a teenager. She received undergraduate and graduate training at the State University of New York at Buffalo and post doctorate training at MIT in Cambridge, Massachusetts. Mamadi is married and the mother of three college-aged daughters, one a recent graduate from Penn State University and two seniors at Harvard University.

Irum Zaidi
Deputy Coordinator of Program Results and Impact Monitoring for Epidemic Control

Irum serves as Deputy Coordinator for Program Results and Impact Monitoring for Epidemic Control (PRIME) at the U.S Department of State’s Office of the U.S. Global AIDS Coordinator and Health Diplomacy (S/GAC), which leads and coordinates the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR). She is an Epidemiologist by training and has been part of the S/GAC leadership team for over five years working on PEPFAR’s global HIV/AIDS efforts. She has devoted her career to the control of infectious diseases focusing on HIV/AIDS.  At S/GAC, she has utilized her position to implement innovative infectious disease control strategies using granular data, establishing innovative health information systems and community engagement. She has led the global health data revolution and is recognized for her focus on epidemiologic impact and data use.

Working across more than sixty countries, Irum brings global insight into implementing public health policies at home and across Africa, the Caribbean, and Asia. She worked with the Kingdom of Saudi Arabia on the H1N1 pandemic for disease control during the Hajj. In 2020, she served on the White House Coronavirus Task Force working across the USG agencies, state and local health departments and communities.

In 2015, Irum received the Meritorious Honor Award for creating a revolutionary approach to utilizing programmatic, financial, and epidemiologic data to help inform how and where PEPFAR should invest its annual $4B budget. As a part of an international team of experts and decision-makers, she is credited for re-designing the Country Operational Program and fostering a renewed interest in the full utilization of data to improve decision-making and to enhance program focus. She is passionate about the nexus where government, community and private sector intersect to achieve public health outcomes.

Before joining S/GAC, Irum worked at the CDC beginning in 1998 as an Epidemiologist in numerous capacities. She served as a Strategic Information Advisor for PEPFAR countries while working in the Division of Global HIV and TB. She also served as Team Lead for the Clinical Surveillance team bringing new surveillance technologies to global settings.  Her experiences in domestic HIV policy, including several leadership roles across CDC’s domestic HIV surveillance programs, formed the basis for her unique approach to data utilization to create the greatest community impact.  Irum was the recipient of numerous awards during her time with CDC.

Irum graduated from Emory University with a Master of Public Health degree in International Health and Epidemiology and a Bachelor of Arts degree in Psychology.

U.S. Department of State

The Lessons of 1989: Freedom and Our Future