As the World Health Organization (WHO) prepares for a major transition in its executive leadership on June 16, 2025, Director-General Dr. Tedros Adhanom Ghebreyesus has extended heartfelt gratitude to several senior officials whose tenure is coming to an end. Their collective contributions, he noted, have shaped the organization’s response to global health emergencies and laid the foundation for long-term reforms in public health governance.

Foremost among the departing leaders is Dr. Michael J. Ryan, Deputy Director-General and Executive Director for Health Emergencies, Preparedness, and Response. Dr. Ryan, widely recognized for his pivotal role during the COVID-19 pandemic, had originally intended to step down two years ago but remained at Dr. Tedros’ request. Describing him as a steady presence during WHO’s most challenging moments, Dr. Tedros credited Dr. Ryan for transforming emergency response operations with compassion and strategic insight.

Another key figure stepping down is Dr. Bruce Aylward, Assistant Director-General for UHC/Life Course. Dr. Aylward played a central role in managing responses to public health threats like Ebola and COVID-19. He is especially noted for forging global partnerships through the Access to COVID-19 Tools Accelerator (ACT-A) initiative and guiding the development of WHO’s Fourteenth General Programme of Work (2025–2028).

Dr. Samira Asma, Assistant Director-General for Data, Analytics, and Delivery for Impact, is also departing. She was instrumental in embedding data and evidence at the core of country-level impact strategies and helped establish the WHO Data Hub, a cornerstone for transparency and accountability.

Dr. Catharina Cora Boehme, Assistant Director-General for External Relations and Governance, leaves behind a legacy of innovation in financing and governance. She led WHO’s first-ever Investment Round aimed at securing sustainable funding and earlier served as Chef de Cabinet.

Also among those departing is Dr. Li Ailan, Assistant Director-General for UHC/Healthier Populations, whose leadership ensured that prevention and population health remained central to WHO’s agenda. With experience at both country and regional levels, she championed initiatives targeting lifestyle-related health issues.

Dr. Jérôme Salomon, Assistant Director-General for UHC/Communicable and Noncommunicable Diseases, is credited with bridging gaps between communicable and noncommunicable disease agendas. His integrated approach to mental health, neglected tropical diseases, and broader health systems strengthened WHO’s capacity to respond holistically to global health challenges.

As WHO turns the page to a new leadership team, Dr. Tedros concluded his message by thanking the outgoing executives for their unwavering commitment and outstanding service.

“Their leadership has left a lasting impact on global health and on WHO’s ability to serve the world’s most vulnerable,” he said.