At RWJF, Besser leads the largest private foundation in the country devoted solely to improving the nation’s health. RWJF’s work is focused on building a comprehensive Culture of Health that provides everyone in America with the opportunity to live the healthiest life possible, regardless of finances, geographic location, race, ethnicity, or physical challenges. Access to healthy food, safe housing, employment, transportation, education, as well as clean air and water, are all important contributors to health and well-being.        

In Besser’s role at ABC News, he provided medical analysis and reports for all ABC News programs and platforms. His weekly health chats on social media reached millions.

Before joining ABC News in 2009, Besser worked as director of the Coordinating Office for Terrorism Preparedness and Emergency Response at the CDC. In that role he was responsible for all the CDC's public health emergency preparedness and emergency response activities. He also served as acting director of the CDC from January to June 2009, during which time he led the CDC's response to the H1N1 influenza pandemic.

Besser’s tenure at the CDC began in 1991, working on the epidemiology of foodborne illness. He then served for five years on the faculty of the University of California, San Diego, as the pediatric residency director, while also conducting research and working for the county health department on the control of pediatric tuberculosis. He returned to the CDC in 1998 as an infectious disease epidemiologist working on pneumonia, antibiotic resistance, and the control of antibiotic overuse.

While at ABC News, Besser traveled all over the United States and around the globe to cover major medical news stories. He walked the Ebola wards in Liberia in 2014, reporting from the center of the deadly epidemic, and continued to provide extensive coverage for months. In 2011, he led ABC's global health coverage, Be the Change: Save a Life, reporting on critical global health issues from seven different nations.

The author or co-author of hundreds of presentations, abstracts, chapters, editorials and publications, Besser has earned many awards for his work in public health and for his volunteer service. He received the Surgeon General's Medallion for his leadership during the H1N1 response, and in 2011 he accepted the Dean's Medal for his contributions to public health from the Johns Hopkins Bloomberg School of Public Health. His investigative reporting into umbilical cord blood banking was nominated for an Emmy Award in 2011. In 2012, he received an Overseas Press Club award as part of ABC's coverage of global maternal health issues, and two Peabody Awards as part of ABC News’ coverage of Hurricane Sandy and Robin Roberts’ health journey. His book, Tell Me the Truth, Doctor: Easy-to-Understand Answers to Your Most Confusing and Critical Health Questions, was published by Hyperion in 2013.

Besser received his Bachelor of Arts degree in economics from Williams College and medical degree from the University of Pennsylvania. He completed a residency and chief residency in pediatrics at Johns Hopkins University Hospital in Baltimore. Read Less ^