Leadership
Barry Zimmerman
Director of the Ventura County Health Care Agency
Barry Zimmerman has been serving as the Agency Director since 2021. Over his distinguished 28-plus years of service at the County of Ventura, he has held various executive leadership positions.
Previously, as the Director of the Ventura County Human Services Agency, Zimmerman’s leadership led to remarkable growth and the expansion of in-person services across the county. He brings extensive experience from his work at the state and national levels, earning wide recognition, notably receiving the Executive Leadership Award for his contributions to advancing Human Services in California.
Moreover, Zimmerman served as the past chair of the inaugural state-wide joint powers authority for all 58 counties. Under his guidance, this authority oversaw one of the state’s most significant automation projects for the human services system.
In his current role as Director, Zimmerman focuses on strategic planning and growth, policy development, government and community relations, as well as operational, financial, and performance improvement initiatives.
John Polich
Deputy Director of Government and Regulatory Affairs
John Polich joined the Health Care Agency in 2022 as Deputy Director, Government and Regulatory Affairs.
Previously, Polich worked for 20 years for the Ventura County Counsel, where he advised the Agency on legal matters including the designation of Ventura County Medical Center as a regional trauma center, formation of a county-operated Medi-Cal managed care system, and organization of the Health Care Agency’s ambulatory care clinics as a federally qualified community health center.
Prior to joining the County of Ventura, Polich worked for the law firm of Sidley Austin LLP, where he advised clients on corporate and taxation matters. He is a graduate of the University of Redlands and the Gould School of Law at the University of Southern California. Prior to attending law school, Polich worked as a journalist for regional newspapers in Ventura and Los Angeles counties.
Paul Jaconette
Director of Strategy and Business Development
Paul Jaconette is a seasoned healthcare leader and the Director of Strategy and Business Development at the County of Ventura Health Care Agency (VCHCA).
Jaconette holds a Bachelor of Arts Degree in Cell Biology and Human Physiology from UC Santa Barbara, along with a Master of Public Health/Health Care Administration degree from Yale University School of Public Health. His skills were further honed through an Administrative Fellowship at Intermountain Healthcare.
With over a decade as COO of CenCal Health, a Medi-Cal Health Plan covering Santa Barbara and San Luis Obispo Counties, he managed a membership of over 200,000. Previously, he held an 18-year role as Executive VP at Sansum Clinic, a significant nonprofit multi-specialty group practice. His experience also extends to management positions at Intermountain Healthcare and Kaiser Permanente Northern California.
In academia, he contributes as an adjunct faculty member at the University of California, Santa Barbara, teaching an honors seminar on the U.S. healthcare system. He is also certified in Coaching for Life and Work from UC Davis, providing leadership and management coaching.
Mike Taylor
Chief Financial Officer
After obtaining his Bachelor of Science in Business Administration (BSBA) from the University of Missouri, Taylor joined KPMG as an auditor. During his time at KPMG, he passed the CPA exam and gained valuable audit experience, including working with the University of California San Francisco Medical Center and other healthcare organizations.
Over the next 18 years, Taylor advanced his career in the healthcare sector, holding leadership roles at Alexian Brothers Health System and Via Christi Health System. During this time, he also pursued and completed his Master’s in Business Administration from the University of California at Davis.
From 2011 to 2019, Taylor served as the Chief Financial Officer (CFO) for Dignity Health Northridge Hospital Medical Center. In 2020, he assumed the role of CFO for the Ventura County Healthcare Agency.
Charles Flood
Compliance Officer
John Fankhauser, MD
CEO of Ventura County Medical Center and Santa Paula Hospital
Throughout his career, Dr. John Fankhauser has held various physician executive positions, including Chief Medical Officer (CMO) for VCMC and CMO of Santa Clara Valley Medical Center in San Jose.
Prior to 2007, he served as a full-time faculty member for the nationally renowned Ventura Family Medicine Residency Program. From 2013 to 2018, Dr. Fankhauser and his family were actively engaged in a medical mission in Liberia, where he served as the CEO of ELWA Hospital. During this time, the hospital played a crucial role in responding to the Ebola crisis.
Dr. Fankhauser graduated with honors from the University of Washington School of Medicine and is a member of the Alpha Omega Alpha Honor Medical Society, recognizing his outstanding achievements. He also holds a Master of Healthcare Administration from the University of Minnesota.
Theresa Cho, MD
CEO and Medical Director of Ambulatory Care
Dr. Theresa Cho’s extensive leadership experience, including as the Director of the Las Islas Diabetes Center and as the Medical Director for Quality, has strengthened her dedication to advancing population health in Ventura County. She is committed to ensuring that all patients have access to high-quality healthcare.
Dr. Cho is board certified in Family Medicine and completed her residency training at the Ventura County Medical Center (VCMC). She has worked as a hospitalist at VCMC and later joined the residency faculty. As an award-winning teacher of residents, she also leads the hospital diabetes management team. Her efforts to improve the care of hospitalized patients with diabetes have earned her recognition with the “Code Insulin” award from both residents and Insulindependence.
Beyond her clinical roles, Dr. Cho has held leadership positions such as the past VCMC Chief of Staff and Commissioner for the Gold Coast Health Plan.
Dr. Loretta Denering
Interim Director of Ventura County Behavioral Health
Loretta L. Denering, DrPH, MS currently serves as the board-appointed Interim Director for Ventura County Behavioral Health (VCBH), a Department of the Ventura County Health Care Agency. Dr. Denering oversees an array of mental health and substance use disorder programs and services including County-operated adult, perinatal, and youth treatment services, prevention and outreach services, and managed care functions under the County Behavioral Health Plan (BHP). Dr. Denering also directs the implementation of the multi-year California Innovating and Advancing Medi-Cal (CalAIM) initiative including behavioral health payment reform and administrative behavioral health integration and the implementation of behavioral health system reform under the recently passed Proposition 1 –Behavioral Health Services Act (BHSA). Prior to this appointment, Dr. Denering served in roles as the VCBH Assistant Director and the Substance Use Services Division Chief.
She has also held various management and technical positions within the Los Angeles County Department of Public Health. Dr. Denering also spent eight years at the UCLA Semel Institute for Neuroscience and Human Behavior as a Biobehavioral Scientist where she served as the Project Director for the Los Angeles County Evaluation System. She has more than 18 years of experience in the research, evaluation, and administration of public health and behavioral health programs.
Dr. Denering received her doctorate in Public Health, with a focus in Health Promotion and Education and Evaluation and Measurement, from Loma Linda University School of Public Health. She also holds a Master of Science in Clinical Psychology from California Lutheran University and a Bachelor of Arts in Psychology with a minor in Latin American Studies from UCLA.
Rigoberto Vargas
Director of Public Health
Rigoberto Vargas joined the Ventura County Health Care Agency in 1998 and has since held various positions in the Public Health department. In 2013, he was appointed as the Director of the department.
Before joining the agency, Vargas worked with a community-based organization (CBO) and a health maintenance organization (HMO), where he played a significant role in developing and implementing community health promotion programs.
As the Director, Vargas is responsible for overseeing numerous wellness and disease prevention programs within the Ventura County Public Health (VCPH) department. Under his leadership, VCPH has received multiple grants from local, state, and federal sources.
In June 2014, VCPH achieved national accreditation from the Public Health Accreditation Board (PHAB). This milestone made VCPH the first public health department in California and one of the first 50 in the nation to attain this significant recognition.
Dee Pupa
Director and CEO of the Ventura County Health Care Plan
Dee Pupa joined the County of Ventura in early 2002 and has dedicated nearly two decades to serving in a comprehensive role. Throughout her tenure, Pupa has played a crucial part in achieving several significant milestones for the Agency.
Some of these milestones include the successful implementation and structuring of the Health Care Coverage Initiative (HCCI) and Low-Income Health Program (LIHP), the establishment of the County Organized Health System (COHS) or Gold Coast Health Plan, and the seamless transition of 25,000 Healthy Families and LIHP beneficiaries to Managed Medi-Cal.
Pupa also played a pivotal role in facilitating the healthcare reform and ensuring Ventura County Health Care Plan’s (VCHCP) selection as one of only 13 plans approved for participation in Covered California across the entire State of California. Moreover, VCHCP received full accreditation from the National Committee for Quality Assurance.
Beyond her contributions to VCHCP, Pupa serves as a longtime Commissioner for the Gold Coast Health Plan and currently holds the position of Chair.
Jessica Ruiz
Director of Human Resources
Jessica Ruiz has been a dedicated member of the County of Ventura CEO-HR group since 2013, bringing over 16 years of valuable experience in Human Resources, including an extensive background in both the private and public sectors.
Ruiz is an alumna of California Baptist University, where she earned both a bachelor’s and a master’s degree in Business Administration.
Additionally, she is a graduate of the County of Ventura Leadership and Excellence (LEAP) Program and the Ventura County Leadership Academy, highlighting her commitment to professional development and leadership within the organization.
