Our Team

Gregory Burt, MD

Portrait of Dr. BurtGregory Burt, M.D., specializes in Internal Medicine and brings 20 years of experience as a Board Certified Internist to his patients at Adventist Health Physicians Network Family Physicians. Since completing medical school at Tulane University in New Orleans, Dr. Burt has become well acquainted with the issues facing residents of northern California by serving patients in Colusa, Vacaville, Sacramento and Davis. His approach to medicine is patient-centered, built on caring for the individual over many years in context of their family, with a focus on food and lifestyle.

Outside of the office, Dr. Burt enjoys cooking, Crossfit, time with family and friends and travel.


Mutuhi S. Mugo, MD

Portrait of Dr. MugoDr. Mugo received her BS degree from the University of Massachusetts Amherst. She attended the University of Southern California, Keck School of Medicine, where she received her Doctorate of Medicine and completed her Internship and Residency. She is Board Certified in Internal Medicine and has a special interest in preventive health care, as well as public health care. Dr. Mugo practiced medicine in Yuba and Sutter Counties for two years before joining Adventist Health and Rideout Clinic.


Mark Sawyer, MD

Portrait of Dr. SawyerMark Sawyer, M.D., is a pediatrician who joins Adventist Health Physicians Network Family Physicians moving from the East Coast. A Yuba City native, he completed medical school at Case Western Reserve University and a pediatric residency at the Children’s Hospital of Philadelphia. He has a special interest in early childhood literacy, and has published multiple journal articles and developed a mobile app on the topic. Outside of medicine, Dr. Sawyer’s experience with children includes professional work as a preschool teacher in Korea and more than 10 years of school-based volunteer activities.

Dr. Sawyer enjoys photography, electronics, singing/guitar, and spending time with family. He speaks Korean and English.


John G. McAvoy, PA-C

Portrait of Dr. McAvoyJohn graduated from the college of Osteopathic Medicine of the Pacific Physician Assistant program in 1994 in Southern California and then moved to this area to begin practice. He has a BA in psychology from the University of La Verne and worked in the past as a Psychiatric Technician. He loves working in family practice because of the variety it presents. He enjoys music, cooking, and gardening.


Christopher Pacheco, PA-C

Christopher PachecoChristopher Pacheco, PA-C, provides primary healthcare for the entire family. His clinical experience includes family medicine, cardiology, emergency medicine and internal medicine. He has managed chronic diseases such as hypertension, diabetes and rheumatoid arthritis.