ABOUT
OUR TEAM
Tarah Nixon, BS, CVT,
dip. ABST, CCAT
Elite Fear Free Certified
Low Stress Handling Silver Certified
Tarah is a Certified Veterinary Technician with over 25 years of experience in the veterinary field. She earned her Bachelor of Science in Animal Science from the University of Arizona in 2004, and later returned to school to complete a Master's-level diplomate in Animal Behavior (Dip. ABST) in 2020. Most recently, Tarah became a Certified Companion Animal Rehabilitation Therapist (CCAT, 2025), expanding her expertise into rehabilitation care.
Throughout her career, Tarah has worked across nearly every corner of veterinary medicine — from emergency and critical care, to technician supervisor at a large specialty hospital, to practice manager in general practice, to educator training the next generation of veterinary technicians. That breadth gives the AVA team a rare, well-rounded perspective on how animals move through the healthcare system, and what they need at every stage.
Tarah is an Elite Fear Free Certified Professional and a passionate advocate for the Fear Free philosophy — so much so that she built it into the curriculum during her time as an instructor in an associate degree program for veterinary technician students. She has also completed the Low Stress Handling Silver Certification Program, deepening her ability to read the subtle ways dogs and cats communicate fear and anxiety, and to handle them in a way that keeps them calm and comfortable.
Tarah's connection to animals started early: she's been training and showing dogs and horses since she was 6 years old — a lifelong passion that continues to shape the compassionate, low-stress care she brings to every patient.
Lisa Wirth, BS, VMD, CCAT
Veterinarian and Owner
Elite Fear Free Certified
PennHIP Certified
Dr. Wirth has a Bachelor’s of Science in Veterinary Science from the University of Arizona (2005). She returned to her birth state of Pennsylvania to attend the University of Pennsylvania School of Veterinary Medicine, earning her Veterinary Medicine Doctorate (2011). She became a Certified Companion Animal Rehabilitation Therapist through the North Carolina State Veterinary Medicine program (2025).
Dr. Wirth has experience in general and emergency veterinary medicine; she has edited and illustrated for veterinary journals and conference proceedings; and she was also staff veterinarian and an instructor in an associate degree program for veterinary technician students.
Fear Free methods of working with your pets are incredibly important to Dr. Wirth. She became certified the first year Fear Free was offered and is Elite Fear Free certified.
Dr. Wirth decided when she was five-years-old that she was going to be a veterinarian, and clearly, her early childhood dream did not waver! She enjoys spending her free time with her husband of 20+ years, three children, and three dogs.
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Diana Garcia, AS, CVT
Elite Fear Free Certified
Diana is a graduate of Pima Medical Institute's Veterinary Technology Program, where she received her Associate's Degree in 2017. She then passed her national and Arizona state board exams, becoming a Certified Veterinary Technician.
Shortly after graduating, she gained two years experience working in a veterinary emergency intensive care unit. Diana also has experience working in a busy general practice.
Diana is a Fear Free Certified Professional and is now working toward her Elite Certification. Diana believes strongly in using the techniques learned in Fear Free training to make veterinary visits as low stress as possible for pets.
In her free time, Diana dances with a local group in a variety of styles, including Mexican folklore. She also loves to travel and spend time with family and friends.
Born and raised in Tucson, Arizona, Diana has always been passionate about caring for animals. She has two dogs, Luna and Shay, and four cats, Anchovie, Simon, Blue, and Echo.
