Our Providers

    John Vaz, MD

    Chief Medical Officer


    Dr. John Vaz  graduated from medical school with honors in 2006. He completed his residency in Internal Medicine from the University of Connecticut and a fellowship in Infectious Disease from the University of Maryland. Having more than 12 years of diverse experiences, especially in Internal Medicine and Infectious Disease, his current practice interests are HIV care, Viral Hepatitis management, PrEP & nPEP, LGBT care including transgender care, and chronic medical illnesses. He is passionate about addressing disparities in health in populations that are served in community health centers.

      Adult Medicine

        Ivy Lou Hibbitt, APRN

        Nurse Practitioner

        Mrs. Ivy Lou Hibbitt, APRN, is a Nurse Practitioner. She graduated in 2015, having over 3 years of diverse experience, especially in Nurse Practitioner. 

            Jason Laird, MD

            Adult Physician


            A graduate of the University of South Carolina School of Medicine Dr. Laird completed  general surgery and internal medicine residency programs at Palmetto Health Richland Memorial Hospital.  He has been certified for Outpatient HIV treatment from the American Academy of HIV Medicine since 2010.  Dr. Laird was Board Certified in Internal Medicine in 2009.  He has been serving our patients since 2015.

                Erik Russell, MD

                Internal Medicine

                Dr. Russell graduated from Eastern Virginia Medical School in 1991 and has been in practice for 27 years. He completed a residency at Franklin Square Hospital Center.

                    Gabrielle O’Sullivan, MD

                    Adult Physician


                    A graduate of the University of Washington in Seattle with a Doctor of Medicine Degree, Dr. O’Sullivan went on to Residency at the University of  California, San Francisco affiliated Sutter Family Practice Residency, Santa Rosa, CA, in 2003. Dr . O’Sullivan was recertified by the American Board of Family Medicine, 11/2013.    She has been serving our patients since 2016

                        Jessica Bullock, APRN

                        Nurse Practitioner Specialist

                        Ms. Jessica Bullock, NP, is a Nurse Practitioner specialist in Wailuku, Hawaii. She graduated in 2014, having over 4 years of diverse experience, especially in Nurse Practitioner. 


                            Aaron Altura, MD

                            OB/Gyn Physician

                            A graduate of UC Davis School of Medicine, Dr. Altura completed his residency in Obstetrics and Gynecology at Louisiana State University in 1995. He has been serving our patients since 1996.

                                Duffy Casey, MD

                                OB/Gyn Physician

                                A graduate of Eastern Virginia Medical School, Dr. Casey completed his     residency in Obstetrics and Gynecology at the University of Hawaii in 2013. Board Certified in Obstetrics and Gynecology since 2013, he has been serving our patients since 2013.

                                    Jaimie Johnson, MD, FACOG

                                    OB/Gyn Physician

                                    A graduate of the University of Florida College of Medicine in Gainesville, Dr. Johnson completed her residency in Obstetrics & Gynecology at the University of Hawaii in 2014. She became board-certified in 2016. She has been serving our patients since 2014.

                                        Michael Aaronoff, MD

                                        OBGYN, FACOG

                                        Dr. Michael Aaronoff, MD is an obstetrics & gynecology specialist and has been practicing for 24 years. He graduated from Emory University School Of Medicine in 1994.


                                            Alison Rivera, MD


                                            Alison Rivera was born and raised in rural southern Illinois. She went to college at the University of Illinois at Urbana Champaign and medical school at Southern Illinois University. Alison completed her pediatrics residency at Louisiana State University in New Orleans and has been board certified in pediatrics since 2015. She has been serving our patients since 2018.

                                                Casandra Simonson, MD


                                                A graduate of University of Kansas School of Medicine, Kansas City, Dr. Simonson attended the Residency program at Louisiana State University Children’s Hospital, New Orleans. Dr. Simonson received her Board certification for Pediatrics in 2014.  She has been serving our patients since 2014.

                                                  Integrated Health

                                                    Daniel Nead, PHD


                                                    Dr. Daniel Nead, PHD, is a Clinical Psychologist. He graduated in 2013, having over 5 years of diverse experience, especially in Health Psychologist.

                                                        Sarah R. Feenstra, DO


                                                        Sarah R. Feenstra, DO is a practicing Psychiatrist (Therapist) in Wailuku, HI. Dr. Feenstra graduated from Lake Erie College of Osteopathic Medicine Erie in 2011 and has been in practice for 7 years. She completed a residency at University of Wisconsin Hospitals & Clinics. Dr. Feenstra is board certified in Psychiatry.

                                                            Helen Barrow, TTS

                                                            A Tobacco Treatment Counselor Certified from the University of Arizona and the Mayo Clinic, Ms. Barrow was named Outstanding Service Provider in Tobacco Control by the Coalition for Tobacco Free Hawaii in 2013.  Currently, she is working on her Master’s of Social Work, a Candidate for graduation summer, 2016.

                                                                Renee Sattler, Nutritionist


                                                                Renee Sattler graduated from University of Houston in 2014, and finished her dietetic internship at Vanderbilt University in 2015.  After serving Pacific Islanders in American Samoa for 2 years, she decided to stay in the islands, and began serving our Maui Ohana in 2018.


                                                                    Emilie Sumida, DDS

                                                                    Emilie Guinto Sumida received her Doctorate of Dental Surgery from the State University of New York at Stony Brook, School of Dental Medicine.  Upon graduation, she was commissioned as a Captain in the United States Army. Her first duty assignment was Schofield Barracks, Hawaii where she completed a two-year Advanced Education in General Dentistry program. After proudly serving in the military as a general dentist for 6 years, she developed her true passion in providing dental care for children while working in underserved areas of Baltimore, Maryland.  In 2015, she fulfilled her dream in becoming a pediatric dentist by completing a post-graduate program in Pediatric Dentistry from the University of Maryland, School of Dental Medicine where she served as chief resident.

                                                                    Dr. Sumida is board certified and a Diplomate of the American Board of Pediatric Dentistry.  She currently works at the Malama I Ke Ola Health Center in Wailuku, Hawaii and is medical staff at Maui Memorial Medical Center where she treats patients under general anesthesia.  She is also full time clinical faculty for NYU Langone Pediatric Dentistry residency program – Hawaii site. Emilie has published in General Dentistry and Pediatric Dentistry.  She is also a member of the American Dental Association, Hawaii Dental Association, Maui County Dental Society, and American Academy of Pediatric Dentistry.

                                                                        Dr Lawrence Shin, DDS

                                                                        Dr Lawrence Shin was born in South Korea and immigrated to Texas when he was 8 years old. He received his bachelor degree of Biomedical Science from Texas A&M then moved to San Antonio and obtained his Doctorate in Dental Surgery from University of Texas Health Science Center at San Antonio.  He chose to practice at Malama I Ke Ola  because they shared a belief in providing community centered, relationship-based,  and comprehensive care that is tailored to fit into the patient’s lives.


                                                                        Dr Shin is currently a member of American Dental Association, the Academy of General Dentistry, Hawaii Dental Association and Fellow of International Congress of Oral Implantologist. He is on track to Fellowship of and Academy of General Dentistry.