Delma J. Nieves, MD

Fellowship Program Director
Professor of Pediatrics

Delma Nieves’ publications and research interests include pertussis, leptospirosis, invasive fungal infections, invasive pneumococcal diseases and infections of the neonate. She graduated from UW School of Medicine, then went on to do a pediatric residency at CHOC and a pediatric infectious disease fellowship at Mattel Children’s Hospital/University of California, Los Angeles.

Antonio C. Arrieta, MD

Professor of Pediatrics
Division Chief for CHOC Pediatric Infectious Diseases

Antonio Arrieta's publications and research interests include pharmacokinetic/pharmacodynamic (PK/PD) studies, invasive fungal infections and antifungal therapy, invasive pneumococcal diseases, empyema in children and infections of the neonate. Dr. Arrieta graduated from Universidad Peruana Cayetano, then completed a pediatric residency at Southern Illinois University and a pediatric infectious disease fellowship at Memorial Miller Children’s Hospital/UCI.

Negar Ashouri, MD

Assistant Professor of Pediatrics
Director of Antimicrobial Stewardship at CHOC

Negar Ashouri's publications and research interests include Kawasaki disease and congenital cytomegalovirus disease. Dr. Ashouri graduated from St. George’s University School of Medicine, followed by a pediatric residency at CHOC and a pediatric infectious disease fellowship at Children’s Hospital of Los Angeles.

Michele Cheung, MD, MPH

Volunteer Assistant Professor of Pediatrics
Medical Officer of Community & Nursing Services, Orange County Health Care Agency

Michele Cheung's publications and research interests include methicillin-resistant Staphylococcus aureus (MRSA) infections, invasive pneumococcal disease and public health emergency preparedness. Dr. Cheung graduated from Jefferson Medical College, then did a pediatric residency at UCI and a pediatric infectious disease fellowship at University of California, San Francisco.
 

Jasjit Singh, MD

Associate Professor of Pediatrics 
Director of Infection Prevention and Epidemiology at CHOC

Jasjit Singh’s publications and research interests include vaccine-preventable diseases, vaccine efficacy, tuberculosis, drug-resistant organisms and outbreak management. Dr. Singh graduated from Duke University School of Medicine and then completed a pediatric residency at New York Hospital-Cornell Medical Center and a pediatric infectious disease fellowship at Johns Hopkins University Hospital.

Aaron Shaw, MD

Professor of Pediatrics

Aaron Shaw is the newest CHOC clinical faculty member to join our program. Dr. Shaw’s publications and research interests include cervical lymphadenitis and deep neck space infections. He graduated from the University of Tennessee Health Science Center, then completed a pediatric residency at the University of Tennessee Health Science Center and a pediatric infectious disease fellowship at Children’s Mercy Hospital.

E.R Chulie Ulloa, MD, MsC

Assistant Professor of Pediatrics

E.R. Chulie Ulloa’s publications and research interests include novel therapies for drug-resistant or difficult-to-treat bacterial infections. Dr. Ulloa graduated from Stanford University School of Medicine, then completed a pediatric residency at Boston Children’s Hospital Harvard Medical School and a pediatric infectious disease fellowship at Children’s Hospital of Philadelphia.

Matthew Zahn, MD

Volunteer Assistant Clinical Professor of Pediatrics
Medical Director of the Division of Epidemiology & Assessment, Orange County Health Care Agency

Matthew Zahn's publications and research interests include measles epidemiology, meningococcal disease outbreaks, drug-resistant organisms and vaccines. Dr. Zahn graduated from St. Louis University School of Medicine, then did a pediatric residency at Cardinal Glennon Children’s Hospital and a pediatric infectious disease fellowship at Children’s Hospital of Denver.