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Justin R. Ortiz, MD, MS

Academic Title:


Primary Appointment:


Additional Title:

Professor of Medicine


HSF1, 480

Phone (Primary):

(410) 706-6020


(410) 706-3502

Education and Training


Bachelor of Arts in English Literature, Dartmouth College, 1995

Post baccalaureate pre-medical training, Colorado State University, 1996

Doctor of Medicine, University of California San Francisco, School of Medicine, 2002

Master of Science in Epidemiology, University of Washington School of Public Health, 2012

Certificate in Vaccinology, ADVAC Advanced Course of Vaccinology, 2011


Internship and Residency, Categorical Internal Medicine, University of California San Francisco, Department of Medicine, 2005

Epidemic Intelligence Service Officer, Centers for Disease Control and Prevention, Influenza Division, 2007

Pulmonary and Critical Care Medicine Fellowship, University of Washington, Department of Medicine, 2010


Dr. Ortiz is a Professor of Medicine at the UMSOM. He trained as an adult pulmonary and critical care physician and has additional training in field epidemiology and vaccinology. He is an internationally recognized expert in respiratory virus prevention and control. He began his public health research career in 2005 as an Epidemic Intelligence Service (EIS) Officer in the Influenza Division at the US Centers for Disease Control and Prevention (CDC). In this position, he led outbreak investigations for avian influenza in West Africa, designed the global respiratory virus (SARI) surveillance system, and conducted influenza clinical epidemiologic research. After leaving the CDC in 2007, he became faculty at the University of Washington where he led an influenza research group and collaborated on influenza vaccine trials in Senegal, South Africa, and Bangladesh. He was seconded to the World Health Organization (WHO) in Geneva to provide clinical expertise during the 2009 H1N1 influenza pandemic. From 2014-2017, he was a Medical Officer at the WHO Initiative for Vaccine Research where he led influenza vaccine policy, implementation, and research activities. His portfolio also included adult immunization, maternal immunization, and clinical RSV disease. At WHO, he was a member of the Editorial Board for Immunization Position Papers, helping to develop and update institutional policy for numerous vaccines.

Since 2018, he has worked as a physician scientist at the Center for Vaccine Development and Global Health at the University of Maryland. He was the site-Principal Investigator on the Adaptive Covid-19 Treatment Trial (ACTT-1), the first clinical trial to identify an efficacious COVID-19 treatment. He was also a coinvestigator on clinical trials for Moderna and Pfizer COVID-19 vaccines. He is the Co-PI on the NIH-funded Collaborative Influenza Vaccine Innovation Centers (CIVICs) Clinical Core at UMSOM, and he leads CIVICs studies developing controlled human influenza virus infection models to accelerate clinical development of influenza vaccines. He is an advisor to the Council of Medical Specialty Societies on adult immunization, and he co-chairs the American Thoracic Society Vaccine Initiative which aims to improve adult immunization rates among persons with chronic lung disease in the United States.

Research/Clinical Keywords

pneumonia, influenza, respiratory syncytial virus, vaccines, global health

Highlighted Publications

  1. Ortiz JR, Sotomayor V, Uez OC, Oliva O, Bettels D, McCarron M, Bresee JS, Mounts AW. Strategy to enhance influenza surveillance worldwide. Emerg Infect Dis. 2009 Aug;15(8):1271-8.
  2. Ortiz JR, Zhou H, Shay DK, Neuzil KM, Fowlkes AL, Goss CH. Monitoring influenza activity in the United States: a comparison of traditional surveillance systems with Google Flu Trends. PLoS One. 2011 Apr 27;6(4):e18687. PubMed PMID: 21556151; PubMed Central PMCID: PMC3083406.
  3. Madhi SA, Cutland CL, Kuwanda L, Weinberg A, Hugo A, Jones S, Adrian PV, van Niekerk N, Treurnicht F, Ortiz JR, Venter M, Violari A, Neuzil KM, Simões EA, Klugman KP, Nunes MC; Maternal Flu Trial (Matflu) Team. Influenza vaccination of pregnant women and protection of their infants. N Engl J Med. 2014 Sep 4;371(10):918-31. doi: 10.1056/NEJMoa1401480. PubMed PMID: 25184864.
  4. Ortiz JR, Bernstein DI, Hoft DF, Woods CW, McClain MT, Frey SE, Brady RC, Bryant C, Wegel A, Frenck RW, Walter EB, Abate G, Williams SR, Atmar RL, Keitel WA, Rouphael N, Memoli MJ, Makhene MK, Roberts PC, Neuzil KM. A Multicenter, Controlled Human Infection Study of Influenza A(H1N1)pdm09 in Healthy Adults. J Infect Dis. 2023 Aug 11;228(3):287-298. doi: 10.1093/infdis/jiad021. PMID: 36702771; PMCID: PMC10420403.
  5. Fell DB, Azziz-Baumgartner E, Baker MG, Batra M, Beauté J, Beutels P, Bhat N, Bhutta ZA, Cohen C, De Mucio B, Gessner BD, Gravett MG, Katz MA, Knight M, Lee VJ, Loeb M, Luteijn JM, Marshall H, Nair H, Pottie K, Salam RA, Savitz DA, Serruya SJ, Skidmore B, Ortiz JR; WHO taskforce to evaluate influenza data to inform vaccine impact and economic modelling. Influenza epidemiology and immunization during pregnancy: Final report of a World Health Organization working group. Vaccine. 2017 Aug 31. pii: S0264-410X(17)31125-8. doi: 10.1016/j.Vaccine.2017.08.037. [Epub ahead of print] PubMed PMID: 28867508.

Full bibliography on pubmed:

Research Interests

respiratory virus prevention and control

Awards and Affiliations

Early Career Award, Thrasher Research Fund (2009 – 2011)

Harold Amos Medical Faculty Development Award, Robert Wood Johnson Foundation (2010 – 2014)