Theodore Robertson Pak

Assistant Professor, Infectious Diseases
School of Medicine

Medical Director, Epidemiology and Infection Prevention, UCI Health-Irvine

Lab Website - tpaklab.org

2019-2021 Residency in Internal Medicine, Massachusetts General Hospital
2021-2024 Fellowship in Infectious Diseases, Mass General Brigham
2022-2024 Research Fellow, Department of Population Medicine, Harvard Medical School

2016 Medical Scholars Program Award, Infectious Diseases Society of America
2016 Sanfurd G. Bluestein Endowed Scholarship, Icahn School of Medicine at Mount Sinai
2017 Mount Sinai Trainee Innovation Idea Award, Icahn School of Medicine at Mount Sinai
2018 Jonathan Epstein Scholar, Interurban Clinical Club
2024 Emerging-Generation Award, The American Society for Clinical Investigation
2024 Top Featured Oral Abstract, The Society for Healthcare Epidemiology of America
2024 Assembly on Critical Care 2024 Abstract Scholarship, American Thoracic Society
2024 Information Technology in Medicine Award, Massachusetts Medical Society
2025 Maxwell Finland Research Award, Massachusetts Infectious Diseases Society

Pak TR, Kanjilal S, McKenna CS, Hoffner-Heinike A, Rhee C, Klompas M. Syndromic analysis of sepsis cohorts using large language models. JAMA Netw Open. 2025;8(10):e2539267.

Klompas M, Pak TR, Rhee C. Protecting patients and peers from healthcare personnel with respiratory viral infections. Infect Control Hosp Epidemiol. 2025 Jan 27:1-3.

Kondo Y, Klompas M, McKenna CS, Pak TR, Shappell CN, DelloStritto L, Rhee C. Association Between the Sequence of ß-lactam and Vancomycin Administration and Mortality in Patients with Suspected Sepsis. Clin Infect Dis. 2024 Dec 5:ciae599.

Pak TR, Sánchez SM, McKenna CS, Rhee C, Klompas M. Assessment of racial, ethnic, and sex-based disparities in time-to-antibiotics and sepsis outcomes in a large multi-hospital cohort. Crit Care Med. 2024 Dec 1;52(12):1928-1933.

Pak TR, Chen T, Kanjilal S, McKenna CS, Rhee C, Klompas M. Testing and masking policies and hospital-onset respiratory viral infections. JAMA Netw Open. 2024 Nov 4;7(11):e2448063.

Klompas M, McKenna CS, Kanjilal S, Pak TR, Rhee C, Chen T. Morbidity and mortality of hospital-onset SARS-CoV-2 due to Omicron versus prior variants: a propensity-matched analysis. Ann Intern Med. 2024 Aug;177(8):1078-1088.

Pak TR, Young J, McKenna CS, Agan A, DelloStritto L, Filbin MR, Dutta S, Kadri SS, Septimus EJ, Rhee C*, Klompas M*. Risk of Misleading Conclusions in Observational Studies of Time-to-Antibiotics and Mortality in Suspected Sepsis. Clin Infect Dis. 2023 Nov 30;77(11):1534-1543.

Rhee C, Klompas M, Pak TR, Köhler JR. In Support of Universal Admission Testing for SARS-CoV-2 During Significant Community Transmission. Clin Infect Dis. 2024 Feb 17;78(2):439-444.

Pak TR, Rhee C, Wang R, Klompas M. Discontinuation of Universal Admission Testing for SARS-CoV-2 and Hospital-Onset COVID-19 Infections in England and Scotland. JAMA Intern Med. 2023 Aug 1;183(8):877-880.

Pak TR, Rhee C, Klompas M. Timing and Spectrum of Antibiotic Treatment for Suspected Sepsis and Septic Shock: Why so Controversial? Infect Dis Clin North Am. 2022 Dec;36(4):719-733

Javaid W*, Ehni J*, Gonzalez-Reiche AS*, Carreño JM, Hirsch E, Tan J, Khan Z, Kriti D, Ly T, Kranitzky B, Barnett B, Cera F, Prespa L, Moss M, Albrecht RA, Mustafa A, Herbison I, Hernandez MM, Pak TR, Alshammary HA, Sebra R, Smith ML, Krammer F, Gitman MR, Sordillo EM, Simon V, van Bakel H. Real-Time Investigation of a Large Nosocomial Influenza A Outbreak Informed by Genomic Epidemiology. Clin Infect Dis. 2021 Dec 6;73(11):e4375-e4383.

Berbel Caban A*, Pak TR*, Obla A, Dupper AC, Chacko KI, Fox L, Mills A, Ciferri B, Oussenko I, Beckford C, Chung M, Sebra R, Smith M, Conolly S, Patel G, Kasarskis A, Sullivan MJ, Altman DR, van Bakel H. PathoSPOT genomic epidemiology reveals under-the-radar nosocomial outbreaks. Genome Med. 2020 Nov 16;12(1):96.

Oliveira PH, Ribis JW, Garrett EM, Trzilova D, Kim A, Sekulovic O, Mead EA, Pak TR, Zhu S, Deikus G, Touchon M, Lewis-Sandari M, Beckford C, Zeitouni NE, Altman DR, Webster E, Oussenko I, Bunyavanich S, Aggarwal AK, Bashir A, Patel G, Wallach F, Hamula C, Huprikar S, Schadt EE, Sebra R, van Bakel H, Kasarskis A, Tamayo R, Shen A*, Fang G*. Epigenomic characterization of Clostridioides difficile finds a conserved DNA methyltransferase that mediates sporulation and pathogenesis. Nat Microbiol. 2020 Jan;5(1):166-180.

Sullivan MJ, Altman DR, Chacko KI, Ciferri B, Webster E, Pak TR, Deikus G, Lewis-Sandari M, Khan Z, Beckford C, Rendo A, Samaroo F, Sebra R, Karam-Howlin R, Dingle T, Hamula C, Bashir A, Schadt E, Patel G, Wallach F, Kasarskis A, Gibbs K, van Bakel H. A Complete Genome Screening Program of Clinical Methicillin-Resistant Staphylococcus aureus Isolates Identifies the Origin and Progression of a Neonatal Intensive Care Unit Outbreak. J Clin Microbiol. 2019 Dec;57(12)

Altman DR, Sullivan MJ, Chacko KI, Balasubramanian D, Pak TR, Sause WE, Kumar K, Sebra R, Deikus G, Attie O, Rose H, Lewis M, Fulmer Y, Bashir A, Kasarskis A, Schadt EE, Richardson AR, Torres VJ, Shopsin B, van Bakel H. Genome Plasticity of agr-Defective Staphylococcus aureus during Clinical Infection. Infect Immun. 2018 Oct;86(10).

Michlmayr D*, Pak TR*, Rahman AH, Amir ED, Kim EY, Kim-Schulze S, Suprun M, Stewart MG, Thomas GP, Balmaseda A, Wang L, Zhu J, Suaréz-Fariñas M, Wolinsky SM, Kasarskis A, Harris E. Comprehensive innate immune profiling of chikungunya virus infection in pediatric cases. Mol Syst Biol. 2018 Aug 27;14(8):e7862.

Chacko KI, Sullivan MJ, Beckford C, Altman DR, Ciferri B, Pak TR, Sebra R, Kasarskis A, Hamula CL, van Bakel H. Genetic Basis of Emerging Vancomycin, Linezolid, and Daptomycin Heteroresistance in a Case of Persistent Enterococcus faecium Bacteremia. Antimicrob Agents Chemother. 2018 Apr;62(4).

Pak TR, Chacko KI, O'Donnell T, Huprikar SS, van Bakel H, Kasarskis A, Scott ER. Estimating Local Costs Associated With Clostridium difficile Infection Using Machine Learning and Electronic Medical Records. Infect Control Hosp Epidemiol. 2017 Dec;38(12):1478-1486.

Hamlin RE, Rahman A, Pak TR, Maringer K, Mena I, Bernal-Rubio D, Potla U, Maestre AM, Fredericks AC, Amir ED, Kasarskis A, Ramos I, Merad M, Fernandez-Sesma A. High-dimensional CyTOF analysis of dengue virus-infected human DCs reveals distinct viral signatures. JCI Insight. 2017 Jul 6;2(13).

Bashir A, Attie O, Sullivan M, Sebra R, Singh KV, Altman D, Pak TR, Dutta J, Chacko K, Webster E, Lewis M, Hamula C, Delli Carpini KW, Murray BE, Kasarskis A, van Bakel H, Huprikar S. Genomic confirmation of vancomycin-resistant Enterococcus transmission from deceased donor to liver transplant recipient. PLoS One. 2017;12(3):e0170449.

Pak TR, Kasarskis A. How next-generation sequencing and multiscale data analysis will transform infectious disease management. Clin Infect Dis. 2015 Dec 1;61(11):1695-702.

Pak TR, Altman DR, Attie O, Sebra R, Hamula CL, Lewis M, Deikus G, Newman LC, Fang G, Hand J, Patel G, Wallach F, Schadt EE, Huprikar S, van Bakel H, Kasarskis A, Bashir A. Whole-genome sequencing identifies emergence of a quinolone resistance mutation in a case of Stenotrophomonas maltophilia bacteremia. Antimicrob Agents Chemother. 2015 Nov;59(11):7117-20.

Finkelstein M, Siddiqui A, Pak TR, Hu K, Ciccariello C, Knabben V, Chiang D, Thomas DC, Meah YS. A user-editable web-based platform to streamline clinical information flow. Stud Health Technol Inform. 2015;210:909-13.

Pak TR, Roth FP. ChromoZoom: a flexible, fluid, web-based genome browser. Bioinformatics. 2013 Feb 1;29(3):384-6.

Rozenblatt-Rosen O*, Deo RC*, Padi M*, Adelmant G*, Calderwood MA, Rolland T, Grace M, Dricot A, Askenazi M, Tavares M, Pevzner SJ, Abderazzaq F, Byrdsong D, Carvunis AR, Chen AA, Cheng J, Correll M, Duarte M, Fan C, Feltkamp MC, Ficarro SB, Franchi R, Garg BK, Gulbahce N, Hao T, Holthaus AM, James R, Korkhin A, Litovchick L, Mar JC, Pak TR, Rabello S, Rubio R, Shen Y, Singh S, Spangle JM, Tasan M, Wanamaker S, Webber JT, Roecklein-Canfield J, Johannsen E, Barabási AL, Beroukhim R, Kieff E, Cusick ME, Hill DE, Münger K, Marto JA, Quackenbush J, Roth FP, DeCaprio JA, Vidal M. Interpreting cancer genomes using systematic host network perturbations by tumour virus proteins. Nature. 2012 Jul 26;487(7408):491-5.

Legendre M, Pochet N, Pak TR, Verstrepen KJ. Sequence-based estimation of minisatellite and microsatellite repeat variability. Genome Res. 2007 Dec;17(12):1787-96.

2016–2019 NIH/NIAID Individual NRSA (F30 AI122673) Principal Investigator, “Multiscale analysis of immune profiling data from dengue and chikungunya virus infections in humans”

2024–Curr AHRQ (K08 HS030118) Principal Investigator, "Identifying Sepsis Phenotypes Associated with Antibiotic-Resistant Pathogens Using Large Language Models and Machine Learning"

Infectious Disease (IM)

Internal Medicine

Link to this profile
https://faculty.uci.edu/profile/?facultyId=7325

Last updated
01/15/2026