Tracy H. Hazen, PhD

I received a Ph.D. in Applied Biology specializing in Microbiology from the Georgia Institute of Technology. During my Ph.D. I studied microbial ecology and the contribution of plasmids and phages to the genetic diversity of bacteria in coastal marine environments. I also used molecular methods to compare the genetic diversity of Vibrio parahaemolyticus isolated from clinical and environmental specimens. I completed my postdoctoral training in the laboratory of Dr. David Rasko at the Institute for Genome Sciences and then joined the faculty of the Department of Microbiology and Immunology and the Institute for Genome Sciences.

Since joining IGS I have used comparative genomics and transcriptomics to investigate the diversity of enteric and nosocomial pathogens. While I have studied numerous diverse microorganisms, the majority of my work has focused on E. coli associated with childhood diarrhea, or multidrug resistant nosocomial pathogens from patients in intensive care units. I have also carried forward my interest in plasmids from my graduate studies and have described the genetic diversity of virulence plasmids from E. coli as well as antibiotic resistance plasmids from E. coli and additional species including Klebsiella. My current research examines the genetic diversity of antibiotic resistant pathogens and I am interested in translational applications of sequencing-based microbial surveillance in healthcare settings for early outbreak detection and infection control.

E. coli, Klebsiella, Acinetobacter, genomics, evolution, antibiotic resistance, microbial surveillance

1. Hazen, T.H., J.W. Sahl, M.S. Donnenberg, C.M. Fraser, F. Scheutz, and D.A. Rasko.  2013.  Refining the pathovar paradigm via phylogenomics of the attaching and effacing Escherichia coli.  Proc. Natl. Acad. Sci. USA, 110:12810-12815. (PMID: 23858472)
2. Subashchandrabose, S., T.H. Hazen, A.R. Brumbaugh, S.D. Himpsl, S.N. Smith, R.D. Ernst, D.A. Rasko, and H. Mobley.  2014.  Human-specific induction of Escherichia coli fitness genes during clinical urinary tract infection.  Proc. Natl. Acad. Sci. USA 111: 18327-32. (PMID: 25489107)
3. Hazen, T.H., L. Zhao, M.A. Boutin, G. Robinson, A.D. Harris, D.A. Rasko, and J.K. Johnson.  2014.  Comparative genomics of an IncA/C multidrug resistance plasmid from Escherichia coli and Klebsiella species isolated from ICU patients: the utility of whole genome sequencing in healthcare settings.  Antimicrob. Agents Chemother. 58: 4814-4825. (PMID: 24914121)
4. Hazen, T.H., J.B. Kaper, J.P. Nataro, and D.A. Rasko.  2015.  Comparative genomics provides insight into the diversity of the attaching and effacing Escherichia coli (AEEC) virulence plasmids. Infect. Immun. 83:4103-4117. (PMID: 26238712)
5. Hazen, T.H., M.S. Donnenberg,S. Panchalingam, M. Antonio, A. Hossain, I. Mandomando, J.B. Ochieng, T. Ramamurthy, B. Tamboura, S. Qureshi, F. Quadri, A. Zaidi, K.L. Kotloff, M.M. Levine, E.M. Barry, J.B. Kaper, D.A. Rasko, and J.P. Nataro.  2016.  Genomic diversity of EPEC associated with clinical presentations of differing severity.  Nat. Microbiol. (PMID: 27571975)
6. Hazen, T.H.,C. Daugherty, A.C. Shetty, A.A. Mahurkar, O.R. White, J.P. Nataro, J.B. Kaper, and D.A. Rasko. 2017.  Transcriptional variation of diverse enteropathogenic Escherichia coli under virulence-inducing conditions. mSystems, (PMID: 28766584).
7. Hazen, T.H., Michalski, Q. Luo, A.C. Shetty, S.C. Daugherty, J. Fleckenstein, and D.A. Rasko. 2017.  Comparative genomics and transcriptomics of hybrid Escherichia coli isolates carrying virulence factors of both enteropathogenic and enterotoxigenic E. coli.  Sci. Reports, (PMID: 28615618).
8. Richter, T., H. Hazen, D. Lam, C.L. Coles, J.C. Seidman, Y. You, E.K. Silbergeld, C.M. Fraser, and D.A. Rasko. 2018. Dynamics of Escherichia coli in human populations in Tanzania. mSphere. (PMID: 30404930)
9. Hazen, T.H., and D.A. Rasko. 2019. Complete genome of the atypical enteropathogenic Escherichia coli archetype isolate E110019 highlights a role of plasmids in dissemination of the type III secreted effector EspT. Infect. Immun. (PMID: 31358567)
10. Hazen, T.H., S. Nagaraj, E.M. Barry, J. Bitoun, W.H. Chen, S.M. Tennant, and D.A. Rasko. 2019. Comparative genomics of CFA/I and CS6-producing ST-only enterotoxigenic Escherichia coli
    associated with human diarrhea. mSystems. (PMID: 30944874)