Faculty bio page2
David H. Walker, MD

David H. Walker, MDProfessor

Department of Pathology
The Carmage and Martha Walls Distinguished University Chair in Tropical Diseases
Executive Director, UTMB Center for Biodefense and Emerging Infectious Disease
Autopsy Attending Pathologist

Phone: (409) 747-3990
Email: dwalker@utmb.edu

David H. Walker, MD

Dr. Walker's research interests are broadly in the area of obligately intracellular bacteria that are transmitted by arthropod vectors focused on immune mechanisms against rickettsiae, ehrlichiae and Orientia tsutsugamushi and identification of the protein antigens that stimulate immunity. Although the diseases caused by rickettsiae include many long known and feared life threatening infections such as Rocky Mountain spotted fever and epidemic typhus, elucidation of their molecular composition and effector immune mechanisms remains productive lines of investigation. In contrast, human ehrlichioses are truly emerging infectious diseases that are causing increasingly prevalent, severe infections. Ehrlichial pathogenesis and immunity are in the process of being discovered and investigated at present for these novel organisms. His focus has also added the neglected tropical rickettsial disease, scrub typhus.

His investigative armamentarium includes outstanding mouse models of spotted fever and typhus rickettsioses, monocytotropic ehrlichioses, and scrub typhus which lend themselves to the study of pathogenesis as well as immunity. Other projects include development of vaccines against Rickettsia rickettsii, R. prowazekii, E. canis, E. chaffeensis, and O. tsutsugamushi, development of new diagnostic tests utilizing patented intellectual property sponsored by the Clayton Foundation, and international collaborations in Mexico and Colombia with opportunities for field and laboratory work in tropical locations.

His research is greatly enhanced by collaborative efforts involving the molecular expertise of Drs. Jere McBride and Donald Bouyer, immunologic knowledge and skills of Dr. Rong Fang, the ultrastructural expertise of Dr. Vsevolod Popov, and the vector biology skills of Dr. Tais Saito. New initiatives include vector biology of tick-borne ehrlichial and rickettsial infections.

BA Davidson College, Davidson, North Carolina History (Valedictorian) 1965
MD Vanderbilt University, School of Medicine, Nashville, Tennessee   1969
PGY-1 to PGY-4 Peter Bent Brigham Hospital, Boston, Massachusett Pathology 1973
Research Gorgas Memorial Laboratory, Panama City, Republic of Panama Tropical Pathology 1971
Chief Resident Peter Bent Brigham Hospital, Boston, Massachusetts Pathology 1971
Research Fellow Harvard University, School of Medicine, Boston, Massachusetts Pathology 1972
Clinical Fellow Harvard University, School of Medicine, Boston, Massachusetts Pathology 1973
2016 Fellow, American Academy of Microbiology
2015 Fellow, American Society of Tropical Medicine and Hygiene
2012  Distinguished Medical Alumnus, Vanderbilt University
2001-2020 America's Top Doctors
2010 John J. Andujar Citation of Merit, Texas Society of Pathologists
2007 University of Texas System Star Faculty Award
2007 Distinguished Faculty Research Award
Graduate School of Biomedical Sciences,University of Texas Medical Branch, Galveston, Texas
2006 Harlan J. Spjut Award
Houston Society of Clinical Pathologists
2002 Alpha Omega Alpha
1997 Mustard Seed Award in Research
Sealy Society, University of Texas Medical Branch, Galveston, Texas
1996 Docteur Honoris Causa
Universite de la Mediterranee, Marseille, France
1965-1969 Justin Potter Merit Scholarship
Vanderbilt University, School of Medicine, Nashville, Tennessee
1963 Phi Beta Kappa

Appointments
2002-Present Director UTMB Center for Biodefense and Emerging Infectious Disease
University of Texas Medical Branch, Galveston, Texas
1994-2010 Director WHO Collaborating Center for Tropical Diseases
University of Texas Medical Branch, Galveston, Texas
1991-Present Member Graduate School of Biomedical Sciences
University of Texas Medical Branch, Galveston, Texas
1987-Present Autopsy Attending Pathologist Department of Pathology
University of Texas Medical Branch, Galveston, Texas
1987-Present Professor Department of Pathology
University of Texas Medical Branch, Galveston, Texas
1987-2014 Professor and Chairman Department of Pathology
University of Texas Medical Branch, Galveston, Texas

   * - Denotes election

2008 The American Association of Immunologists
1996 Texas Society of Pathology
1991 Texas Branch, American Society for Microbiology
1989 Texas Society of Pathologists, Inc.*
1989 American Society of Clinical Pathologists, Inc.*
1988 American Association for the Advancement of Science
1988 Association of Pathology Chairmen, Inc.
1988 Houston Society of Clinical Pathologists
1988 Galveston County Medical Society*
1988 Texas Medical Association (H5380)*
1988 College of American Pathologists* Fellow

1988

Binford-Dammin Society of Infectious Disease Pathologists
President-elect, 1988-89; President, 1989-90; Secretary-Treasurer,1995-2001
1987 Sigma Xi, The Scientific Research Society
1984 American Society of Tropical Medicine and Hygiene
Nominating Committee, 1996-1998, Chair 1998
1981 Infectious Diseases Society of America Fellow*
1979 American Society of Rickettsiology
Vice President, 1988-89; President, 1989-91
1977 American Society for Investigative Pathology
1975 United States-Canadian Division of the International Academy of Pathology
Council Member 1996-2000
1975 American Society for Microbiology

Peer-reviewed Aritcles:

    1. Fang R, Ismail N, WALKER DH. Contribution of NK cells to the innate phase of host protection against an intracellular bacterium targeting systemic endothelium. Am J Pathol. 2012 Jul;181(1):185-95. PMCID: PMC3388147.
    2. Shelite TR, Saito TB, Mendell NL, Gong B, Xu G, Soong L, Valbuena G, Bouyer DH, WALKER DH. A hematogenously disseminated Orientia tsutsugamushi-infected murine model of scrub typhus. PloS Negl Trop Dis. 2014 Jul;8(7):e2966. PMCID: PMC4091938.
    3. Blanton LS, Mendell NL, WALKER DH, Bouyer DH. Rickettsia amblyommii induces cross protection against lethal Rocky Mountain spotted fever in a guinea pig model. Vector Borne Zoonotic Dis. 2014 Aug;14(8):557-62. Research Support, Non-U.S. Gov’t.
    4. Soong L, Wang H, Shelite TR, Mendell NL, Sun J, Gong B, Valbuena G, Bouyer DH, WALKER DH. Strong type 1, but impaired type 2, immune responses contribute to Orientia tsutsugamushi induced pathology in mice. PLoS Negl Trop Dis. 2014 Sep;8(9):e3191. PMCID: PMC4177881.
    5. Saito TB, Thirumalapura NR, Shelite TR, Rockx-Brouwer D, Popov VL, WALKER DH. An animal model of a newly emerging human ehrlichiosis. J Infect Dis. 2015 Feb;211(3):452-61. PMCID: PMC4351372.
    6. Blanton LS, Vohra RF, Bouyer DH, WALKER DH. Reemergence of murine typhus in Galveston, Texas, USA, 2013. Emerg Infect Dis. 2015 Mar;21(3):484-6. PMCID: PMC4344263.
    7. Saito TB, WALKER DH. A tick vector transmission model of monocytotropic ehrlichiosis. J Infect Dis. 2015 Sep;212(6):968-77. PMCID: PMC4548458.
    8. Blanton LS,Idowu BM,Tatsch TN,Henderson JM,Bouyer DH,WALKER DH. Opossumsandcat fleas: New insights in the ecology of murine typhus in Galveston, Texas. Am J Trop Med Hyg. 2016 Aug;95(2):457-61. PMCID: PMC4973200.
    9. Mendell NL, Bouyer DH, WALKER DH. Murine models of scrub typhus associated with host control of Orientia tsutsugamushi infection. PLoS Negl Trop Dis. 2017 Mar;11(3):e0005453. PMCID: PMC5362142.
    10. Xu G, Mendell NL, Liang Y, Shelite TR, Goez-Rivillas Y, Soong L, Bouyer DH, WALKER DH. CD8+ T cells provide immune protection against murine disseminated endotheliotropic Orientia tsutsugamushi infection. PLoS Negl Trop Dis. 2017 Jul;11(7):e0005763. PMCID: PMC5536391.
    11. Saito TB, Bechelli J, Smalley C, Karim S, WALKER DH. Vector tick transmission model of spotted fever rickettsiosis. Am J Pathol. 2019 Jan;189(1):115-123. doi: 10.1016/j.ajpath.2018.09.005. PMCID: PMC6593257.

Reviews:

    1. WALKER DH, Dumler JS. The role of CD8 T lymphocytes in rickettsial infections. Semin Immunopathol. 2015 May;37(3):289-99. PMCID: PMC4458380.
    2. Fang R, Blanton LS, WALKER DH. Rickettsiae as emerging infectious agents. Clin Lab Med. 2017 Jun;37(2):383-400. Review.
    3. Xu G, Walker DH, Jupiter D, Melby PC, Arcari CM. A review of the global epidemiology of scrub typhus. PLoS Negl Trop Dis. 2017 Nov 3;11(11):e0006062. PMCID: PMC5687757.
    4. Sahni A, Fang R, Sahni SK, WALKER DH. Pathogenesis of rickettsial diseases: Pathogenic and immune mechanisms of an endotheliotropic infection. Annu Rev Pathol. 2019 Jan 24;14:127-152. Review. PMCID: PMC6505701.

Books:

    1. Guerrant RL, WALKER DH, Weller PF. 2011. Tropical Infectious Diseases: Principles, Pathogens, and Practice. 3rd Ed Philadelphia (PA): Elsevier Churchill, Livingstone.

NIH Biosketch