A Critical Gap: Investigation of Human Rickettsial Infections in Latin America

  • David H. Walker University of Texas Medical Branch
  • Lucas Scott Blanton University of Texas Medical Branch


The Fifth Latin American Conference on Rickettsial Diseases marks a milestone in the development of rickettsiology in Latin America. The knowledge produced by Latin American rickettsiologists has grown immensely in the last decade. Yet sufficient funding for scientists in rickettsiology has not materialized, as many other scientists and clinicians fail to perceive the importance of rickettsial diseases. To move the field forward, and to gain interest and support from Ministries of Health and funding sources, human studies that establish the incidence and clinical severity of these infections is required. Only studies of human disease can provide these data, which we are unable to determine at present. I propose we close this critical gap by promoting the following:

1. Development of accurate, sensitive, species-specific tests for establishment of the diagnoses of infections caused by Rickettsia, Ehrlichia, and Anaplasma species.

2. Performance of longitudinal, prospective population-based studies of patients utilizing these diagnostic assays to determine the incidence, geographic distribution, seasonality, socioeconomic risk factors, clinical manifestations and severity of illness including mortality.

3. Establishment of knowledge of the human pathophysiology, complications, mechanisms of organ injury, clinical biomarkers of severity and of effective immunity, and mechanisms of protective immunity for rickettsial diseases.

4. Collaboration among scientists investigating human illnesses caused by arboviruses, hantaviruses, leptospirosis, influenza, and other agents of similar syndromes in order to share patient samples, demographic data, and costs and effort of the work.

5. Establishment of human specimen banks for the development of improved diagnostics, investigations of pathogenesis and immunity, and identification of currently unrecognized novel emerging infectious agents.

The critical gap is knowledge of the public health and clinical impact of human infections.  Indeed the ultimate purpose for our investigations of rickettsiae and rickettsial diseases is the alleviation of suffering.  Only then will patients benefit from our research efforts.

Biografía del autor/a

David H. Walker, University of Texas Medical Branch

The Carmage and Martha Walls Distinguished University Chair in Tropical Diseases

Professor, Department of Pathology

Executive Director, Center for Biodefense and Emerging Infectious Diseases

Lucas Scott Blanton, University of Texas Medical Branch

Assistant Professor, Internal Medicine - Infectious Diseases


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