Overview
My research at Duke has focused on understanding the dynamic between host and pathogen so as to discover and develop host-response markers that can diagnose and predict health and disease. This new and evolving approach to diagnosing illness has the potential to significantly impact individual as well as public health considering the rise of antibiotic resistance.
With any potential infectious disease diagnosis, it is difficult, if not impossible, to determine at the time of presentation what the underlying cause of illness is. For example, acute respiratory illness is among the most frequent reasons for patients to seek care. These symptoms, such as cough, sore throat, and fever may be due to a bacterial infection, viral infection, both, or a non-infectious condition such as asthma or allergies. Given the difficulties in making the diagnosis, most patients are inappropriately given antibacterials. However, each of these etiologies (bacteria, virus, or something else entirely) leaves a fingerprint embedded in the host’s response. We are very interested in finding those fingerprints and exploiting them to generate new approaches to understand, diagnose, and manage disease.
These principles also apply to sepsis, defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Just as with acute respiratory illness, it is often difficult to identify whether infection is responsible for a patient’s critical illness. We have embarked on a number of research programs that aim to better identify sepsis; define sepsis subtypes that can be used to guide future clinical research; and to better predict sepsis outcomes. These efforts have focused on many systems biology modalities including transcriptomics, miRNA, metabolomics, and proteomics. Consequently, our Data Science team has utilized these highly complex data to develop new statistical methods, furthering both the clinical and statistical research communities.
These examples are just a small sampling of the breadth of research Dr. Tsalik and his colleagues have conducted.
In April 2022, Dr. Tsalik has joined Danaher Diagnostics as the VP and Chief Scientific Officer for Infectious Disease, where he is applying this experience in biomarkers and diagnostics to shape the future of diagnostics in ID.
Current Appointments & Affiliations
Recent Publications
Adapting a commercial sample extraction protocol for biosafety level 3/4 compatible plasma metabolomics analysis.
Journal Article J Mass Spectrom Adv Clin Lab · December 2025 INTRODUCTION: Severe infections and sepsis significantly impact military operational readiness and costs through loss of duty days, high treatment rates, and medical evacuations. Early diagnosis is critical for preventing sepsis progression and mortality, ... Full text Link to item CiteHost Immune Response Profiling for the Diagnosis of Infectious Diseases.
Journal Article J Infect Dis · November 14, 2025 Recent advances in infectious disease diagnostics include the development, validation, and commercialization of new tests that measure host gene expression profiles or inflammatory protein concentrations. Interrogating host immune responses may help separa ... Full text Link to item CiteMolecular dynamics of the host response to Streptococcus pneumoniae pneumonia in baboons.
Journal Article Animal Model Exp Med · October 2025 BACKGROUND: Bacterial pneumonia remains a leading cause of morbidity and mortality worldwide despite the widespread availability of antibiotics. Novel pneumonia therapies and biomarkers are urgently needed to improve outcomes and advance personalized thera ... Full text Link to item CiteRecent Grants
Novel Host-Response Biomarker Diagnostics for Invasive Aspergillosis
ResearchAdvisor · Awarded by National Institute of Allergy and Infectious Diseases · 2024 - 2029AMR Challenge Award 2
ResearchPrincipal Investigator · Awarded by National Institutes of Health · 2019 - 2025Rapid, point-of-care, host gene expression test for presymptomatic viral infection and to distinguish bacterial from viral illness
ResearchPrincipal Investigator · Awarded by Department of Defense · 2021 - 2024View All Grants