Prevots Research Group

Epidemiology and Population Studies Unit

The current primary research focus of the Epidemiology and Population Studies Unit is to understand environmental risk factors for nontuberculous mycobacterial (NTM) disease by associating population data with environmental data and applying geospatial techniques. Our research group focuses on the epidemiology of NTM disease, including estimating the burden and trends of NTM in the United States, as well as risk factors for disease susceptibility and progression.

NTM are environmental mycobacteria typically acquired from soil and water. Thus, our research is interdisciplinary because we draw on expertise from other fields, including microbiology, geology, and climate science. Because NTM is not a reportable condition, we have identified other large, population-based datasets for estimating burden and trends. To identify risk factors for infection and disease, we identify large national and subnational human population datasets and link them to environmental and climate data. We are also involved in NTM clinical research related to identifying determinants of disease susceptibility and progression.

We are a dynamic and friendly group of Ph.D. epidemiologists and trainees with advanced training in epidemiologic study design and analysis and experience in public health settings, as well as clinical and laboratory research. Our group conducts research and mentoring in a collaborative environment and values a team approach.

D. Rebecca Prevots, Ph.D., M.P.H. (She/Her/Hers)

Chief, Epidemiology and Population Studies Unit

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Education:

Ph.D., M.P.H., University of Michigan

Languages Spoken: French, Spanish, Portuguese

Dr. Prevots began her public health research career in 1985 as a public health advisor for the New York City Department of Health. In 1988 she earned her M.P.H. from the University of Michigan, and then in 1991 her Ph.D. in epidemiology. Upon completing her Ph.D., she joined the Epidemic Intelligence Service at the CDC. She joined NIAID in 2003, and in 2007 she became head of the newly created Epidemiology and Population Studies Unit.

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Samantha Bents, B.A. (She/Her/Hers)

Postbaccalaureate IRTA Fellow

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Education:

B.A.,2022, Princeton University, Princeton, NJ

Samantha Bents is a Postbaccalaureate IRTA Fellow with NIAID and the NIH Fogarty International Center. She earned her B.A. in ecology and evolutionary biology from Princeton University with a concentration in global health and health policy. Her recent work has focused on employing mechanistic and statistical analyses to study respiratory syncytial virus (RSV), nontuberculous mycobacteria (NTM)...

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Kam S. Ho, M.D. (He/Him/His)

Pulmonary Fellow

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Education:

M.D., 2018, Royal College of Surgeons in Ireland, Dublin, Ireland

Languages Spoken: Cantonese

Kam is a pulmonary research fellow in the Epidemiology and Population Studies Unit. His research focuses on the clinical significance of the first positive nontuberculous mycobacteria culture among patients with cystic fibrosis. His goals are to better inform physicians and guide clinical decisions in the initiation of long-term antimicrobial therapy. He will complete his pulmonary and critical...

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Jennifer Laurel Kwan, Ph.D. (She/Her/Hers)

Mathematical Statistician

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Education:

Ph.D., Epidemiology, 2010, University of California Davis, CA

B.A., Biological Sciences, 2005, Whittier College, CA

Dr. Kwan received her Ph.D. in epidemiology from the University of California, Davis, with designated emphasis in vector-borne disease. As a student nestled between the medical and veterinary schools, she was well trained in zoonoses and the complex interfaces between people, animals, and their environment. She specializes in study designs for both complex clinical trials and observational studies...

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Ettie M. Lipner, Ph.D., M.P.H. (She/Her/Hers)

Staff Scientist I

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Education:

Ph.D., Columbia University Mailman School of Public Health, New York, NY

M.P.H., University of California Berkeley School of Public Health, Berkeley, CA

B.A., William Smith College, Geneva, NY

Ettie is a staff scientist in the Epidemiology and Population Studies Unit in the Laboratory of Clinical Immunology and Microbiology. Her work focuses on understanding the environmental determinants and geographical variation of nontuberculous mycobacterial (NTM) pulmonary infection and disease in both the general and cystic fibrosis populations. Most recently, she focused on how trace metals in...

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Julia E. Marshall, B.S. (She/Her/Hers)

Postbaccalaureate Fellow

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Education:

B.S., 2021, Duke University, Durham, NC

Julia Marshall is a postbaccalaureate research fellow in the Epidemiology and Population Studies Unit. Her research focuses on spatiotemporal patterns of nontuberculous mycobacteria disease in the United States. Her general research interests include environmental transmission of infectious microbes and the use of geospatial methods. She will complete her Master of Philosophy in population health...

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Rachel A. Mercaldo, Ph.D. (She/Her/Hers)

Research Fellow

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Education:

Ph.D., 2021, University of Georgia, Athens, GA, USA

Dr. Rachel Mercaldo is a research fellow in the Epidemiology and Population Studies Unit, NIAID. She earned her Ph.D. at the University of Georgia, studying tuberculosis, Zika virus, and COVID-19 infection and disease dynamics through a mixture of spatial epidemiology, simulation, and machine learning methods. Her current research focuses on determinants of exposure and infection in the...

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Collin E. Powell, M.S. (He/Him/His)

Research Analyst

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Education:

M.S., University of Colorado at Denver, Denver, CO

M.S., University of Colorado Boulder, Boulder, CO

B.A., Oberlin College, Oberlin, OH

Collin is a research analyst in the Epidemiology and Population Studies unit. He is a statistician and applied mathematician in generalized research areas which include geospatial statistics, machine learning, functional interpolation, and radial basis functions. In 2022, he received his master’s degree in statistics from the University of Colorado Denver. In 2011, he received his master’s in...

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