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Vice Chair for Faculty, Department of Epidemiology

Contact Info

615 N. Wolfe Street, Room W6511

Research Interests

epidemiology; genetics; infectious disease; diarrhea; malnutrition; HIV; snp; amebiasis; leishmaniasis; cholera; acute flaccid myelitis; COVID-19;long COVID
Experiences & Accomplishments
Johns Hopkins Bloomberg School of Public Health
Johns Hopkins Bloomberg School of Public Health
Wesleyan University
My primary research interest is on understanding the relationship between host, infection and immunity. Specifically, I am interested in human genetics and the intersection with pathogen genetics, inflammation and the immune system. The exposure to an environmental pathogen is critical to risk, but genes in the host can influence innate and adaptive immunity and thus the risk of disease and its severity. My goal is to identify the underlying mechanisms of infectious disease by identifying host genetic variants that alter or influence our immune response.
I work with adult and pediatric populations within the United States and Internationally. My research encompasses viruses like hepatitis B and C and HIV, enterovirus and SARS-CoV-2 as well as a strong focus on enteric infections that affect young children in poor sanitary conditions.
For a more general genetics focus, I am leading the genetics arm of the Environmental Influences on Child Health Outcomes (ECHO) study that includes 40,000 children and mothers. This study provides us the opportunity to examine the interactions of environment and genetics and its impact on child health and disease.

And with the COVID-19 pandemic we have played a role in examining the host genetics of COVID-19 severity in our study COVIDgene as well as understanding long COVID in an International study of post acute symptoms following COVID-19 infection. For more information please link to
Honors & Awards
2002  NHGRI Directors Distinguished Service Award, NIH
2004  Fellows Award for Research Excellence, NIH
2005  NHGRI Intramural Research Award, NIH (1 of 3 awarded to an outstanding research fellow)
2012  Teaching Excellence, Johns Hopkins Bloomberg School of Public Health
2013 Sherrilyn and Ken Fisher Center Award, Johns Hopkins Medical Insitutions
2016 Catalyst Award, Office of the Provost, Johns Hopkins University
2022  Teaching Excellence, Johns Hopkins Bloomberg School of Public Health
Select Publications
Click here for a full list of my PubMed citations
Genetics of Malnutrition and Enteric Disease
Genetics of glaucoma related traits
Genetic susceptibility to leishmaniasis
Hepatitis C
Genetics of Acute Flaccid Myelitis
COVIDgene: Host Genetics of COVID-19