[6] Upon joining the faculty, DeWitte, Kirsten Bos, and Verena Schuenemann analyzed skeletal remains from Black Death victims to draft a reconstructed genome in order to track long periods of the pathogen's evolution and virulence.

She first received the Ethel-Jane Westfeldt Bunting Summer Scholarship to fund her research project "The Dynamics of an Ancient Emerging Disease: Demographic and Health Consequences of Medieval Plague.

She used the grant to combined paleodemographic, paleopathological, and isotopic data from human skeletal remains to examine the intersectionality of diet, sex, socioeconomic status, health, and mortality in the context of the medieval crises of famine and plague.

[11] Based on this research, DeWitte concluded that linear enamel hypoplasia, a result of stress during an individual's life, could be an indicator of good health rather than poor.

In 2021, DeWitte co-authored an article published in the Annals of Human Biology which showed the results of skeletons of people who lived in the 1st - 5th century AD and were buried in Roman cemeteries in Britain.