Karena Nguyen, Ph.D.
Assistant Director of Postdoctoral Services
Office of Graduate and Postdoctoral Education | Georgia Institute of Technology
More than 2.5 billion people lack access to adequate water and sanitation, and millions of people worldwide suffer from parasite infections associated with poor water quality. To maximize human health outcomes, I approached disease surveillance and mitigation from microbiological and ecological perspectives. As an environmental microbiologist, I used molecular markers to detect sources of contamination in water bodies to inform risk assessment and remediation strategies. As a disease ecologist, I was interested in understanding ecological drivers of transmission so interventions could more effectively disrupt parasite exposure and infection. I addressed these research goals by combining observations in natural systems and experiments in the lab and field.
​
Notable research projects are included below. A full list of publications can be found on Google Scholar.
Schistosomiasis
Global climate change is impacting the emergence, re-emergence, prevalence, and incidence of infectious diseases worldwide, including diseases caused by parasites.
In one study, I found that the additive effects of high temperature and low water viscosity allow the miracidial and cercarial life stages of the parasite Schistosoma mansoni to travel farther, which increases the likelihood of miracidia and cercariae encountering snails and humans, respectively (Nguyen et al. 2020, International Journal for Parasitology).
In collaboration with quantitative ecologist Dr. Philipp Boersch-Supan, we estimated the thermal optimum of transmission for S. mansoni, and successfully showed that interventions targeting temperature-sensitive parts of the life cycle can shift the thermal optimum of transmission by overriding thermal constraints on transmission. We then used surface water temperatures from a retrospective global model to project transmission phenologies for past decades across endemic areas. Seasonal transmission risk peaks when water temperatures approach the thermal optimum for transmission! Our results suggest that fresh water warming associated with global climate change will likely decrease infection risk in areas where water temperatures currently above the thermal optimum for transmission & vv. (Nguyen and Boersch-Supan et al. 2021, PNAS).
Water Quality
Identifying major sites of pollution and the sources of pollution can help inform and direct water quality management strategies. In one study, I demonstrated that the concomitant use of fecal indicator bacteria (FIB) and microbial source tracking (MST) markers vastly improves water quality assessment and helps regulatory agencies avoid unnecessary, costly remediation strategies (Nguyen et al. 2018, Water Research).
Other Collaborations​
I have also participated in other projects, including studies that tested the effects of pesticides and resource availability on host-parasite dynamics, examined how thermal mismatches may predict infection prevalence of the chytrid fungus Batrachochytrium dendrobatidis (Bd) in amphibians, and explored links between emerging infectious diseases and global food production.
Visit my ResearchGate profile >>
