Research
Active research projects in our laboratory include:
Plastic and pathogen pollution: A dangerous mixture
Collaborators: Chelsea Rochman, Minji Kim, Jim Moore, Elizabeth VanWormer
Plastic debris, in particular microplastics, is increasingly recognized as a global contaminant that is ubiquitous in the oceans. Compared with chemical contaminants, limited data exist on the presence of harmful pathogens as ‘hitchhikers’ on microplastics, and how microplastics may serve as vectors for pathogens in the marine environment. Investigating the association between pathogens and microplastics and subsequent impact on seafood safety was recently highlighted as an essential research need by the United Nations. Specifically, the potential interaction between microplastics and terrestrially derived, zoonotic pathogens, which can infect both animals and humans, is completely unknown. This project will provide critical data on the ability of microplastics to mediate the transport and distribution of zoonotic protozoan pathogens in the marine environment and will identify how the presence of microplastics may enhance the ability of these pathogens to infect marine wildlife. This project would also provide valuable information to shellfish producers and agencies charged with food safety, such as the Office of Environmental Health Hazard Assessment, particularly in respect to the length of time needed for oysters to clear the microplastics and pathogens from their tissues. MORE INFORMATION
Protozoan pathogens and seafood safety
Collaborators: Stefan Wuertz, Minji Kim, Graham McBride, Jim Moore
This project targets four protozoans identified as neglected pathogens in the context of seafood safety: Cryptosporidium, Giardia, Cyclospora, and Toxoplasma. The overall goal of this project is to develop and validate novel molecular methods for i) efficient screening of shellfish to simultaneously identify these four parasites; and ii) discrimination of viable parasites that can cause illness from dead organisms that are detectable but no longer infectious. We additionally aim to quantify the risk of contracting parasite-borne disease from consumption of oysters using a multi-step program that evaluates different production and distribution stages within the shellfish industry- from sea to table. This analysis tool will then enable the identification of key steps within the food supply chain where intervention strategies can most effectively reduce this risk. Our work will support the aquaculture industry through building capacity to detect important, yet under researched, protozoan pathogens in shellfish tissues, growing waters, and watersheds draining overland runoff into coastal habitats. Seafood consumers will also benefit from the availability of new methods that can efficiently test food commodities and ensure that shellfish do not harbor viable parasites than can cause illness. READ HERE
Epidemiology of human toxoplasmosis in Brazil: Do climate and habitat change drive parasite transmission?
Collaborators: Elizabeth VanWormer, Jeroen Saeij, Kathryn C Conlon, Lillian Bahia Oliveira, Renato Augusto
Toxoplasma is a globally ubiquitous pathogen that can cause congenital toxoplasmosis in thousands of newborns in the United States and Brazil. Our project will establish a new UC Davis (UCD) – Brazil taskforce of expertise on Toxoplasma research. A cutting-edge research program will integrate a novel parasite serotyping assay developed at UCD with ongoing surveillance for Toxoplasma exposure in pregnant women in Rio de Janeiro state, Brazil. We will evaluate i) if certain serotypes are associated with severe congenital disease; and ii) whether parasite exposure in women is associated with climate and land-use variables. To support our ‘Global Education For All’ vision, lectures on global health challenges facing low-middle income countries will be teleconferenced into an existing undergraduate course, while two binational workshops will target graduate student and postdoc participation. Our interdisciplinary partnership will generate novel data to support extramural grants while addressing critical gaps in research and global health education.
https://globalaffairs.ucdavis.edu/funding-resources/seed-grants/2019-20-grantees
Bridging International Expertise to Address Toxoplasma Transmission (Brazil)
Effect of climate and habitat change on coastal pathogen pollution
Collaborators: Sherillee Harper, Scott Weese, Jan Sargeant, Zeny Feng, J McClure, Spencer Greenwood
The goal of my research program in Canada is to apply a holistic, One Health approach that aims to evaluate the biophysical, climatic, and social processes that impact the transmission of pathogens through water and food. Within this framework, we have been investigating the ecology of terrestrial pathogens in marine ecosystems. Several individual projects are embedded in this program, including an investigation of protozoan pathogens in clams that are harvested for sustenance in Nunavut; evaluating presence of viable protozoan pathogens in oysters from Prince Edward Island; and development and validation of advanced molecular tools using next generation sequencing and bioinformatics to determine eukaryote pathogen profile in nearshore waters and oysters.
A novel 18S-targeted metabarcoding assay was recently developed in our laboratory for detection of diverse protozoan pathogens in environmental and clinical samples