Changes in the frequency, intensity, and duration of extreme weather events is likely to affect the ecology of pathogenic Vibrio bacteria in the Chesapeake Bay, the largest estuary in the U.S., which is already experiencing twice the global average rate of sea-level rise. Human health risks associated with vibrios are primarily related to the consumption of contaminated seafood or exposure to pathogens during water-based recreational activities. Since vibrios cannot be eradicated from the Chesapeake Bay, the development of predictive models based on conditions favoring their survival in the marine environment will inform decision makers to devise policies to protect public health. Through the completion of this project the research team will produce a comprehensive assessment of the impact of extreme events on the prevalence of pathogens in the Chesapeake Bay associated water, plankton, and oysters, considering the environmental and geophysical processes that modulate these relations. The outcomes of this research, disseminated through various channels (websites, news media and healthcare agencies), will assist in critical decision making to minimize public health risk of interaction with vibrios in the Chesapeake Bay area. The results may be useful to other locations in the United States and other countries to help prevent an outbreak of disease as the vibrios are known to occur naturally in the aquatic environment. The project is jointly supported by NSF and by the National Institute for Environmental Health Sciences (NIEHS).
Prior studies clearly indicate that the frequency of Vibrio spp. occurrences are influenced by environmental factors, and under certain conditions, these bacteria enter into a viable but nonculturable (VBNC) state. Detecting the presence of pathogenic vibrios, including VBNC cells, is critical because loss of culturability does not guarantee loss of virulence. This research will enhance knowledge on understanding of occurrence and abundance of clinically important vibrios in the Bay using a fundamentally transformational approach - a satellite remote sensing inspired simulation and prediction risk model integrating ecological theory (culturable and VBNC) of pathogens (V. cholerae, V. vulnificus and V. parahaemolyticus) through exhaustive sampling (in water, plankton and oysters) in the region. Three objectives of the study are to (i) characterize the prevalence of these culturable and VBNC vibrios using recently developed detection method in the Chesapeake Bay water, plankton and oysters; (ii) Investigate the impact of extreme heat events, extreme precipitation events and other key environmental and geophysical factors (e.g. plankton blooms, sea surface height, salinity) on the prevalence of pathogenic Vibrio spp.in Chesapeake Bay and further investigate how this association differs between culturable versus VBNC states and (iii) develop satellite- based predictive risk models for vibriosis outbreaks in the Chesapeake Bay area to inform public health preparedness. A combination of observational data analysis and modeling will be used to accomplish the goals, test hypotheses, and explore alternate mechanisms.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
