Prevalence of Vibrio vulnificus and Vibrio parahaemolyticus in the Maryland Coastal Bays

Undergraduate #38
Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology

Veronica De Pascuale - Oberlin College
Co-Author(s): Ligia Da Silva, University of Maryland Eastern Shore, Princess Anne, MD

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The bacterial family of Vibrionaceae is indigenous in the marine estuarine environments such as the Maryland Coastal Bays. Vibrio vulnificus and Vibrio parahaemolyticus are both pathogenic bacteria. Understanding the distribution of Vibrio species is crucial because of the health concerns associated with the bacteria. The aim of this study was to evaluate the overall
abundance of bacteria with a focus on Vibrio species in the Maryland Coastal Bays. Seawater samples were collected from 10 different sites that differ with regard to water quality. The total bacteria count (TBC) was determined by two methods: Total plate count and Epifluorescence microscopy. The mostprobable-number (MPN) methodology was used to estimate the population of Vibrio parahaemolyticus and Vibrio vulnificus. In addition to the bacteriological analysis, the environmental parameters of temperature and salinity were measured using YSI 6600 multiparameter meter. The average total bacteria count was 2.21 log CFU/ml. Vibrio vulnificus comprised 5% of the total bacteria count while Vibrio parahaemolyticus comprised only 2% of the total bacteria count. Vibrio vulnificus ranged from 0.30 to 2.48 log MPN/ml at the sites tested. Lower Vibrio parahaemolyticus count was observed at the sites with a range of 0.30 to 1.97 log MPN/ml. There was no significant correlation between the environmental parameters and the Vibrio spp. Since both Vibrio vulnificus and Vibrio parahaemolyticus peak in the summer, there is a potential for a risk of wound infections and gastrointestinal illness based on this data. Further research could be on determining a correlation between phytoplankton abundance and Vibrio spp. in coastal areas since there is a lack on information on this topic across scientific literature. More specially, the phytoplankton correlation would focus on the total pathogenic abundance of Vibrio parahaemolyticus and Vibrio vulnificus species containing their corresponding pathogenic genes and its preference on specific algal species.

Funder Acknowledgement(s): I would like to thank the National Science Foundation for the opportunity to conduct marine research as an undergraduate at the University of Maryland Eastern Shore. I would also like to thank the LMRCSC and NOAA Educational Partnership Program for financial support while at the University of Maryland Eastern Shore.

Faculty Advisor: Ligia Da Silva,