Valerie Harwood

Professor and Chair, Department of Integrative Biology, College of Arts & Sciences

Organization: University of South Florida

Education: Ph.D. in Biomedical Sciences, Old Dominion University & Eastern Virginia Med School

The Harwood Environmental Microbiology Laboratory at USF focuses on microbial water quality. We are interested in the survival of sewage microorganisms in "secondary" habitats such as water, sediment, sand, and vegetation. Another focus of the lab is the ecology and virulence of pathogens that are native to aquatic habitats, such as Vibrio vulnificus.

A major focus of the lab over the past two decades has been microbial source tracking (MST), which endeavors to determine the sources of fecal pollution in water bodies. Because the fecal indicator bacteria (fecal coliforms, E. coli, Enterococcus species) used to assess water quality are shed in the feces of almost all animals, they provide limited information on human health risk, and almost no guidance on how to remediate a polluted water body. The MST methodologies we use and develop are based on nucleic acid sequences of viruses or bacteria that are strongly associated with the feces of a particular host species, or group of host species, e.g. human-associated, cattle-associated, ruminant-associated.

MST findings have implications for how stormwater is managed, how beach water quality is monitored, and how water quality is maintained or improved throughout the U.S. and in other countries. We employ molecular biology methods such as quantitative PCR (qPCR) and microarray to detect and quantify genes of bacteria and viruses that indicate contamination from specific sources. Our studies sites range from Florida to New Zealand and Australia.

Other research interests also include qPCR quantification and population biology of the marine bacterium Vibrio vulnificus, an opportunistic pathogen that can cause septicemia and rapid death. V. vulnificus is a significant cause of illness and death in Florida and other Gulf Coast states, generally due to consumption of raw shellfish but also from wound infections. 

Subject Areas:
Ecology, Water Quality

Title Sponsor(s) Dates
Coastal SEES Collaborative Research: Integration of human behavior and perception into a risk-based microbial water quality management approach National Science Foundation 2015 - 2018 2018
Determining Sources and Risk of Fecal Pollution in Tampa Bay Tributaries Environmental Protection Commission of Hillsborough County 2015 - 2017 2017

Affiliated Faculty