C. Sunny Jiang

Research in Dr. Jiang's lab focuses on the following three areas: 1) aquatic/marine microbial ecology, 2) water quality microbiology, 3) Epidemiology of exposure to recreational waters. The first area is represented by her recent publication in the journal Microbial Ecology entitled "The vertical distribution and diversity of marine bacteriophage at a station off southern California". This article describes the tremendous genetic diversity of marine bacteriophage and illuminates the interaction between bacteriophage and their hosts. This research is a continuation of her career-long pursuit to understand the role of viruses in the marine/aquatic environment and the interaction between viruses and their hosts. Her earlier research in the Gulf of Mexico and Florida coast has shown that marine viruses are ubiquitous and dynamic members of microbial ecosystems. However, interactions between viruses and their hosts in the natural environment often result in "coexistence" via lysogenization rather than lytic infection. Her current research project on "Ecology of Viruses in an alkaline hypersaline Lake, Mono Lake, California", funded by the National Science Foundation, is another example of this research interest. In this study, her group uses molecular method to uncover the genomes of unculturable bacteriophage. It is expected the results of this study will contribute to our understanding of phage genomes, the evolution of bacteriophage and phage-host interactions.

The second area of her research is represented by multidisciplinary projects focusing on understanding the source and transport of fecal contamination and human waste in coastal water. Over the past five years, her group has developed rapid and sensitive methods for detection and quantification of human viruses contamination in aquatic samples. Their results have suggested that current coastal water standards do not adequately reflect the viral quality of recreational waters. Working together with environmental engineers, coastal physical oceanographers and remote sensing scientists, they have recently discovered that surf zone water quality is impacted by multiple factors including coastal upwelling. The results challenge current paradigms for the offshore disposal of treated sewage, question the use of fecal indicator bacteria as an index of coastal water quality, and illuminate the complexity and non-linearity of processes that control the cross-shelf exchange of mass in the coastal ocean. Working directly with the City of Newport Beach and Regional Water Quality Control Board, they have investigated the relationship between fecal indicator bacteria and human viruses in Newport Bay. The results showed that the occurrence of these two types of organisms is uncoupled largely due to the differences in the source and survival of each type.

The third area of her research interest is represented by a publication on Environmental Health Perspective entitled "Evaluation of recreational health risk in coastal waters based on enterococcus densities and bathing patterns". In this paper, her group addressed the seasonal dynamics of human health risk from exposure to coastal waters. Her research group is currently developing web-based survey tools to understand the relationship between human health risk and coastal water quality.