Title: Interactions between climate, host life history and viral diversity across a transhemispheric range of marine ecosystems

Speaker: Mingli Zhao (PhD Candidate, UMBC-IMET)

Host: Dr. Eric Schott

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https://umces-edu.zoom.us/rec/share/s7yD1dZZtZ8EGFcHef1kdqOyeo-Bg4e7YBPgQS_tl99p0nbOjhr4fuIdAdQQTtBv.mc6DnoxUAE1E4eGS

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Abstract: Marine infectious diseases and pathogens substantially impact the structure and function of marine communities by causing mortalities and altering host behaviors. The interactions between host and pathogen, determining the epidemiological outcomes, are affected by many factors including climate, host life history, and human activities. Studies on marine disease epidemiology and ecology, including both natural and anthropogenic transmission pathways, are necessary for better understanding how these factors potentially influence the host-pathogen interactions. Viruses constitute a significant part of marine pathogens, causing severe infectious diseases and mortalities in many marine organisms, including crustaceans. Virus-related diseases and mortalities have been identified and reported in the Atlantic blue crab, Callinectes sapidus, for more than half a century. With a wide geographic distribution across both hemispheres and the temperature-dependent variable life histories, blue crab and its pathogenic viruses constitute a well-suited pathosystem for investigating the potential influences of climate, seasonality, and host life history on viral disease emergence and spread in marine ecosystems. This dissertation applied the “blue crab-virus” pathosystem, to investigate factors that potentially influence the interactions between blue crab and its viral symbionts. The studies mainly focused on three objectives: 1) Investigate the influences of climate, seasonality, and host life history on the prevalence and disease ecology of a virus that is pathogenic to blue crab. 2) Assess the influences of climate, seasonality, and host life history on viral genetic diversity and genetic structures across a wide spatial and temporal ranges. 3) Characterize genome sequences and biological characteristics of newly identified viruses in blue crabs. The studies encompassed in this dissertation demonstrate, in a single host species, that climate, temperature, and host life history traits drive patterns of virus species diversity and genetic variation across the entire range of the host. One significant revelation was the evidence of long-distance movement of virus pathogen genotypes by human transport of infected blue crabs among states in the United States. The dissertation concludes with a discussion of the potential for next generation sequencing to discover and study the movement of known and newly discovered viruses in marine hosts.

For meeting information please contact imetdirectorsoffice@umces.edu.