Navigation Links
UD research study to shed light on emerging seaborne pathogen

A new research study at the University of Delaware seeks to determine why Vibrio parahaemolyticus, a microorganism that lives in seawater and is related to the bacterium that causes cholera, is expanding its range and virulence.

V. parahaemolyticus is a leading cause of seafood-borne illness worldwide, most frequently associated with the consumption of raw or undercooked seafood, particularly oysters and other mollusks, and crabs. Victims typically suffer from diarrhea, vomiting, fever and chills for a few days, although the infection can be fatal in those with weakened immune systems.

"This organism has been around for a long time," says Michelle Parent, assistant professor of medical technology at the University of Delaware and a co-investigator on the study. "However, only recently, in the past decade, has a new, more virulent isolate become more prevalent around the globe."

In North America, Vibrio parahaemolyticus is considered an "emerging pathogen." An estimated 4,500 cases of infection occur each year in the United States, according to the Centers for Disease Control. However, the agency suggests the number likely is much higher because labs rarely use the medium necessary to identify the organism, and cases go unreported.

"Vibrio parahaemolyticus usually causes a gastrointestinal infection that lasts two to three days, although individuals with compromised immune systems who work around seawater and get infected from a cut or open wound can die within a day," Parent says.

"This organism grows super-fast," Parent explains. "It has a replication time of six to nine minutes, which is very quick compared to other microbes."

The ultimate aim of the University of Delaware study, which is funded by a $400,000 food biosafety grant from the U.S. Department of Agriculture (USDA), is to home in on this emerging pathogen's virulence genes and determine how the organism overcomes its victim's immune system -- information that can then be used to combat, detect and prevent infection.

The aquaculture industry loses millions of dollars each year due to the contamination of oyster beds with V. parahaemolyticus during the summer months. Thus, providing oyster farmers with an agent to treat the oysters is an important overall goal and potential future direction of the research, Parent says.

Working with Parent on the project are E. Fidelma Boyd, assistant professor of biological sciences at the University of Delaware, and collaborator Gary Richards, a research microbiologist at the USDA's Agricultural Research Service in Dover, Del.

"Vibrio parahaemolyticus is most prevalent in the warmer summer months, especially in the U.S. Gulf Coast region where it occurs in high numbers," Boyd, a native of Ireland, says.

"In the past decade, the organism's geographic distribution has been extended into more northerly climes, in particular, the Pacific Northwest, most likely due to global warming. Thus, the occurrence and prevalence of the organism is likely to continue to expand," Boyd notes.

An oyster filters its food from the seawater in which it lives, ingesting not only tiny plankton but whatever else may be present in the water, including harmful bacteria such as V. parahaemolyticus. Thus, when a person consumes a raw oyster contaminated with the organism, they become infected. (Thoroughly cooking the seafood can prevent infection.)

The researchers want to determine what happens once V. parahaemolyticus attaches to a host's cells and begins multiplying.

Through a series of experiments using various infectious doses of the organism, the scientists will explore what happens when a cell is infected, and what immune response is required to eliminate infection.

"Something is happening to allow this organism to predominate," Parent says. "What makes it so powerful? Does it have some advantage in the environment?"

"We want to determine if the bacterium has acquired new genes to make it more virulent, allowing it to survive better in the aquatic environment and/or in the human gut," Boyd adds.

In a recent study published in BMC Microbiology, Boyd, Parent and their co-authors show using genomic analysis that this new highly virulent strain has acquired large pieces of DNA, which may give the bacterium a major advantage from an evolutionary point of view.

"Using molecular genetic approaches, we will delete some of these genes in the bacterium and determine how well the organism can survive and grow," Boyd notes.


Contact: Tracey Bryant
University of Delaware

Related biology news :

1. Research shows skeleton to be endocrine organ
2. Newly created cancer stem cells could aid breast cancer research
3. Dominant cholesterol-metabolism ideas challenged by new research
4. Researchers identify proteins involved in new neurodegenerative syndrome
5. Texas researchers and educators head for Antarctica
6. MGH researchers describe new way to identify, evolve novel enzymes
7. University of Pennsylvania researchers develop formula to gauge risk of disease clusters
8. University of Oregon researcher finds that on waters surface, nitric acid is not so tough
9. U of MN researchers discover noninvasive diagnostic tool for brain diseases
10. U of Minnesota researchers discover noninvasive diagnostic tool for brain diseases
11. Story ideas from the Journal of Lipid Research
Post Your Comments:
Related Image:
UD research study to shed light on emerging seaborne pathogen
(Date:4/5/2017)...  The Allen Institute for Cell Science today announces ... portal and dynamic digital window into the human cell. ... application of deep learning to create predictive models of ... a growing suite of powerful tools. The Allen Cell ... publicly available resources created and shared by the Allen ...
(Date:4/3/2017)... 2017  Data captured by IsoCode, IsoPlexis ... a statistically significant association between the potency ... and objective response of cancer patients post-treatment. ... whether cancer patients will respond to CAR-T ... as to improve both pre-infusion potency testing and ...
(Date:3/29/2017)... , March 29, 2017  higi, the health IT ... North America , today announced a ... the acquisition of EveryMove. The new investment and acquisition ... of tools to transform population health activities through the ... data. higi collects and secures data today ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... 2017 , ... Disappearing forests and increased emissions are the main causes of ... year. Especially those living in larger cities are affected by air pollution related diseases. ... most pollution-affected countries globally - decided to take action. , “I knew I had ...
(Date:10/10/2017)... ... 2017 , ... San Diego-based team building and cooking events company, Lajollacooks4u, has ... The bold new look is part of a transformation to increase awareness, appeal to ... period. , It will also expand its service offering from its signature gourmet cooking ...
(Date:10/10/2017)... ... 10, 2017 , ... Dr. Bob Harman, founder and CEO of VetStem ... The event entitled “Stem Cells and Their Regenerative Powers,” was held ... Harman, DVM, MPVM was joined by two human doctors: Peter B. Hanson, M.D., Chief ...
(Date:10/10/2017)... ... October 10, 2017 , ... USDM Life Sciences ... the life sciences and healthcare industries, announces a presentation by Subbu Viswanathan and ... presentation, “Automating GxP Validation for Agile Cloud Platforms,” will present a revolutionary approach ...
Breaking Biology Technology: