How four 91制片厂 researchers are working to keep illness off the raw bar

Wednesday, August 27, 2014
steve jones in boat with student

Steve Jones, research associate professor of natural resources and the environment and a water quality specialist, samples Great Bay with Ph.D. student Meg Hartwick.

Consider the gifts of the oyster. The humble mollusk gives us slurpworthy dining pleasure and cleaner water, thanks to each oyster鈥檚 filtering of up to 40 gallons of water daily. Locally, it鈥檚 launched a growing aquaculture industry in Great Bay.

But the oyster can also give a gift that makes us wish we鈥檇 never considered the mollusk: Vibriosis, an illness that causes both gastrointestinal distress and, most likely, a lifelong aversion to the briny bivalve. Now, as incidences of Vibriosis rise sharply in the Northeast, an interdisciplinary team of researchers at 91制片厂 are bringing science to the shellfish industry to stop the food-borne illness before it makes it to the halfshell.

We get sick when oysters 鈥 commonly eaten raw -- are contaminated with a pathogenic strain of a ubiquitous, fast-growing group of bacteria called Vibrio, in particular, the species of Vibrio called parahaemolyticus. As our appetite for oysters 鈥 particularly in the warm summer months 鈥 has increased and water temperatures have risen due to climate change, incidences of Vibriosis have also gone up. So have closures of shellfish beds: 2013 saw a jump in both Vibriosis and an unprecedented level of shellfish bed closures in Massachusetts and Connecticut.

鈥淭his whole procedure of closing is very troublesome to the industry,鈥 says Steve Jones, research associate professor of natural resources and the environment. Particularly problematic, Jones says, is the imprecise, often weeks-long lag between an outbreak of human illness and the closure of the bed from which the guilty oyster came. 鈥淭he more accurately we can predict conditions the more we can narrow the time frame for closures.鈥

For the three-year study, funded by the National Science Foundation through NH EPSCoR, Jones is working with Vaughn Cooper and Cheryl Whistler, both associate professors of microbiology, and Tom Safford, associate professor of sociology. With Great Bay and its 10 commercial oyster farms as their laboratory, they鈥檙e attacking illness-producing Vibrios on many fronts.

91制片厂 graduate students tong for oysters in Great BayIn Great Bay, a team of undergraduate and graduate students collect oysters to look at environmental conditions that might favor Vibrio parahaemolyticus.

Jones, a water quality specialist, and a team of undergraduate and graduate students are looking at environmental conditions that favor Vibrio parahaemolyticus, warmer water due to climate change chief among them. Salinity 鈥 which decreases during unusually heavy rainstorms 鈥 pH levels, dissolved oxygen, and turbidity are also on the researchers鈥 radar. Working out of 91制片厂鈥檚 Jackson Estuarine Laboratory at Adams Point in Durham, Jones is drawing on a deep dataset of Great Bay and Oyster River conditions, which 91制片厂 scientists have been monitoring for nearly a decade.

鈥淲hat we鈥檙e really interested in is being able to tell shellfishermen 鈥榙on鈥檛 harvest now,鈥欌 says Jones, who is also associate director of the NH Sea Grant Program. 鈥淲e want to look at conditions and be able to predict when pathogenic strains of Vibrio parahaemolyticus are present.鈥

Back in the lab, microbiologists Cooper and Whistler use population genetics and latest genomic techniques to determine which strains of Vibrio parahaemolyticus are making people sick and whether they鈥檙e coming from somewhere else or evolving here in Great Bay to become pathogenic. They鈥檙e also probing the dynamics of environmental factors as they interact with other microbes within the oyster on pathogenic Vibrios.

鈥淚t鈥檚 literally genetic forensic epidemiology to understand what strains are being associated with diseases during a given season,鈥 says Cooper. 鈥淲e really don鈥檛 know what makes a Vibrio parahaemolyticus pathogenic. There are lots of strains out there, and only some of them will make you sick.鈥

And how to convey this cutting-edge scientists to shellfish growers and eaters? That's where Safford comes in. Looking at survey data, he鈥檚 interested teasing out how the general public trusts and believes scientists, information the researchers hope will ensure better reception of cautionary information about outbreaks of Vibriosis.

鈥淯ltimately, if you want people to be safe, it鈥檚 not just about saying 鈥榟ey, the science said it鈥檚 not safe,鈥欌 Safford says. 鈥淚f you鈥檙e going to use information that came from Vaughn and Steve and Cheryl about the level of risk of eating or harvesting shellfish, you need to understand that maybe just talking about scientific information may not resonate with many people.鈥

These four 91制片厂 researchers are part of a larger team that includes oyster farmers and university scientists from New Hampshire and Maine. Under the umbrella of the , a project of Maine and New Hampshire EPSCoR, the collaboration aims to bring an interdisciplinary approach to coastal sustainability.

And while each partner brings a unique skill to the raw bar, they鈥檙e aligned in the ultimate goal: To keep oyster lovers healthy by keeping Vibrios off the menu.

In addition to NH EPSCoR funding through the National Science Foundation, this work has received funding from NH Sea Grant and the NH Agricultural Experiment Station. Read this work.