Vibrio is a naturally occurring bacteria common in shellfish, clams, oysters, lobsters and shrimp. It's not visible, but it can become a problem in uncooked or raw shellfish. Last year, there was a more than 40 percent spike in vibrio-related food-born diseases, compared to four and six years prior. Kristin DeRosia-Banick is an analyst with the state Department of Agriculture. The department met with shellfish harvesters Tuesday in Bridgeport to discuss regulator issues surrounding Vibrio, which may be harmful to humans. "The Vibrio that we're concerned about is called vibrio parahaemolyticus. There's a number of species. This one can cause gastrointestinal upset, so nausea, vomiting, diarrhea. In most cases, someone will recover. If someone has any underlying health conditions -- liver disease, any immune system issues, then they might become more ill and require hospitalization," she said. In an effort to keep the problem at bay, commercial harvesters are required -- during these warmer months -- to refrigerate shellfish in a shorter amount of time. "So, while it's onboard the boat. If it's at 70 degrees say, the bacteria might be doubling every two hours or three hours. Once it's under refrigeration, that process slows dramatically. So, we ask them to get it to 50 degrees as quickly as possible," said DeRosia-Banic. It can be difficult for some harvesters who have to rush back to land for refrigeration. But the agriculture department says the local industry is doing a good job complying to the rules. Whereas surrounding states such as New York, Massachusetts, and New Jersey each had outbreaks last year. Connecticut did not. DeRosia-Banic attributes to the state's control plans.