Vineyard oyster growers are expected to gather this morning to hear the details of a new state plan to control the bacteria Vp which plagued growers in the region last year, including on the Island.

In September oyster farms in Katama Bay were closed suddenly after Vibrio parahaemolyticus was found in oysters that had come from the bay. The bay was reopened three and a half weeks later.

A series of meetings followed, and Vineyard oyster farmers participated actively in discussions with state officials about the problem and the impending new control measures.

Vibrio is a naturally occurring bacterial pathogen that is more prevalent in oysters in warmer water. People can become ill after eating raw oysters with high levels of Vibrio; cooking the oysters kills the bacteria.

A Vp control plan takes effect next month that will require faster cooling and delivery of oysters, changes in handling methods for harvesters, specific requirements for icing and new rules for record keeping among commercial oyster growers.

Backed by the state Division of Marine Fisheries, the rules will be in effect from May 19 through Oct. 19. The U.S. Food and Drug Administration recommended last year that Massachusetts develop a plan to control Vp during the warm weather months to prevent illness. The result is the plan developed by the Massachusetts Department of Fish and Game, Division of Marine Fisheries and the Department of Public Health, Bureau of Environmental Health, Food Protection Program that will be discussed this morning. The plan complies with the requirements of the National Shellfish Sanitation Program.

The meeting will be held from 11 a.m. to 12:30 p.m. at the Katharine Cornell Theatre in Vineyard Haven. Meetings were held in Duxbury and Eastham on April 4.