In recent years, there has been increased attention paid to the human health risk associated with consumption of raw oysters, due to the presence of the Vp. bacteria. Vp. thrive in warmer temperatures with the bacteria multiplying as water temperatures increase. Post harvest handling of oysters during warm summer months can significantly increase Vp. loading in oysters. The more Vp. present in oysters the greater the risk of infection; the consumption of raw oysters with high counts of Vp. can cause gastrointestinal illness and in severe cases it can be lethal.

Many states south of Massachusetts have historically been required and continue to aggressively manage this risk through detailed and restrictive management plans and seasonal harvest area closures. Until 2012, Massachusetts was not required to have Vp. control measures in place because NSSP water temperature and illness thresholds had not been met or exceeded in oyster harvest areas. However, due to warming air and water temperatures, this is no longer true. In 2011, Massachusetts had two illnesses attributed to Eastern Cape Cod Bay. This occurrence met the illness threshold. In 2012 and 2013 there were significant increases in the number of illnesses attributed to Massachusetts oyster areas with a drop in the number of illnesses in 2014. As a result, Massachusetts is required by the US Food and Drug Administration (USFDA) to have A Vp. Control Plan for Oysters during the warm weather high Vp. risk months (mid-May through mid-October).

To meet these federal USFDA mandates pertaining to the consumption of raw oysters and Vibrio parahaemolyticus (“Vp.”) health related risks; the Commonwealth of Massachusetts annually develops and submits a Vp. Control Plan for their review. This is accomplished through a joint effort between the Division of Marine Fisheries (MarineFisheries), who regulate shellfish growers and wild shellfish harvesters, and the Department of Public Health (Public Health), who regulate the seafood dealers that purchase product from these growers and harvesters. The Vp. Control Plan is designed to better manage the time-to-temperature related conditions relative to oyster harvest and handling in Massachusetts and prevent or limit the post-harvest growth of Vp. bacteria in oysters. To ensure that the measures set forth in the Vp. Control Plan, pertaining to oyster growers and wild oyster harvesters, are enforceable, MarineFisheries has established implementing regulations at 322 CMR 16.05.

2017 Vibrio Control Plan

2016 Vibrio Control Plan

2015 Vibrio Control Plan

Other 2015 Documents

2014 Vibrio Control Plan

Other 2014 Documents

2013 Vibrio Control Plan

For more information, you may contact Marinefisheries at 617-626-1520 or the Department of Public Health at 617-983-6700.