Increase in Vibrio parahaemolyticus illnesses associated with consumption of shellfish from several Atlantic coast harvest areas, United States, 2013
Posted October 21, 2013 11:45 AM ET
At a Glance:
See Interstate Shellfish Sanitation Conference for a list of Shellfish Closures, Reopenings, and Recalls.
Latest Case Count Map
Latest Epi Curve
Investigation as of September 30
Public health investigators are using the national Cholera and other Vibrio Infections Surveillance (COVIS) system [PDF - 4 pages] to collect food histories. Food histories have been reported for 82 ill persons. Of these, 75 (91%) reported eating raw oysters or raw clams during the 7 days before their illness began.
State health departments work with regulatory partners to trace the source of the shellfish. These efforts have determined that raw oysters and clams consumed by Ill persons originated from shellfish harvest areas in Connecticut, Massachusetts, New York, and Virginia.
The Interstate Shellfish Sanitation Conference maintains a list of shellfish harvest area closures and recalls. Harvest areas to which illnesses were traced remain closed in Virginia (closed July 12) and Massachusetts (closed August 30). New York closed harvest areas which were associated with illnesses from June 29 to September 14and Connecticut closed illness associated harvest areas from August 2 to September 17. Massachusetts issued a recall of oysters originating from harvest areas associated with illness and Connecticut issued a recall of oysters and clams originating from illness associated harvest areas.
Illnesses are still being reported, but have decreased since the warmest months. It is unlikely that all harvest areas associated with illnesses have been identified. It is likely that many illnesses have occurred that were not detected through surveillance because some people do not seek medical care, diagnostic testing is not always performed, and some laboratories do not routinely use the specific culture plate necessary to test for Vibrio bacteria. The investigation is ongoing.