By: James Peacock

The health officials of the Seattle & King County Health Department have announced that they are looking into two separate outbreaks of foodborne illness. Foodborne illness outbreaks have been linked to the Salted Sea and The White Swan, both located in Seattle. In both cases, the outbreaks were linked to oysters served at the establishments. For one restaurant, Vibrio bacteria are confirmed to have caused the illnesses. For the other outbreak, Vibrio is highly suspected, but further testing is required to confirm this. The two outbreaks were announced to the public this week, with the first announcement coming on July 12.

Salted Sea

On July 12, the Public Health Department reported that they are investigating an outbreak of Vibrio poisoning linked to the Salted Sea. The Salted Sea, which is located on Rainier Ave in Seattle, Washington, serves raw oysters as a menu item. This outbreak has sickened three people. Only one person has a laboratory-confirmed case of Vibrio poisoning, while the other two cases have symptoms that suggest vibrio poisoning. Two of those sickened in the outbreak were part of a dinner party held at the restaurant on June 9, 2017. The third person was sickened in a separate dinner party that took place on June 17, 2017. The outbreak was first brought to the attention of the Public Health Department on June 22. Health investigators visited the restaurant after the outbreak was reported. They found, over the course of an inspection, that there were no glaring infractions that would promote the spread and contamination of Vibrio in the restaurant. Since the oysters sold at the restaurant were harvested from several different growing areas in Washington State, health officials have been unable to pinpoint a specific source of the contamination. Investigators also reported the illnesses to the Washington State Department of Health Shellfish Program.

The White Swan

The next day, on July 13, the Public Health Department reported on another foodborne illness outbreak linked to a Seattle restaurant. Illnesses were linked to the White Swan Public House on Fairview Ave. There are a total of six people sickened in the outbreak, from two separate dinner parties. The parties took place on different days, June 30 and July 3. The symptoms presented by those sickened in the outbreak suggest that they have Vibriosis, but because no laboratory testing was done in this instance, norovirus poisoning cannot be ruled out. The outbreak was brought to the attention of the health department on July 6. Investigators visited the White Swan on that same day to inspect the establishment. There were no factors found in the restaurant that would promote the growth of Vibrio bacteria. Because of the lack of evidence implicating White Swan in the outbreak, health officials attempted to track down the oyster supplier in an effort to pinpoint a source. However, as was the case, the restaurant received oysters from several different suppliers. With growing areas in both Washington State and New Zealand, investigators were unable to name a source of the contaminated oysters. As was the case with the other outbreak, health officials reported the illnesses to the Washington State Department of Health Shellfish program.

Recent Washington Oyster Outbreak

Oysters are a very common source of foodborne illness outbreaks, as they are often served raw. Washington State is also not unfamiliar with oyster-related outbreaks. Earlier this year, there was an outbreak of norovirus linked to raw oysters sold across the state. As many as 55 people may have been sickened in this outbreak across the state. People sickened in that outbreak ate at various restaurants, all of which had common suppliers. Twenty-two different restaurants were tied to the outbreak. Interestingly, both The White Swan Public House and the Salted Sea each had one person report a case of norovirus poisoning after eating at the restaurants. The investigation traced the oysters back all the way to the growing areas from which they were harvested from. They then closed these growing areas, which supplied oysters to more than 30 different companies.

Vibrio

Vibriosis, the illness caused by the dozen or so species of Vibrio, affects about 80,000 people per year. These infections cause about 500 instances of hospitalization and 100 deaths per year. These bacteria can cause illness anywhere between 4 and 96 hours after exposure. Symptoms of a Vibrio infection include diarrhea, vomiting, abdominal cramps, nausea, vomiting, and fever. These illnesses will usually stop between 2 to 5 days after symptoms appear, and will rarely cause hospitalization or a need for antibiotics. Vibrio poisoning is connected to raw shellfish and other raw fish products. In many cases, oysters are the reason for Vibrio outbreaks taking place.

Norovirus

Norovirus infections represent the most common source of foodborne illnesses in the United States. The Center for Disease Control estimates that there are between 19 and 21 million cases every year. Almost 2 million people are forced to contact a medical professional because of their Norovirus infection. Between 56,000 and 71,000 people are hospitalized every year because of Norovirus, and there are around 1,000 deaths annually. The vast majority of Norovirus cases are spread from person to person, because the virus is among the most contagious of the foodborne pathogens. Outbreaks of Norovirus are commonly associated with leafy greens, fresh fruits, and shellfish. Norovirus outbreaks are especially dangerous in areas where contact with other people is common. Healthcare facilities, schools, and daycares, cruise ships, and catered events are some of the most common places that a Norovirus outbreak may take place. Symptoms of Norovirus poisoning will begin to rise between 12 and 48 hours after the first exposure to the pathogen. Commonly, a Norovirus infection will produce symptoms including diarrhea, nausea, vomiting, and abdominal cramping. Fever, headaches, and body aches are less common symptoms but still possible. Most cases of Norovirus poisoning will clear up on its own within 3 days, but in some cases, the illness may worsen. Norovirus can also cause dehydration, which will present with symptoms including a decrease in urination, dry mouth, dizziness upon standing, and dry throat. Young children, the elderly, and those with suppressed immune systems are at an increased risk of contracting a serious case of Norovirus poisoning and becoming dehydrated. If you or a loved one begins to show the symptoms of Norovirus poisoning, it is a good idea to contact a medical professional.

 

Sources:

http://www.kingcounty.gov/depts/health/communicable-diseases/disease-control/outbreak/salted-sea.aspx

http://www.kingcounty.gov/depts/health/communicable-diseases/disease-control/outbreak/white-swan-public-house.aspx