A Seattle restaurant is temporarily closed because of illnesses reported by customers. The Pho Aroma restaurant will not reopen until public health officials give their OK.

The local health department, Public Health Seattle & King County, reported Thursday that is is investigating at least five cases of suspected norovirus linked to the restaurant; three customers and two employees. The department first learned of the possible outbreak Tuesday.

“Environmental Health investigators visited and closed the restaurant on Jan. 17,” according to a news release issued by the health department Thursday night. “During the field inspection, investigators identified two employees who experienced similar symptoms after the ill customers’ meal date of Jan. 13.”

Health officials reported they do not yet have results of laboratory tests, but the sick people’s symptoms of nausea, vomiting and diarrhea are consistent with norovirus. The highly contagious virus, often referred to as stomach flu, can easily contaminate foods or beverages if proper handwashing and other simple food safety procedures are not followed.

The exact food or drink item that caused the illnesses has not been identified, though this is not uncommon for norovirus outbreaks where multiple food items may be contaminated, according to the Seattle health department.

Sick employees cannot return to work at the restaurant until they have been symptom free for at least 48 hours. People infected with the virus are contagious before symptoms begin and for at least two days after symptoms subside.

“The restaurant is working cooperatively with public health; they closed on Jan. 17 to allow time to complete a thorough cleaning and sanitizing of the restaurant,” according to the health department news release.

“Environmental health investigators plan to revisit the restaurant before re-opening to ensure employees are maintaining a high level of hand hygiene and that proper cleaning and sanitizing of the restaurant was completed.”

Norovirus illness often has a sudden onset of nausea and vomiting and/or watery diarrhea with cramps. A low-grade fever, chills, and body aches sometimes occur. Norovirus rarely causes severe complications.

However, severe dehydration is the most common complication, particularly among young children and the elderly, who sometimes need intravenous fluids. No vaccine is available for norovirus.

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