More than 500 people have gotten sick from norovirus in the Tacoma-WA area. Public health officials say two El Toro restaurants in the area are linked to the outbreak. Photo illustration

The number of people sick in a Tacoma, WA-area norovirus outbreak hit 542 this week, increasing by almost 40 percent since Jan. 11.

Norovirus has been confirmed by Tacoma-Pierce County Health Department officials as the pathogen responsible for the outbreak. Of the 542 reported victims, 520 ate at an El Toro restaurant in Tacoma. Another 22 people are possibly sick after eating at the chain’s restaurant in a nearby suburb, the department reported Thursday.

The number of sick patrons is up from 391, reported Jan. 11 in the health department’s weekly update. However, county officials reported in the Jan. 18 update that the situation appears to have peaked and they will not continue regular updates.

When it started
The health department began receiving reports of possible food poisoning on Jan. 5 from customers in separate households who had eaten at the Tacoma restaurant between Dec. 31 and Jan. 2. Earlier this week, the department learned of suspected cases at the University Place site from customers who had eaten there this past weekend.

The customers experienced one or two days of symptoms, including vomiting and diarrhea, about 24 to 36 hours after eating at the restaurant, the health department reported.

The implicated restaurants are the at 5716 N. 26th St. in Tacoma and at 3820 Bridgeport Way West in University Place.

A lab test identified the norovirus as the culprit in the Tacoma outbreak, but tests are pending for the University Place illnesses, according to the health department.

Both restaurants were closed for at least one day for thorough cleaning and sanitation, the department said. They have since reopened.

How it spread
Norovirus is highly contagious and is more common during cold weather. Environmental Health Supervisor Christina Sherman from the department’s Food and Community Safety Program said outbreaks can last a few days, a few weeks or a few months.

Many cases of norovirus go unreported, but people who get sick at a restaurant can go home and infect family members and others during the incubation period. The average length for that period is 12 to 48 hours.

People likely get norovirus an average of five times in their lives but don’t necessarily realize what it is — and they probably don’t report it, Sherman said in an interview on the Health Department’s website.

The Tacoma exposure period had gone on for eight days before the department got word that people were sick, she said.

The El Toro restaurants had each failed a routine inspection but passed on follow-up visits, the department said. But even restaurants that pass muster can go on to have foodborne illness outbreaks.

What to do
The virus can live on surfaces for as long as two weeks, so hard surfaces must be sanitized with bleach and water. Cloth and other surfaces must be heated and/or steamed, the health department said.

And, it’s critically important that food workers wash their hands often, not touch ready-to-eat food with their bare hands and stay home when they’re sick.

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