A Thurston County woman is suing a Tacoma burger shop after it served her husband listeria-contaminated milkshakes earlier this year, spreading infections that have since killed him and two others in Washington.
The state Department of Health identified the milkshakes as the source of the outbreak last week, after at least six people — all with compromised immune systems — became sick with bacterial infections between February and July. Three of them, including Charles Roberson, 73, and two others in Pierce County, died after being hospitalized, according to the complaint, filed Monday by Roberson's wife, Linda, in Pierce County Superior Court.
Since the state announced the outbreak last month, public health investigators traced the infections back to ice cream machines at the Tacoma location of Frugals, a family-owned chain in Washington known for its "double drive-thru."
The machines likely weren't cleaned well enough and developed the bacteria over time, said Bill Marler, a Seattle food safety lawyer representing the Robersons.
Linda Roberson had been married to her husband for 45 years when he started feeling sick in May, Marler said this week. The couple lived in Yelm, and had eaten at Frugals several times in March and April.
The following month, Charles Roberson was admitted to Providence St. Peter Hospital in Olympia with numbness and pain in his neck and arms. Within days, he received surgery — related to possible neurological problems, Marler said — and was discharged to a rehabilitation center in Tacoma. While he said details around the procedure are still unclear, Marler believes Roberson's symptoms were likely linked to his listeria infection.
Roberson's condition started to deteriorate again at the rehab center, and he died several weeks later at St. Joseph Medical Center in Tacoma, Marler said.
His spinal fluid was sent to a state laboratory that performs genetic fingerprinting on bacteria samples, where researchers later found Roberson had tested positive for listeria.
The Monday lawsuit argues Roberson's death was wrongful, and that the restaurant is liable and was negligent for the contamination. It requests general and special damages, to be determined in court, in addition to any attorney fees.
Frugals discontinued use of its two milkshake machines in early August and will keep them out of service until public health officials confirm no trace of listeria, according to the state.
The restaurant said in a statement Tuesday afternoon that it received a copy of the complaint late Monday and is still reviewing it.
"We are heartbroken and deeply regret any harm our actions could have caused," Frugals said in a statement. "Food and customer safety has always been our highest priority. We will continue to fully cooperate with and support this ongoing investigation. We are committed to taking any actions necessary to prevent anything like this from happening ever again."
Frugals said it had also shut down its milkshake machines at other locations in Port Angeles, Auburn and Spokane until similar bacterial testing is done.
"What's strange about listeria is that the amount will change over time," said Marler, who has worked on food safety cases for decades, including the Jack in the Box E. coli outbreak that killed four children and infected more than 700 people across four states in the early 1990s.
"If listeria gets into a piece of equipment, like a crack, and there are a couple of times where it's not cleaned enough, then it will have grown," he said. "And some of it might slough off into the ice cream. And then maybe they'll clean it again, but not enough to get rid of the listeria, so it happens again."
He continued, "That's the most likely scenario of why you see so few people sick over an extended period of time."
In this most recent outbreak, those who became infected were in their 40s, 60s and 70s, according to the state. In general, the bacteria spreads from contaminated foods to surfaces and can grow on foods kept in the refrigerator for several days, though high temperatures will kill the bacteria.
Healthy people who are not pregnant often feel short-term symptoms, including fever, muscle aches, nausea, abdominal pain and diarrhea, but some are especially at risk of worse symptoms, the state Department of Health says.
Those over 65, those with weakened immune systems and those who are pregnant are particularly vulnerable to hospitalization or death due to listeria infections. The American Congress of Obstetricians and Gynecologists warns that pregnant people are 10 times more likely to get listeriosis than the general population, and infections can result in miscarriages or cause lifelong problems for their babies.
Outbreaks related to food contamination are "by no means a new phenomenon," the lawsuit says, listing 15 other examples in the U.S. since 1993 that involve sickness spread by ice cream. Included is Washington's 2014 outbreak that hospitalized two people who ate listeria-contaminated Snoqualmie Gourmet Ice Cream.
In this case, health officials might not be able to declare an end to the outbreak until late October, Marler said. Because listeria's incubation period can range between three and 70 days, new infections could still emerge between now and then, he said.
In addition, he encouraged anyone who consumed a milkshake at Frugals between May 29 and Aug. 7 to watch for potential symptoms and reach out to a health care provider with any questions or concerns.
"You normally see a death rate of 25% to 30%," Marler said. "Here, we have 50% — so that means it just happens to be a particularly bad [outbreak], or it means there are more people out there who are sick or will get sick. That's really the mystery of these listeria outbreaks."
Information from The Seattle Times archives was included in this report.