According to the Washington State Department of Health, six Washington residents (five from Pierce County and one from Thurston County) developed severe illness due to infection with Listeria bacteria (listeriosis). Three of the individuals died. Genetic fingerprinting (whole genome sequencing) of the bacteria indicated that the same food was likely responsible for making all six people sick.

Two of the people infected with listeriosis reported consuming milkshakes from Frugals restaurant at 10727 Pacific Ave. S., Tacoma, WA, 98444 prior to becoming sick. Because milkshakes and ice cream have caused listeria outbreaks in the past, the Tacoma-Pierce County Health Department collected milkshake samples from the restaurant on August 8, 2023. On August 18, 2023, all flavors of the milkshakes were found to be contaminated with the same strain of Listeria that caused the outbreak.

The restaurant discontinued use of its two milkshake machines on August 8. The milkshake machines will be kept out of service until the Tacoma-Pierce County Health Department determines they are free of Listeria contamination and no longer pose a danger to the public.