As of November 12, 2025 one additional Washington resident has been added to this outbreak, bringing the total to 10 cases – 9 Washington residents (Chelan 1, Pierce 2, Snohomish 1, Whatcom 5, and King 1) and 1 Oregon resident. All cases report illness onsets before the cheese was recalled on October 24, 2025.
Samples of Twin Sisters Creamery cheese have tested positive for two different STEC strains associated with human cases: E. coli O103 and E. coli O26.
Two Washington residents and one Oregon resident have been infected with E. coli O103. Molecular fingerprinting of the E. coli O103 bacteria from the three cases is extremely similar to the E. coli O103 identified in both the Twin Sisters Creamery Farmhouse and Whatcom Blue cheeses.
Six Washington residents have been infected with E. coli O26. Molecular fingerprinting of the E. coli O26 bacteria from the six cases is extremely similar to the E. coli O26 bacteria identified in the Twin Sister’s Creamery Peppercorn Farmhouse cheese.
| Twin Sisters Creamery brand cheese sample | Where Collected | Where Tested | Shiga |
| Farmhouse variety (opened) | Case’s Home | Commercial Lab | E. coli O103 |
| Whatcom Blue variety | Retail Store | Washington State Department of Agriculture | E. coli O103 |
| Peppercorn Farmhouse variety (unopened) | Case’s Home | Food and Drug Administration | E. coli O26 |
| Farmhouse variety | Retail Store | Washington State Public Health Lab | E. coli NOS* |
*NOS: Not otherwise specified–this strain of Shiga toxin E. coli is not typeable at the Washington State Public Health Lab
All sizes of Whatcom Blue, Farmhouse, Peppercorn and Mustard Seed varieties of aged cheese from Twin Sisters Creamery produced on or after 5/27/2025 are being recalled. Dates listed in recall notices from Twin Sisters Creamery and a distributor, Peterson Company, are the dates the cheese were shipped to retailers and distributors.
- #450 Made on 5/27/2025 – Batch Code 250527B Whatcom Blue
- #452 Made on 6/10/2025 – Batch Code 250610B Whatcom Blue
- #454 Made on 6/18/2025 – Batch Code 250618B Whatcom Blue
- #455 Made on 6/24/2025 – Batch Code 250625B Whatcom Blue
- #451 Made on 6/03/2025 – Batch Code 250603F Farmhouse
- #453 Made on 6/16/2025 – Batch Code 250616B Farmhouse
- #451 Made on 6/03/2025 – Batch Code 250603P Peppercorn
- #453 Made on 6/16/2025 – Batch Code 250616 Mustard Seed
Some cheese products were repackaged by grocery stores and markets, so the original label may not be present. In these instances, the grocery store/market label should say the brand of cheese.
Local, state, and federal partners continue to investigate the source of illness for outbreak-related cases and additional products may be recalled or identified as a possible source of infection in the future.
Company Recall Notice: Twin Sisters Creamery Recalls Whatcom Blue, Farmhouse, Peppercorn, and Mustard Seed Cheese Products Because of Possible Health Risk | FDA
Distributor Recall Notice: Peterson Company Recalls Twin Sisters Creamery Brand Whatcom Blue and Farmhouse Cheese Products Because of Possible Health Risk | FDA