State officials report they have not found E. coli in samples tested in relation to an outbreak linked to Pure Eire Dairy in Washington.

Fifteen people are confirmed sick, including nine who have been hospitalized. Four children have developed the potentially deadly kidney complication known as hemolytic uremic syndrome (HUS). Most patients reported eating organic yogurt from the local dairy.

A spokesman from the Washington Department of Agriculture told Food Safety News today that the investigation is ongoing and more testing is likely.

“It’s important to note that testing samples does not always reveal the presence of E. coli, one reason being that sample sizes are small relative to product volume,” according to the department spokesman. 

“In addition, the batches tested were from available product, and not necessarily the product that has made people sick. The absence of E. coli does not mean the product was free of E. coli, only that the bacteria was not detected.”

The department collected 40 environmental samples from the dairy’s processing facility and 15 samples of its pasteurized milk, The dairy also produces raw, unpasteurized milk for sale to the public. A dozen samples of yogurt previously were tested from retail outlets, but did not show E. coli contamination.

The most recent samples were tested at WSDA’s Food Safety and Consumer Services Laboratory.

According to state officials the dairy is still not producing products for sale. State investigators are continuing their work, which could  involve collecting additional samples and gathering more information about the dairy’s processes and operation, according to the agriculture department spokesman.

The dairy recalled all of its yogurt — including PCC Markets brand and Pure Eire brand — earlier this month after sick people reported eating the PCC brand.

About E. coli infections
Anyone who has eaten any of the implicated products and developed symptoms of E. coli infection should seek medical attention and tell their doctor about their possible exposure to the bacteria. Specific tests are required to diagnose the infections, which can mimic other illnesses.

The symptoms of E. coli infections vary for each person but often include severe stomach cramps and diarrhea, which is often bloody. Some patients may also have a fever. Most patients recover within five to seven days. Others can develop severe or life-threatening symptoms and complications, according to the Centers for Disease Control and Prevention (CDC).

About 5 to 10 percent of those diagnosed with E. coli infections develop a potentially life-threatening kidney failure complication, known as a hemolytic uremic syndrome (HUS). Symptoms of HUS include fever, abdominal pain, feeling very tired, decreased frequency of urination, small unexplained bruises or bleeding, and pallor.

Many people with HUS recover within a few weeks, but some suffer permanent injuries or death. This condition can occur among people of any age but is most common in children younger than five years old because of their immature immune systems, older adults because of deteriorating immune systems, and people with compromised immune systems such as cancer patients.

People who experience HUS symptoms should immediately seek emergency medical care. People with HUS will likely be hospitalized because the condition can cause other serious and ongoing problems such as hypertension, chronic kidney disease, brain damage, and neurologic problems.

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