Three die of listeria in western WA, source of illnesses still unknown

Three out of five people hospitalized for listeria infections in Pierce and Thurston counties have died, according to information from the Washington Department of Health. 

DOH is still investigating the source of the listeria cases. Patients became ill between February 27 and June 30th of this year.

All five patients were over 60 and had compromised immune systems. 

People at a higher risk for listeriosis include people who are pregnant, people who are 65 years or older and those with weakened immune systems.

Listeria is a bacteria often found in unpasteurized dairy and meat products and can grow in foods kept in a refrigerator for several days. It can easily be killed by heating foods to 165 degrees fahrenheit.

DOH also warns unheated sliced deli meats and cheeses may also pose a listeria risk.