What to Know About the Massive Listeria Outbreak

Correction appended, May 24

An outbreak of the bacteria listeria has caused a frozen food company to recall close to 360 frozen food products.

The recent outbreak of Listeria monocytogenes is just the latest in a series of recalls associated with listeria. The bacteria can cause fever and aches as well as stomach problems and diarrhea. Listeria also grows well in refrigerator temperatures, which is why it can contaminate frozen food as well as deli products like cheese. So far, the outbreak has spanned three states, and two people affected later died. The company, CRF Frozen Foods of Pasco, Wash., has recalled about 358 products that it sold under 42 different brand names.

According to Food Safety News, damaged equipment at the processing plant which has been described by federal investigators as impossible to clean could be a part of the problem.

The outbreak also spans three years, with cases beginning in September 2013. As TIME has previously reported, health authorities are using new technologies to connect cases of illness from different states over many years to ongoing outbreaks as a way to better understand the scope of the contamination.

Various brands of sunflower seeds, salad dressings and trail mix are also being recalled due to listeria contamination unrelated to CRF Frozen Foods.

The bacteria listeria was also behind the 2015 Blue Bell outbreak, which required the company to shut down production and recall its entire ice cream product line. The business is also reportedly under investigation by the Department of Justice. According to the Centers for Disease Control and Prevention (CDC), about 1,600 Americans get sick from Listeria every year, and it is the third leading cause of death from food poisoning.

Correction: The original version of this story incorrectly described the toll of the listeria outbreak. The role listeria played in two deaths remains uncertain, a spokesperson for the CDC said on May 24.