Executives at seafood processing giant Milarex are alarmed at a doubling of positive cases of listeria being found in salmon raw material products in testing carried out by the company.

Milarex saw a near doubling of listeria discoveries in 2021 with 4 percent of tests on raw materials revealing the presence of the bacteria, which can be harmful to pregnant women, newborns, adults aged 65 or older and people with weakened immune systems.

In 2020, the company saw rates of listeria on salmon purchases fall to 2.1