Colorado health officials say listeria killed two people in the state last month as the number of cases spiked. 

An epidemiologist for the state health department, Alicia Cronquist, said a total of nine people were sickened by listeria during August, compared with two in a typical month. Seven of the cases were reported this week.

The state hasn’t released any details yet about where the victims are from but Cronquist said all are adults, most of them older.

Cronquist says it’s not known if any of the infections are related to a smoked salmon recall by Chicago-based Vita Food Products. She says officials are talking to those who were sickened and their relatives to find out about their recent activities, including what they’ve been eating.