Several recent cases of salmonella have been linked to consumption of Papa Murphy’s raw cookie dough, the Oregon Health Authority announced Tuesday.

Epidemiologists have investigated four cases of identical strains of salmonella bacteria, with symptoms beginning between April 1 and April 21. There have been no deaths or hospitalizations. The afflicted people range in age from 20 to 57.

Customers are advised to discard raw s’mores bars or cookie dough from Papa Murphy’s and wash their hands afterwards. If they feel ill after consuming raw cookie dough, they should tell a health provider.

The Washington State Department of Health has also discovered identical strains of salmonella bacteria.

The Oregon and Washington health authorities are working with the Oregon Department of Agriculture, and the Centers for Disease Control and Prevention to investigate the source of the bacteria.