Owners of snakes and lizards should take precautions when feeding them frozen rodents, which may be contaminated with salmonella, the Public Health Agency of Canada says.

The agency says seven cases of human illness have been reported in Canada between April and August caused by a strain of salmonella linked to frozen rodents. The agency did not identify any particular producer.

Food for cats and dog can also carry salmonella.

The agency recommends:

• Always washing hands thoroughly with soap and water after feeding or handling or cleaning up after pet reptiles and their food products.
• Cleaning surfaces that come into contact with reptiles or their food.
• Sealing frozen reptile food products in a plastic bag and place in a covered garbage can.

The Public Health Agency said it is investigating with provincial and territorial counterparts whether this salmonella outbreak is associated with a similar illness in the U.S. and if a product implicated in a U.S. outbreak was distributed in Canada.

Symptoms of a salmonella infection, called salmonellosis, typically start within six to 72 hours of exposure to contaminated food. Symptoms include diarrhea, fever, abdominal cramps, nausea, vomiting, chills and headache and usually last four to seven days.

In healthy people, salmonellosis often clears up without treatment. People who experience severe symptoms, or who have underlying medical conditions, should contact their health-care provider if they suspect they have a salmonella infection.