The Canadian Food Inspection Agency (CFIA) is taking further action to contain a salmonella outbreak linked to Iranian pistachios.

The agency is ordering all federally licensed importers and manufacturers to hold and test any pistachios imported before Sept. 27 for salmonella before selling them in Canada.

“This will help protect Canadians from illness and provide consumers with greater reassurance that what they are buying is safe,” CFIA said in a statement.

The CFIA banned Iranian pistachio imports on Sept. 27, and is now conducting targeted testing on products already in Canada.

There are currently 155 confirmed salmonella cases in Canada, and 151 recall alerts, according to the CFIA.

Due to pistachio’s long shelf life, they may still be in Canadian homes, Health Canada, the CFIA and the Public Health Agency of Canada (PHAC) advised in a joint statement.

They say heat may not kill salmonella in pistachios, and they should be thrown out or returned instead of being used in cooking or served.

Only Iranian pistachios are affected by the outbreak, however “it’s safest to avoid the product if the country of origin can’t be confirmed,” according to the three agencies.

They also warn that some pistachio products might not have labels indicating where each ingredient comes from, and that could mean they contain Iranian pistachios.

“Food contaminated with Salmonella may look or smell normal but can still make you sick,” according to the advisory. Children younger than five, pregnant people, adults older than 60, and people with weakened immune system face especially high risks from Salmonella, according to the three agencies. However, “most people who become ill from a Salmonella infection recover fully on their own,” they say.

“Food contaminated with Salmonella may look or smell normal but can still make you sick,” according to the advisory. Children younger than five, pregnant people, adults older than 60, and people with weakened immune systems face especially high risks from salmonella, it adds. However, “most people who become ill from a Salmonella infection recover fully on their own,” they say.

Symptoms of salmonella infection can include chills, fever, nausea, diarrhea, vomiting, stomach cramps, and “a sudden headache,” according to the PHAC. The symptoms generally end within a week, but they can result in long-term health problems or death, it says.