Salmonellosis in pistachios | The never-ending hatching

The importation of Iranian pistachios has been banned in the country for a month and a half, but the salmonellosis contamination they cause continues. Here’s why.

The first cases of illness linked to the consumption of contaminated Iranian pistachios date back to last spring. Since then, the country, but particularly Quebec, has been hit by this salmonellosis epidemic; recalls of foods made with pistachio or pistachios have multiplied and it doesn’t stop. In the last ten days, there have been seven recalls in Quebec.

This outbreak seems endless, but the very nature of the food in question, pistachio, explains the situation.

First, it must be understood that the nuts may have been imported in bulk and dispersed among several businesses, which makes their traceability more complicated. Pistachio also has a long shelf life.

“You can keep pistachios for a very long time. Months and even years if they have been frozen,” says Lawrence Goodridge, Canada Research Chair in Foodborne Pathogen Dynamics and director of the Canadian Food Safety Research Institute at the University of Guelph.

In addition, the bacteria survives particularly well in dry foods. Like nuts and dried fruits.

This explains why even though we have been talking about this outbreak for months and we have clearly indicated that it is indeed linked to Iranian pistachio, we are still seeing reported cases of illness and recalls.

Entry ban

The Canadian Food Inspection Agency (CFIA) specifies that the recent recalls affect foods made with pistachios that entered the country before September 27, 2025. Because since that date, the CFIA has stopped the importation of pistachios from Iran. Since the start of the outbreak, the Agency and the provincial and municipal authorities responsible for enforcing health on their territory had rather gone one reminder at a time.

This time, we cut the source.

According to Lawrence Goodridge, this probably reflects a more serious problem in Iranian pistachio production overall.

Nuts are foods more likely to suffer this type of contamination, also explains Professor Lawrence Goodridge. By their cultivation in trees where they are in contact with birds, their harvest and their subsequent handling.

According to him, stopping the importation was the safest thing to do until the problem was understood and resolved.

The country has banned the entry of Iranian pistachios for an indefinite period. The CFIA continues its investigation and testing of foods that contain pistachio.

Importers and processors are also asked to prove that they do not use Iranian pistachios. For them, prevention is complex since we do not have a revolutionary process that would allow nuts to be scanned in warehouses or stores to ensure their safety.

We could test them, but the process destroys all the nuts that pass the test. “You can take a sample that comes out negative for salmonella, but there will still be salmonella in the lot,” explains Lawrence Goodridge. In food safety, these tests are considered unreliable. »

No deaths

Consumption of contaminated food can cause salmonellosis, the symptoms of which include fever, headache and vomiting which appear between 6 and 72 hours after consumption. They last on average three to seven days.

In its latest advisory, dated October 21, the Public Health Agency of Canada identified 117 cases of illness in the country linked to this outbreak, including 67 in Quebec, the most affected province. We expect new data any day now. No deaths have been reported.

“Salmonella infections generally do not cause many deaths,” says Lawrence Goodridge. The disease is more worrying for children under 5 years old, pregnant women, people over 60 years old and people with weakened immune systems.