By: Candess Zona-Mendola

A mystery outbreak of Listeria illnesses was announced this week with 24 cases in 13 states. The health agencies investigating the outbreak, which currently has 22 hospitalizations and two deaths, have not identified a source at this time. However, it is quite interesting that this US outbreak comes close on the heels of another concerning Listeria outbreak in Canada involving cooked diced chicken.

The CDC reports that, “The Public Health Agency of Canada is also investigating an outbreak of Listeria monocytogenes infections in several Canadian provinces linked to cooked diced chicken.  Whole genome sequencing showed that the type of Listeria making people sick in Canada is closely related genetically to the Listeria making people sick in the United States.”

When multiple Listeria samples are “closely genetically related” by whole genome sequencing, it is a strong indicator that they may share a common food source.  It is highly likely that these two outbreaks are linked and are actually just one big Chicken Listeria Outbreak. As of now, the Public Health Agency of Canada health officials has linked their outbreak to and issued food recalls for: Rosemount brand cooked diced chicken meat, Reuven International Ltd brand Natural Proportion Cooked Chicken Meat (Diced), and Sysco brand Natural Proportions Cooked Shredded Chicken. Whether these brands made it to the US or are part of a bigger supplier up the supply chain has yet to be announced.

This would not be the first time the US and Canada were part of the same outbreak, which is what we saw in the Romaine Lettuce E coli outbreaks last year.