Research – Listeria monocytogenes Associated with Pasteurised Chocolate Milk, Ontario, Canada 2015- 2016

CDC Listeria cdc

n an investigation of a listeriosis outbreak in Ontario, Canada, during November 2015–June 2016, pasteurised chocolate milk was identified as the source. Because listeriosis outbreaks associated with pasteurised milk are rare in North America, these findings highlight that dairy products can be contaminated after pasteurisation.

Listeria monocytogenes is a formidable pathogen acquired primarily through contaminated food. Invasive listeriosis is a reportable disease in Ontario, Canada; ≈50 case-patients (0.4 cases/100,000 persons) have been reported annually since 2005 (1). Recent outbreaks of listeriosis in North America have been associated with delicatessen meats, soft cheeses, raw produce, and unpasteurised dairy products (24). However, listeriosis outbreaks linked to pasteurised fluid milk are rare.

A study in the United States reviewed 83 fluid milk–associated disease outbreaks during 1990–2006; however, only 1 outbreak was attributed to L. monocytogenes (5). We report an outbreak of listeriosis associated with pasteurised chocolate milk in Ontario, Canada.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s