Main Page Content

Monday, June 6

Listeria monocytogenes in relation to Recall of Neilson brand Chocolate Milk

June 6, 2016


The Windsor-Essex County Health Unit is working in collaboration with the Ministry of Health and Long-Term Care and the Canadian Food Inspection Agency (CFIA) on Listeria monocytogenes after food recall warnings of Neilson brand Partly Skimmed Chocolate Milk. For details regarding the recall please refer to the CFIA website.

We would like to take this opportunity to provide local clinicians with a brief update as you may be seeing patients for assessment related to this recall.

Diagnosis and Management of suspected Listeria:

Clinical Presentation: Usually associated with fever, muscle aches, diarrhea, nausea and/or vomiting. Pregnant women, the elderly and immunocompromised are particularly at risk.

  • Listeriosis cannot be clinically diagnosed. 
  • Testing is not recommended for asymptomatic individuals exposed to suspected food sources, including asymptomatic high risk patients.
  • Suspected cases require confirmation with specific laboratory testing.  Please refer to Public Health Ontario(PHO) Labstract as well as the PHO customer service helpline for clinicians @ 1-877-604-4567. 
  • Mean incubation period is not well established. It likely varies depending on the concentration of Listeria in the food and can range from 11 to 70 days (with a mean of 31).
  • Febrile Gastroenteritis: Ingestion of contaminated food can result in a febrile, self-limited gastroenteritis. The incubation period is usually short (range 6 hours to 10 days).This non-invasive illness is self-limiting and requires no therapy in persons in low risk groups.
  • Isolated gastroenteritis: Otherwise healthy persons with suspected listeria gastroenteritis require supportive therapy alone for this self-limiting illness, with no indication for antimicrobial therapy.
  • There is no clear data to guide therapy of isolated gastroenteritis in high risk patients (pregnant, immunocompromised, neonates). If treatment is considered, it should be done in consultation with an infectious diseases physician.  Refer to the full clinical practice guideline here.

All suspected and confirmed cases of Listeria must be reported to the Health Unit immediately. During regular office hours, please call 519-258-2146 ext. 1420 and after hours (weekends and holidays) please call 519-973-4510.