Public Health Notice: Outbreak of norovirus and gastrointestinal illnesses linked to spot prawns

June 23, 2022 – Final update

This notice has been updated to reflect that the outbreak appears to be over and the outbreak investigation has been closed.

spot prawns

On this page

Why you should take note

The Public Health Agency of Canada (PHAC) collaborated with provincial public health partners, the Canadian Food Inspection Agency (CFIA) and Health Canada to investigate an outbreak of norovirus and gastrointestinal illnesses involving four provinces: British Columbia, Alberta, Manitoba, and Ontario. The outbreak appears to be over and the investigation has been closed.

Investigation findings identified consumption of spot prawns as the source of the outbreak. All of the individuals who became ill reported eating spot prawns before their illnesses occurred.

The CFIA issued food recall warnings for several lot codes of spot prawns that were associated with the illnesses under investigation. Links to each food recall associated with this investigation can be found at the end of this public health notice.

Investigation Summary

In total, 60 cases of norovirus and gastrointestinal illness were reported in the following provinces: British Columbia (18), Alberta (12), Manitoba (19), and Ontario (11). Individuals became sick between mid-May and late-May 2022, and no deaths were reported. Although not all cases of illness were tested, laboratory testing had confirmed the presence of norovirus infection.

The CFIA issued food recall warnings for several lot codes of spot prawns that were associated with the illnesses under investigation. For more information on the recalled products, please consult the Government of Canada's Recalls and Safety Alerts website.

Who is most at risk

Acute gastrointestinal illnesses such as norovirus are common in North America and are very contagious, affecting all age groups. However, pregnant women, people with compromised immune systems, young children and the elderly are at risk for developing more serious complications, like dehydration.

What you should do to protect your health

Spot prawns contaminated with noroviruses may look, smell and taste normal. The following safe food-handling practices will reduce your risk of getting sick:

  • Do not eat, use, sell, or serve the recalled spot prawns. Check to see if you have the recalled spot prawns at home. If you do, throw them out and wash your hands.
  • Avoid eating raw or undercooked spot prawns.
  • Eat spot prawns right away after cooking and refrigerate leftovers.
  • Always keep raw and cooked spot prawns separate to avoid cross-contamination.
  • Do not use the same plate or utensils for raw and cooked spot prawns.
  • Wash your hands well with soap before and after handling any food.
  • Be sure to clean and sanitize cutting boards, counters, knives and other utensils after preparing raw foods.

Noroviruses can be transmitted by ill individuals. Cleaning and disinfecting practices are the key to preventing further illnesses in your home.

  • Thoroughly clean contaminated surfaces, especially after an episode of illness.
  • After vomiting or diarrhea, immediately remove and wash clothing or linens that may be contaminated with the virus (use hot water and soap).
  • If you have been diagnosed with norovirus illness or any other gastrointestinal illness, do not prepare food or pour drinks for other people while you have symptoms, and for the first 48 hours after you recover.

Symptoms

People with norovirus illness usually develop symptoms of gastroenteritis within 24 to 48 hours, but symptoms can start as early as 12 hours after exposure. The illness often begins suddenly. Even after having the illness, you can still become re-infected by norovirus.

The main symptoms of norovirus illness are:

  • diarrhea
  • vomiting (children usually experience more vomiting than adults)
  • nausea
  • stomach cramps

Other symptoms may include:

  • low-grade fever
  • headache
  • chills
  • muscle aches
  • fatigue (a general sense of tiredness)

Most people feel better within one or two days, with symptoms resolving on their own, and experience no long-term health effects. As with any illness causing diarrhea or vomiting, people who are ill should drink plenty of liquids to replace lost body fluids and prevent dehydration. In severe cases, patients may need to be hospitalized and given fluids intravenously. If you have severe symptoms of norovirus, consult your healthcare provider.

What the Government of Canada is doing

The Government of Canada is committed to food safety.

The Public Health Agency of Canada leads the human health investigation of an outbreak and is in regular contact with its federal and provincial partners to monitor and take collaborative steps to address outbreaks.

Health Canada provides food-related health risk assessments to determine whether the presence of a certain substance or microorganism poses a health risk to consumers.

The Canadian Food Inspection Agency conducts food safety investigations into the possible food source of an outbreak.

Epidemiological information

Figure 1 is an epidemiological curve for this outbreak, which shows the numbers of new cases by week. Outbreak investigators use this information to show when illnesses begin, when they peak, and when they trail off. It can take several weeks from the time a person becomes ill to when the illness is reported and linked to the outbreak. Data are available for 60 cases.

Figure 1: Reported number of cases of norovirus or acute gastrointestinal illness associated with exposures to spot prawns, by week

figure 1

Figure 1: Text equivalent
Table 1 – Reported number of cases of norovirus or acute gastrointestinal illness associated with exposures to spot prawns, by week
Week of symptom onset Number of cases
2022-05-01 0
2022-05-08 19
2022-05-15 9
2022-05-22 32
2022-05-29 0
2022-06-05 0
2022-06-12 0
2022-06-19 0

Additional information

Investigation history

Public Health Notice Update: June 10, 2022

The Public Health Agency of Canada (PHAC) is collaborating with provincial public health partners, the Canadian Food Inspection Agency (CFIA) and Health Canada to investigate an outbreak of norovirus and gastrointestinal illnesses involving four provinces: British Columbia, Alberta, Manitoba, and Ontario.

Investigation findings have identified consumption of spot prawns as the source of the outbreak. All of the individuals who became ill reported eating spot prawns before their illnesses occurred. More information is needed to determine how the spot prawns became contaminated with norovirus.

The CFIA has issued food recall warnings for several lot codes of spot prawns that are associated with the illnesses under investigation. Links to each food recall associated with this investigation can be found at the end of this public health notice. The recalled products have been sold in British Columbia, Alberta, Manitoba, and Ontario, and may have been distributed in other provinces and territories. The CFIA is continuing its food safety investigation, which may lead to the recall of other products. If other products are recalled, the CFIA will notify the public through updated food recall warnings.

Do not eat, use, sell or serve the recalled spot prawns. Check to see if you have the recalled spot prawns at home. If you do, throw them out and wash your hands.

The outbreak investigation is ongoing and additional actions to protect public health will be taken as needed. The public health notice will be updated as the investigation evolves.

Investigation Summary

As of June 10, 2022, there have been 60 cases of norovirus and gastrointestinal illness reported in the following provinces: British Columbia (18), Alberta (12), Manitoba (19), and Ontario (11). Individuals became sick between mid-May and late-May 2022, and no deaths have been reported. Although not all cases of illness have been tested, laboratory testing has confirmed the presence of norovirus infection.

The CFIA is continuing its food safety investigation into the spot prawns associated with the illnesses under investigation. The CFIA has issued food recall warnings for several lot codes of spot prawns that are associated with the illnesses under investigation. Links to each food recall associated with this investigation can be found at the end of this public health notice.

If other products are recalled through the CFIA food safety investigation, the CFIA will notify the public through updated food recall warnings. For more information on the recalled products, please consult the Government of Canada's Recalls and Safety Alerts website.

Public Health Notice: June 1, 2022

Why you should take note

The Public Health Agency of Canada (PHAC) is collaborating with provincial public health partners, the Canadian Food Inspection Agency (CFIA) and Health Canada to investigate an outbreak of norovirus and gastrointestinal illnesses involving four provinces: British Columbia, Alberta, Manitoba, and Ontario.

Investigation findings have identified consumption of spot prawns as the source of the outbreak. All of the individuals who became ill reported eating spot prawns before their illnesses occurred. More information is needed to determine how the spot prawns became contaminated with norovirus.

On May 31, 2022, the CFIA issued a food recall warning for several lot codes of live spot prawns that are associated with the illnesses under investigation. The recalled products have been sold in British Columbia, Alberta, Manitoba, and Ontario, and may have been distributed in other provinces and territories. The CFIA is continuing its food safety investigation, which may lead to the recall of other products. If other products are recalled, the CFIA will notify the public through updated food recall warnings.

Do not eat, use, sell or serve the recalled spot prawns. Check to see if you have the recalled spot prawns at home. If you do, throw them out and wash your hands.

The outbreak investigation is ongoing and additional actions to protect public health will be taken as needed. The public health notice will be updated as the investigation evolves.

Investigation summary

As of June 1, 2022, there have been 48 cases of norovirus and gastrointestinal illness reported in the following provinces: British Columbia (11), Alberta (12), Manitoba (19), and Ontario (6). Individuals became sick between mid-May and late-May 2022, and no deaths have been reported. Although not all cases of illness have been tested, laboratory testing has confirmed the presence of a norovirus infection.

The CFIA is continuing its food safety investigation into the spot prawns associated with the illnesses under investigation. A food recall was issued on May 31, 2022 for several lot codes of live spot prawns that are associated with the illnesses under investigation. For more information on the recalled products, please consult the Government of Canada's Recalls and Safety Alerts website. If other products are recalled through the CFIA food safety investigation, the CFIA will notify the public through updated food recall warnings.

Media Contact

Public Health Agency of Canada
Media Relations
Telephone: 613-957-2983
Email: [email protected]

Public Inquiries

Call toll-free: 1-866-225-0709
Email: [email protected]

Page details

Date modified: