Listeriosis is a disease caused by the bacteria Listeria monocytogenes. Symptoms of listeriosis include vomiting, nausea, diarrhea, cramps, severe headache, constipation and persistent fever. This uncommon disease can have serious consequences for high risk groups such as pregnant women and their fetuses, the elderly and very young. Listeriosis is spread by consuming contaminated food or drinks. Soft cheeses, deli meats and unpasteurized milk are examples of commonly contaminated foods. For more information, see the health unit’s fact sheet on listeriosis.
The following graph shows the number of listeriosis cases in Simcoe Muskoka between 2000 and 2015. There have been between zero and five cases in Simcoe Muskoka every year since 2000. In 2015, there were three listeriosis case reported in Simcoe Muskoka.
The following graph shows the incidence rate of listeriosis in Simcoe Muskoka and Ontario between 2000 and 2015. The incidence rate in Simcoe Muskoka is comparable to the Ontario rate and both have remained low during this time period. In 2015, the incidence rate for listeriosis for Simcoe Muskoka was 0.55 cases per 100,000 population and the Ontario rate was 0.47 cases per 100,000 population. The Simcoe Muskoka rate has some variability which means that there are peaks and valleys and it is difficult to determine whether an increase is significant or whether it is within the expected range for this disease in these populations.
In 2008, there was a national increase in listeriosis cases when a national outbreak associated with deli meats lead to the recall of more than 200 products.
There are many factors that influence how many cases are reported to the Health Unit, as explained on the Infectious Diseases page.