Pertussis, also known as whooping cough, is a disease caused by the bacteria Bordetella pertussis. Symptoms of pertussis include sneezing, runny nose, low grade fever and coughing. Coughing may occur in violent spells followed by an intake of breath that sounds like a "whoop". For more information, see the health unit's fact sheet on pertussis.
Pertussis can be prevented by a vaccine. In 2004, Ontario began funding a pertussis booster for 14-18 year olds because the protection provided by the pertussis vaccine in early childhood decreases by adolescence. In 2011, Ontario also began funding a pertussis booster for adults (19-64 years old) who have not received their adolescent booster to ensure that adults are protected and do not pass it on to young children, who are at most risk of serious complications. For more information on the vaccine, please see the health unit’s fact sheet on pertussis vaccine.
The following graph shows the number of pertussis cases in Simcoe Muskoka between 2000 and 2015. There have been between 1 and 41 cases of pertussis in Simcoe Muskoka every year since 2000. In 2015, 16 cases of pertussis were reported in Simcoe Muskoka.
The following graph shows the incidence rate of pertussis in Simcoe Muskoka and Ontario between 2000 and 2015. In 2015, the pertussis incidence rate in Simcoe Muskoka was 2.9 cases per 100,000 population and the Ontario rate was 5.1 cases per 100,000 population. There is high variability in both the Simcoe Muskoka and Ontario rates, which means that there are many 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. Pertussis incidence generally peaks every 5 years.
In 2004, a more sensitive test for pertussis was introduced in Ontario, which may have caused an increase in the percentage of cases that tested positive starting that year.
There are many factors that influence how many cases are reported to the health unit, as explained on the Infectious Diseases page.
Provincial definitions classify cases as confirmed, probable or suspect based on clinical and/or laboratory diagnostic criteria. The provincial case definition for pertussis changed in April 2009 to include a definition for probable cases whereas before there was no such classification. The definitions of confirmed and probable cases from 2009 onwards are comparable to confirmed cases before 2009.
Pertussis follows a cyclical incidence pattern with peaks observed every three to five years.