Giardiasis incidence rates were significantly lower in the NWHU in 2009 and 2013 compared with Ontario as a whole, and about equal in between those years. The rapid fluctuations seen in the graph below are likely to due to small case numbers in the region. The rate remained relatively stable in Ontario from 2009 to 2013, ranging between 10.5 and 12.5 cases per 100,000 per year.
Approximately two thirds of cases over this time occurred in males (67.7%) and almost half of all cases were in the mid-range 20 to 44 years of age group (45.2%).
Giardiasis incidence rates, NWHU and Ontario, 2009-2013
Giardiasis case counts by sex, NWHU, 2009-2013
Giardiasis case counts by age group, NWHU, 2009-2013