Local medical officer of Health, Dr. Vivien Suttorp, says the disease is cyclical, with outbreaks occurring every three to five years.
She says it's affecting people of all ages.
Suttorp says young children would likely have the worst symptoms and adults more of just a nagging cough that could last several weeks.
The last whooping cough outbreak in the south zone — which is the area south of Calgary and includes Lethbridge and Medicine Hat — was in 2012 and before that in 2009.
Alberta Health Services says whooping cough is extremely contagious and the best way to protect yourself and your family is to get immunized.
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