Manitoba health officials and the Agriculture Department have begun a public health investigation to make sure there's no spread of a rare swine flu variant.

The third case of the variant Influenza H-3-N-2 was detected in a person earlier this month in southern Manitoba.

The U.S. Centers for Disease Control and Prevention says the H-3-N-2 variant was first detected in people in 2011, and that it seems to spread more easily to humans from pigs than other swine influenza viruses.

Health officials have said the cases could have coincidentally been discovered because of increased screening taking place because of the COVID-19 pandemic.