The flu season is keeping substitute teachers busy this year.

The Yankton school district has been building a larger-than-normal pool of substitute teacher candidates, as students aren't the only ones being kept from classes because of the H1N1 and seasonal flu viruses.

Yankton superintendent Joseph Gertsema says no one knows how the flu viruses are going to affect schools, so everyone is preparing for the worst yet hoping for the best.

Substitute teachers are used almost every day of a typical school year, and that number has the potential to increase given the illnesses circulating the area.

Gertsema says the district is keeping in contact with the education departments at Mount Marty College and the University of South Dakota. He says those finishing up student teaching assignments and graduating at the semester's end could lend a hand.

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