When the outbreak of severe acute respiratory syndrome unfolded, only those with the disease were encouraged to wear the masks to avoid spreading the virus. As a result, wearing the mask became an indicator that a person had the disease, and because of that, no one would wear them, he said. In response, health officials encouraged both well and ill people to wear the masks. That decision, he said, was somewhat effective in curtailing the spread of the disease.

Evans said the federal government, particularly the Centers for Disease Control and Prevention, has not provided guidance on the type of face masks that should be used, the proper use of them and whether local health departments should be stocking a supply.

School officials, he said, also need to know the absentee threshold for the closure of schools.

“We don’t have a threshold for closing schools,” he said. “Is it 30 percent of students and teachers absent, or is it something else?”

Doug Domer, an assistant superintendent in the Joplin R-8 School District, said his district has been concerned about a lack of direction.

"We are basically on our own in determining when to close schools," he said.

Domer said that in the most recent flu season, the absentee rate approached 20 percent. He said it is likely that schools would be closed if the absentee rate for teachers and students reached 30 percent.

“It’s scary to think about,” he said.