A small Oklahoma school district has ordered all of its students to stay away from classes until December due to an outbreak of mononucleosis, officials said on Thursday.

Woodland Public Schools in Fairfax, about 100 miles northeast of Oklahoma City, said it made the decision so as not to put the nearly 200 students in the district at risk of the contagious disease.

"The closure is due to a high infection frequency of mononucleosis in our community," the school board said.

During the closure, all school buildings will be disinfected to curb the spread of the virus, it said.

The Mayo Clinic said the virus that causes the so-called "kissing disease" is transmitted through saliva, and people can be exposed through a cough or sneeze, or by sharing a glass or food utensils with someone who has "mono."

Symptoms include fatigue, sore throat and fever, it said.