The state's Chief Medical Officer says three new probable cases of swine flu have been identified in Nebraska. The victims live in Madison, Pierce, and Sarpy Counties.

The new cases are in boys between the ages of five and 18. None have hospitalized and are said to be doing well.

A Norfolk middle school and the Madison Public Schools were closed as a precaution Friday because of the probable cases, school administrators said.

School officials at Norfolk Middle School and in the Madison district said they made the decision after learning from health officials that they each had a student who may have the virus. Madison officials said they held no classes Friday because of a possible case at one school and because that student had siblings in another school building. The buildings will be cleaned thoroughly.

“Because of the geographical distance between cases, H1N1 (swine flu) is obviously in Nebraska and spreading,” said Dr. Joann Schaefer, NE Chief Medical Officer. “I expect more cases. H1N1 is probably a virus that is here to stay.”

Thursday, the state confirmed its first case in a California man. It also found two other probable cases.

Dr. Schaeffer says 31 other tests are pending at the Nebraska Public Health Laboratory.