US Centers for Disease Control and Prevention (CDC) on Tuesday confirmed the first case of A/H1N1 flu in the state of Oklahoma, local officials said, adding four other suspected cases are still being tested in CDC in Atlanta.

"We expected that eventually there would be a confirmed case of H1N1 flu in Oklahoma, so this is no surprise," Governor Brad Henry said in a news release. "The confirmation of a case in the state means citizens should be cautious, but not fearful."

The Governor called on Oklahomans to take commonsense measures to avoid getting the virus, and to see a doctor if they experience flu-like symptoms. "Oklahoma's healthcare and public safety communities have the resources and personnel in place to handle any challenges posed by H1N1 flu." he declared.

The confirmed case involved a Pontotoc County woman who recently returned from Mexico. The state health officials disclosed the woman is married and her spouse has not shown any symptoms of swine flu.

The patient did not require hospitalization and is expected to make a full recovery, they said.

The CDC has reported 403 cases of the swine flu in 38 US states as of early Tuesday. Oklahoma's case had not yet been included in that count.

A number of Pontotoc County schools reported they are preparing for A/H1N1 flu just as they prepare for a typical flu season.

"Right now, we're sending out a letter that lists the symptoms. We're cleaning desks and doorknobs, just as we do during the seasonal flu," said Pat Harrison, superintendent of Ada Public Schools.

In an afternoon press conference, CDC Acting Director Richard Besser said the agency has changed its previous advice to schools to consider closure in the event of a confirmed A/H1N1 flu case. Since most US cases are not severe, school closure is not necessary and can be very disruptive, he said.

"The points about personal preparedness and personal responsibility are critical," he claimed, including keeping sick students home from school for at least seven days.