SEATTLE (AP) - Ten more probable cases of swine flu were added Monday to Washington state's tally, bringing the total number of probable cases to 45.

So far, the federal Centers for Disease Control and Prevention have not confirmed any of the state's probable cases, state Health Department spokesman Tim Church said.

The state Health Department said 27 of the probable cases are in King County, which includes Seattle; 14 are in Snohomish County and one in Skagit County, both north of Seattle. One is in Pierce County, which includes Tacoma; and two are in Spokane County in northeast Washington.

So far, the state has tested 279 samples out of more than 600 samples collected.

In Skagit County, health officials sent 11 samples to the state, including one of a person who died of pneumonia.

"It is unknown if this person died from H1N1 flu. We are following CDC guidelines to test in this situation," said Peter Browning, director of Skagit County Public Health.

Church said he could not confirm any of the Skagit County spokesman's information.

About 300 cases of swine flu virus have been confirmed in 36 states so far, according to a count by The Associated Press. There has been one death in the United States, a toddler who succumbed to the disease after he was brought to this country from Mexico.

Church said Washington state received test kits from the CDC over the weekend and may be authorized early next week to confirm its own swine flu tests.

"We're testing the system now this week to make sure we get valid results," he said.

In King County, health officials reported six more probable cases swine flu on Monday, with the ages of the people infected ranging from 9 to 54. None of the new cases required hospitalization, said Dr. Jeff Duchin, chief of communicable disease for King County Public Health. Four more probable cases were in Snohomish County.

Duchin reiterated King County's stance that schools closed due to the flu should take steps to reopen. He said that closing schools at this point of the flu's expansion is not practical, and the severity of the outbreak does not call for widespread closures.

He did urge parents to remain vigilant for symptoms connected to swine flu.

Around the Puget Sound region, a handful of schools closed last week due to reports of students falling ill with flu-like symptoms, reports of probable cases of swine flu or students having direct connections to someone believed to have the illness. However, some of the schools have begun preparations to reopen this week, including schools in Seattle, Everett and Federal Way.

Seattle Public Schools announced Monday that the three schools it closed last Friday would reopen Tuesday. They are Madrona K-8, Stevens Elementary and Aki Kurose Middle School. In Snohomish County, Odyssey Elementary reopened Monday, while Jackson Elementary School in Everett was scheduled to reopen Tuesday.

Truckloads of medication and other supplies began arriving in Washington over the weekend as a precaution in case they are needed to treat people with the flu, known as the H1N1 strain.

The supplies are from the federal government's Strategic National Stockpile, and include enough antiviral medication - Tamiflu and Relenza - to treat about 230,000 people, the Health Department said. The medications must be prescribed, the department said.