SAN DIEGO -- Six teachers at a private school in Mira Mesa tested negative for swine flu and the campus is slated to reopen for classes on Wednesday, county health officials said Tuesday.

Christ the Cornerstone Academy was closed Tuesday as a precautionary measure while tests were conducted to see if the six teachers suspected of having swine flu actually contracted the disease, said Dr. Wilma Wooten, San Diego County's public health officer.

The teachers were believed to have been exposed to the virus by a student at the school who tested positive for it, according to Wooten.

With the teachers testing negative, the school was cleared to reopen.

"We thought it was prudent to obtain specimens on individuals reporting illness and close the school until we got the tests," Wooten said. "We are happy to say the tests came back today negative and the school will be allowed to reopen tomorrow or at the discretion of the school administration."

Meanwhile, Wooten said there were still five confirmed cases of swine flu in San Diego County, along with three "probable" cases.

The two of the unconfirmed cases involve relatives of a confirmed case of swine flu, Wooten said, adding that confirmation was pending from the U.S. Centers for Disease Control and Prevention.

"All San Diego illnesses have been mild and the individuals have all recovered," Wooten said.

According to Wooten, guidelines from the CDC mandate that schools close for a period of seven days after just a single case of swine flu has been confirmed.

Wooten said if residents are sick, they should stay home from work or school.

Enough doses of anti-viral medications for 50,000 people have been delivered to the San Diego region from a strategic national stockpile, Wooten said.

Gov. Arnold Schwarzenegger's declaration of a state of emergency Tuesday will also free up resources for local jurisdictions, Wooten said.

Swine flu is usually spread from pigs to humans but health officials worldwide are concerned about the prospect of a pandemic because the current strain of the disease is being spread from humans to humans.

The disease is most prevalent in Mexico, where about 2,000 people have developed influenza and about 150 are believed to have died from the virus. Only 26 of them were confirmed as of this morning to have been swine flu sufferers.

There were 68 confirmed cases in the United States. No U.S. fatalities have been reported.

Elsewhere, cases of swine flu have been confirmed in Canada, Scotland and Spain. Unconfirmed cases have also been reported in New Zealand, France and Israel.

Because the outbreak appears to be linked to Mexico, the U.S. Customs and Border Protection in San Diego said Monday that people who appeared sick at local border crossings were being taken to a secondary inspection area for further evaluation.