In the wake of swine flu being diagnosed in San Diego County and four probable cases appearing in Riverside County, health care officials Wednesday called for people to stay calm and practice the usual precautions they would take in a typical influenza season.

"If you are sick, don't go to work or school or travel," said Tom Christensen, spokesman for the San Diego County Health & Human Services Agency.

Frequent hand washing and covering your nose and mouth when coughing and sneezing were among the recommendations suggested health officials in both counties.

Running out and buying masks to prevent the spread of the virus was not.

"Masks in a general public setting are not being recommended for use," said Sarah Mack, a spokeswoman for the Riverside County Health Department. "Worn for a long period, masks become hot and wet and people just take them off."

A somewhat similar recommendation came from the California Department of Public Health.

"As far as wearing masks, we don't feel they are that effective if a person is not sick," said Tony Cava, a department spokesman. "It's a call people can make on their own."

It wasn't masks people sought Wednesday at the Vail Ranch Pharmacy in Temecula, but the antiviral prescription drugs Tamiflu and Relenza, which the Centers for Disease Control has recommended for the treatment or prevention of infection from swine influenza viruses, according to that agency's Web site.

"We haven't had anyone coming in to buy masks," said pharmacist Basil Maqbool.

The pharmacy couldn't get Tamiflu until Wednesday and has been unable to get Relenza at all, he said.

Tamiflu is the brand name of the drug Oseltamivir, and Relenza the brand name of Zanamivir. The two are among four influenza antiviral drugs approved for use in the United States, according to the CDC. The other two drugs do not work against swine influenza viruses.

"We got the Tamiflu in this morning and it's already gone," Maqbool said. "We had a woman drive all the way here from Riverside because she said this was the only place she could find it."

Orders for at least 10 adult strength and 10 children's strength prescriptions for those drugs are on hold at the pharmacy.

"We're hoping to get more (on Thursday)," Maqbool said.

The Temecula pharmacy's experience seems to contradict county information.

Mack said Riverside County's Pharmacy Emergency Response Team has been monitoring the stock of viral medication and the information they've received is that supplies are available.

County officials recommended people experiencing mild flu-like symptoms should stay at home and manage their care there, Mack said.

If symptoms become more severe, people are urged to contact their doctor.

"You should have a conversation with your health care provider about what the options are," Mack said.

Contact staff writer John Hunneman at (951) 676-4315, Ext. 2603, or hunneman@californian.com.

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