Physicians keep an eye out for SARS. (Taking Extra Precautions).

Physicians in the United States have yet to sound the alarm about Severe Acute Respiratory Syndrome, but they're taking extra precautions--just in case.

To date, Dr. Luis Sanz, an ob.gyn. in Chevy Chase, Md., hasn't seen any SARS patients in his practice, but he ordered several boxes of special masks for himself and his staff nonetheless.

The masks "are good for warding off infectious diseases during laser procedures," which generate a lot of smoke, said Dr. Sanz, professor and vice chairman of the Department of Obstetrics and Gynecology with Georgetown University, Washington. Dr. Sanz said he and his nursing staff plan to wear the masks in the event a patient who has just come from Hong Kong, Toronto, China, or Vietnam shows symptoms of the illness.

The key is to prevent the disease from spreading, Dr. Sanz told this newspaper.

So far, these efforts seem to be working. Of the more than 3,500 probable cases of SARS reported worldwide by the World Health Organization, only 220 cases have been reported in the United States. That includes 184 suspected cases and 36 probable cases, according to the Centers for Disease Control and Prevention. There have been no U.S. deaths.

Several factors appear to be influencing the level of vigilance among physicians: geographic location, personal opinions about masks and other protective gear, and actual encounters with suspected SARS cases.

Dr. Jim Martin, director of Christus Santa Rosa Health Care in San Antonio, Tex., hasn't seen one SARS case and isn't too concerned about the epidemic--at least for the moment.