Approximately 15,000 attendees at a two-day JAMFEST concert at HP Pavilion in San Jose are in a literal "race with death" to be treated for a deadly, highly contagious pneumonic plague.

That is the crux of a statewide disaster simulation this morning called the Golden Guardians. The Palo Alto scenario was that bioterrorists had released airborne pneumonic-plague bacteria sometime during the JAMFEST concert Nov. 13 and 14 using large canisters resembling welding tanks.

Police and medical officials taking part in the one-day exercise said they practiced using every method at their disposal to warn the public of the deadly threat of infection.

Volunteers from throughout Palo Alto took part by role-playing everything from nosy reporters and hysterical mothers in search of their children to City Council candidates in search of publicity for their political campaigns.

At an emergency-volunteer base at Cubberley Community Center, volunteers offered their help. At a medical and triage center at Mitchell Park, blue M&Ms were supplied as "antibiotics" against the disease to volunteers pretending to be victims.

The purpose of the exercise was to test how well agencies and the public would communicate with one another in a disaster.

Former Palo Alto Mayor Vic Ojakian, participating as a volunteer, told key city administrators that the morning exercise revealed the need to "do more coordination and communication" among responders to the emergency.

"That's the key piece -- communication," Ojakian said.

Councilman Jack Morton agreed and cited an instance in which council members showed up at an emergency center and the person in charge "didn't know what to do with us, and we didn't know what to do with him."

The full scope of the emergency was revealed at a midday press conference at City Hall when Palo Alto Police Chief Lynne Johnson and volunteer Paul Gilman, posing as a physician from Stanford Medical Center, outlined the severe danger people faced.

Untreated pneumonic plague could be fatal in more than 80 percent of the cases, Gilman said. Even if treated within the first few days, the survival rate would be 95 percent -- meaning 5 percent of concert-goers would have died.

In addition, those at the concert could easily have infected others before even knowing they were sick, Gilman said.

Gilman said after the conference that he didn't know the true statistics. But Red Cross officials at the press conference said Gilman's estimate that one person could infect five to eight bystanders was close to accurate.

The annual drill has been conducted by the State of California Governor's Office of Homeland Security since 2004.