There have been 20 confirmed cases of swine flu in the Los Angeles County Jail system, with most of the infected inmates housed at the Pitchess Detention Center in Castaic, the Sheriff's Department reported today.

Inmates diagnosed with the virus have been placed in isolation, with restricted visits, and will be tested and monitored over a seven-day period, said sheriff's spokesman Steve Whitmore. Two inmates have been taken to outside hospitals for treatment and were "doing OK."

"It's not considered by any stretch an epidemic," Whitmore said. The first case was reported about weeks ago at the downtown Twin Towers jail.

"People are getting better and many are being cleared," Whitmore said. "We're cautiously optimistic that it's being contained, but the flu is the flu."

Jail officials believe that inmate trusties were infected with the virus outside the jail and brought it back in, Whitmore said. About a month ago, jail supervisors isolated about two dozen inmates who fell ill with the flu at the Pitchess South Facility, but it was not H1N1.

No jail staff has been infected, Whitmore said. A total of 190 inmates have been isolated in the current outbreak, and sheriff's officials said they are sanitizing cells of the infected and testing their cellmates.

"They are doing everything necessary to ensure that it will not return," Whitmore said.

-- Molly Hennessy-Fiske and Andrew Blankstein