| LOS ANGELES
LOS ANGELES California has confirmed 11 cases of the swine flu and expects that number to rise, state health officials said on Monday, as at least two schools closed after students became ill.
Two "probable" infections were also identified on Monday as authorities said it was too late to contain the spread.
"The word 'containment' is really inappropriate or ... unneeded at this time. It's too late. The swine flu is here," said Dr. Bonnie Sorensen, chief deputy director of the California Department of Public Health.
Among the new cases was a teenage boy at St Mel Catholic School in Fair Oaks, a Sacramento suburb. He is the first person in Northern California known to be sick with the disease that has killed 149 people in Mexico.
Three other students, at least one of whom had recently traveled to Mexico, were being tested at St Mel, which has about 270 students. Administrators there canceled classes until at least Thursday.
A school in the Los Angeles suburb of Claremont also canceled classes through Thursday, saying that a girl and her mother developed flu-like symptoms after a trip to Mexico.
No Californians have died from the swine flu, although two people have been hospitalized. One of them, a 35-year-old woman, was treated in intensive care before recovering.
Ten of California's 11 cases were reported in San Diego and Imperial counties, on the border with Mexico, and officials were puzzled by the lack of any clear link between them.
With the exception of a father-daughter pair in San Diego County, none of those infected appeared to have anything in common.
"They live distant distances from each other, they don't go to any of the same schools, churches, workplaces. They're really very independent cases from each other," said Dr. Gil Chavez, deputy director of the state's Center for Infectious Disease.
He said it was not known why the flu found in California was mild compared to that in Mexico. But he said he doubted that immunity played a role because the virus strain that appears to be involved in both countries is new in each.
Sorensen said the state was not considering quarantines because the incubation period is as short as too days.
"So by the time someone is sick, they've already shed virus before anyone even knew they were ill, and they can spread it so quickly," she said. "So it's really not logically realistic to use quarantine during influenza."
State health officials have not ordered any border restrictions but Gov. Arnold Schwarzenegger has advised Californians to take common-sense precautions.
(Additional reporting by Bernie Woodall and Steve Gorman in Los Angeles and Suzanne Hurt in Sacramento)