The San Francisco Health Department confirmed Thursday that one San Francisco child has the swine flu. The child is not in school and recently traveled to Mexico.
San Mateo County Health Director Dr. Scott Morrow said there are two "probable" cases of the swine flu in his county.
He said a 46-year-old woman with extremely mild symptoms and had not traveled to Mexico and a 50-year-old person who lives in another state but is visiting has mild illness.
Both people have recovered.
The Santa Clara County Public Health Department also announced that there are four probable cases of swine flu in the county.
The first case, reported Tuesday, was a 16-year-old female student of Branham High School in San Jose, according to health officials. School officials will keep the school closed until May 6 to help prevent the virus from spreading.
The health department reported three new probable cases of swine flu affecting a 30-year-old man who did not require hospital treatment and is recovering; a 32-year-old woman who had recently traveled to Mexico and who also has not required hospital treatment; and a 53-year-old woman.
In addition to the four probable cases in Santa Clara County, at least three probable cases have been reported in Contra Costa County, where schools have also been affected, and at least two probable cases have been reported in Marin County.
As of this morning, the Centers for Disease Control and Prevention confirmed 91 cases of swine flu in the U.S., including one fatal case in Texas. There were 14 confirmed cases in California.
Gov. Arnold Schwarzenegger declared a state of emergency in response to the virus Tuesday morning, which allows the California Emergency Management Agency to work with the state Department of Public Health to prevent the disease from spreading, governor's spokesman Jeff Macedo said.
After the World Health Organization announced it has raised the pandemic alert from phase 4 to phase 5, Schwarzenegger issued a statement reading, "From the moment the first cases of swine flu arose in California, my administration has responded vigorously by deploying resources and preparing for the additional cases of swine flu we are now seeing. We are already taking the steps that are appropriate for a level 5 pandemic alert."
Health officials are urging people not to panic. The H1N1 virus is a new virus that people don't have a natural immunity to, but most people in the U.S. who have come down with the illness reported mild symptoms, according to health officials.
The swine flu outbreak was first reported in the U.S. in late March in Southern California and Texas, according to health officials. It is spread mainly person-to-person through coughing and sneezing.
An estimated 30,000 people in the U.S. die each year from the seasonal flu.
Health officials in Contra Costa County are testing a "cluster" of children who attend Marina Vista Elementary School in Pittsburg for swine flu today after eight students reported feeling ill, according to Contra Costa Director of Public Health Dr. Wendel Brunner.
Highland Elementary School, which is also in Pittsburg, and Branham High School in San Jose were closed today after four students were identified as probable cases. Both schools will remain closed until May 6.
A public school in San Bernardino is also closed as well as a private school in Sacramento, State Superintendent of Public Instruction Jack O'Connell said at a news conference in Pleasant Hill this afternoon.
There are 14 confirmed cases of swine flu in California and a total of 91 confirmed cases nationwide. One person in Texas has died from the virus, according to the Centers for Disease Control and Prevention.
Health officials are urging parents not to send their children to school if they are sick.
"We're asking people if they're sick to stay home," Brunner said.
People should also take precautions, such as washing their hands with soap and hot water and covering their mouths with their arms when they cough, to prevent the spread of the disease. People should stay home for at least 24 hours after they stop experiencing symptoms to avoid infecting others.
Health officials are also urging people not to panic. While the H1N1 virus is a new virus that people don't have a natural immunity to, most people in the United States who have come down with the illness reported mild symptoms, according to Brunner.
The illness also responds well to anti-viral drugs that the Centers for Disease Control and Prevention has been stockpiling.
"If your child is healthy, he or she should go to school," Contra Costa County Superintendent Joseph Ovick said.
Schools are required to have safety plans that include response to a pandemic flu.