Mayor Michael Bloomberg says the Centers for Disease Control has confirmed eight cases of swine flu at a Queens high school after dozens of students reported mild flu-like symptoms this past week.

The mayor made the remarks during a press conference in East Harlem Sunday afternoon and is asking the public to remain calm despite recent cases of the flu strain around the U.S.

The CDC confirmed eight cases in students at Saint Francis Prep in Fresh Meadows after samples were sent to a lab for further study.

As a precaution, the school will remain closed Monday and Tuesday.

School workers spent the day Sunday scrubbing down every surface of the school, trying to rid it of the flu bug.

Mayor Bloomberg says the city is closely monitoring the outbreak and assured New Yorkers that all of the reported cases have been mild, but that precautions should still be taken.

"To members of the public: if you have fever and cough or sore throat, stay home. Do not go to work or to school. Wash your hands frequently and as always, when you cough or sneeze, cover your mouth and nose. This is how to reduce the risk of transmitting this illness," said Bloomberg.

Despite the mayor's calm reassurance, all St. Francis Prep parent Kathy Pinzel could feel was panic Her daughter, a senior at St. Francis, has had flu-like symptoms since Thursday. She doesn't feel like she's got straight answers from school and city leaders about how bad the outbreak was.

"It's very scary and they make it out like it's a mild case," Pinzel said. "Well it may be mild, but it's a lot of children and by not telling parents, your only scaring us more."

Health officials say the cases of swine flu in Mexico City have been more severe and may have even led to several deaths. They say patients in the U.S. have recovered without treatment from hospitals.

Senator Charles Schumer also attended the press conference and says the CDC is working with City Health Commissioner Tom Frieden to monitor the situation.

"They have the most advanced testing that there is, and will be readily available on an hour-by-hour basis to the city. Second, monitoring Mexico and third, providing support. There are people from CDC here working with Tom's folks in New York," said Schumer.

The city's health department was also looking into a possible outbreak at a Bronx day care facility, where 30 children got sick. Five of the six samples sent out for testing, however, came back negative.

Department officials say they haven't seen any recent city-wide increases in flu-like symptoms, but that they are monitoring the situation every 12 hours to make sure more people aren't getting sick.

Health Commissioner Tom Frieden is urging anyone who feels sick to stay home, but says the city is ready for any emergency.

"The city is very well prepared. We have been preparing for years at every level. We've been preparing with detection, so we can track whether a pandemic or other serious problem comes, and if so where it is, what the characteristics are," said Frieden.

Governor David Paterson has also directed the state Department of Health to monitor and respond to possible cases of swine flu. He says 1,500 treatment courses of the antiviral Tamiflu have been sent to New York City.

Overall, federal health officials have confirmed at least 20 cases of swine flu across the country. They're now declaring a public health emergency as a precautionary measure, to give state and federal governments easier access to flu tests and medications.

The Centers for Disease Control says cases have been reported in Ohio, Kansas, Texas, California and New York.

Health officials say all of the cases that have been reported involve mild symptoms, but are expecting more cases and more severe illness to pop up among Americans.

"As we continue to look for cases we are going to continue to see a broader spectrum of disease. What we know about this virus is it looks to be the same virus as is causing the situation in Mexico. And given the reports out of Mexico I would expect over time we're going to see more severe disease in this country,” said CDC Acting Director Richard Besser.

Homeland Security Secretary Janet Napolitano says roughly 12 million doses of the drugs Tamiflu and Relenza are being released from a federal stockpile so that states can get it if needed. Both are anti-viral drugs, believed to be effective in treating severe cases of the flu if taken early enough.

Meanwhile, New Zealand's health minister says 10 students who just returned from Mexico have tested positive for influenza and that the cases are "likely" to be swine flu.

The news comes a day after two dozen new suspected cases of flu were reported in Mexico City.

The World Health Organization says at least 81 people have died from severe pneumonia caused by a flu-like illness in Mexico. Tests have confirmed swine flu as the cause of death in 20 of the cases.

In response to the outbreak, Mexican President Felipe Calderon has assumed new powers to isolate infected people.

The powers also allow the country's health department to inspect homes, incoming travelers and luggage.

The U.S. Embassy is warning Americans traveling in Mexico to avoid crowds.

The White House says President Barack Obama's health is fine a little more than a week after he visited Mexico, and that he is being updated regularly on the flu outbreak.