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WHO: Swine Flu Has "Pandemic Potential"

A deadly new swine flu strain that has killed at least 20 people in Mexico City and sickened more than 1,000 has "pandemic potential," the World Health Organization chief said Saturday - but some fear it may be too late to contain the outbreak.

With 24 new suspected cases of the swine flu reported Saturday, Mexico City said schools would remain closed and all public events suspended until further notice - including more than 500 concerts, sporting events and other gatherings including the popular weekly bicycle rides on streets closed to traffic.

A hotline set up the previous day fielded 2,366 calls from frightened city residents who suspected they might have the disease. City Health Secretary Armando Ahued said 10 new possible cases of infection have been discovered in the metropolis of 20 million people.

The Mexican government also issued a special decree clarifying Health Department powers to isolate patients and to inspect homes, incoming travelers and baggage to curb an outbreak of swine flu.

Officials say the decree gives clear legal authority to health department workers who might otherwise face lawsuits.

The decree published Saturday says President Felipe Calderon has authority to invoke the new powers when the situation warrants.

Officials say more than 1,000 people have been infected nationwide. Tests show 20 people have died of the swine flu, and 48 other deaths were probably due to the same strain.

Meanwhile, New York City health officials say at least eight schoolchildren have a type-A influenza virus. It could be swine flu, but officials won't know for sure until tests are conducted by the U.S Centers for Disease Control, reports CBS News correspondent Randall Pinkston.

The flu outbreak at St. Francis Prep in Queens is a troubling development. Of the eight strains of flu virus collected for testing, two came from students who had visited Mexico with their parents on spring break last week.

With at least 24 new swine flu cases in Mexico City confirmed today, American officials are keeping close watch on possible outbreaks north of the border, Pinkston reports.

The CDC confirms 10 cases of swine flu virus in the U.S. - two new cases in Kansas today, along with six yesterday in California and two in Texas.

"We do not think we can contain the spread of this virus," said Dr. Anne Schuchat, a top CDC official.

St Francis Prep is now sanitizing its building, as health officials worry about a possible swine flu pandemic.

"You could be looking at a significant number of people who are very ill and overwhelming our health care systems," said Dr. Myles Druckman, vice president of International SOS.

The illnesses in Texas and California have puzzled experts because none of the patients had contact with pigs, the typical avenue of transmission.

All of the American patients recovered, report CBS News correspondent Sandra Hughes, but she notes that more than 600,000 people cross the U.S.-Mexico border every day, creating a potentially wider outbreak.

This virus is a mix of human, pig and bird strains that has epidemiologists around the world deeply concerned. The World Health Organization convened in Geneva Saturday to consider whether to declare an international public health emergency - a step that could lead to travel advisories, trade restrictions and border closures.

The agency's director-general, Margaret Chan, said the outbreak involves "an animal strain of the H1N1 virus, and it has pandemic potential because it is infecting people.

"However, we cannot say, on the basis of currently available laboratory, epidemiological and clinical evidence, whether or not it will indeed cause a pandemic," she added.

(AP Photo/Alexandre Meneghini)
(Left: People wearing surgical masks as a precaution against infection at a subway station in Mexico City, April 24, 2009.)

It is the first time Chan has convened such a crisis panel since the procedure was created almost two years ago, a WHO spokesman said.

Speaking via a telephone news conference in Geneva, Chan said a new disease is by definition poorly understood, but that the situation involving this strain of swine flu is evolving quickly.

Meanwhile, the CDC and Canadian health officials were studying samples sent from Mexico, and some governments in Asia and Latin America began monitoring passengers arriving on flights from Mexico.

But it may be too late to contain the outbreak, given how widespread the known cases are. If the confirmed deaths are the first signs of a pandemic, then cases are probably incubating around the world by now, said Dr. Michael Osterholm, a pandemic flu expert at the University of Minnesota.

No vaccine specifically protects against swine flu, and it is unclear how much protection current human flu vaccines might offer.

On The Early Show, CBS News medical correspondent Dr. Jennifer Ashton said there is no cause for panic just yet. She said the concern being shown by health officials is because of how the flu has been transmitted.

"This is the first time that this particular strain has been seen in human beings, so it appears that the virus is starting to get smart and jump species; that's what they're tracking," Dr. Ashton said.

She said that people experiencing common symptoms of influenza - fever, body aches, headache, cough, runny nose, vomiting - who think they might have been exposed should see a doctor within the first 24 to 48 hours.

"This strain appears to be sensitive to the anti-flu medications," she said, but the prognosis is better the faster you are diagnosed and start treatment.

CDC Guidance For Clinicians

The Centers for Disease Control and Prevention recommend health professionals should consider the possibility of swine influenza virus infections in patients who show symptoms of febrile respiratory illness who:

  1. Live in San Diego County or Imperial County, California or San Antonio, Texas, or
  2. Have traveled to San Diego and/or Imperial County, California or San Antonio, Texas, or
  3. Have been in contact with ill persons from these areas in the 7 days prior to their illness onset.
If swine flu is suspected, clinicians should obtain a respiratory swab for swine influenza testing and contact their state or local health department to facilitate transport and timely diagnosis.

CDC Guidance For California And Texas Residents

CDC has identified human cases of swine influenza A (H1N1) virus infection in people in these areas. This virus is contagious and spreads from human to human; however, at this time we have not determined how easily the virus spreads between people. As with any infectious disease, we recommending precautionary measures for people in these areas.

  • Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
  • Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hands cleaners are also effective.
  • Try to avoid close contact with sick people.
  • If you get sick, CDC recommends that you stay home from work or school and limit contact with others to keep from infecting them.
  • Avoid touching your eyes, nose or mouth. Germs spread that way.
Because there is no vaccine available, it is important that people living in these areas take steps to prevent spreading the virus to others. If people are ill, they should attempt to stay at home and limit contact with others.

For more info:

  • Latest updates from World Health Organization
  • Information on Swine Flu from Centers For Disease Control and Prevention
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