NORWALK - Local health officials are on high alert after the U.S. government declared a public health emergency due to the swine flu.

At Stamford Hospital, Dr. Michael Parry says the virus moves very quickly. He fears Connecticut could see cases of swine flu over the next few days.

More than 1,600 people have become sick with the virus so far. In the United States, 20 cases have been confirmed, eight of which are in New York. Mexico remains the hardest hit area with 103 deaths.

In Mexico City, extra precautions are being taken to prevent further spreading of the virus. Subway passengers are wearing surgical masks and public events have been canceled.

Federal health officials say swine flu contains strains of the human virus, the avian flu virus and pig viruses from Europe and Asia. Symptoms of the virus include fever, lethargy, loss of appetite and coughing.

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