Swine flu struck hundreds people in Mexico City, California and Texas, raising the threat of pandemic and leading health authorities to distribute masks and shutter schools, museums, movie theaters and libraries.
At least 81 died and more than 1,000 became sick with flu.
U.S. authorities said seven people were infected with swine flu in California and Texas, and all recovered.
Health officials urged anyone with a fever, a cough, a sore throat, shortness of breath or muscle and joint pain to seek medical attention.
It can be cured if detected on time.
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