(AP) -- In scores of schools across the United States, the mop has been the weapon of choice in the fight against swine flu. Schools from New York to California have spent days disinfecting desks and tables after cases of the virus turned up. But health experts say those cleanings probably do little to control the spread of the disease.

The main reason is that the flu usually can live for just a few hours once it leaves an infected person's body. That means even if a student sneezes on a desk, most traces of the virus will be gone overnight.

Health officials say the best way to stop transmission is to cover your mouth when you sneeze and wash your hands frequently.

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