Five short months ago, fear of the swine flu gripped the state and the nation. Health officials warned that the flu season could be one of the deadliest in decades. The anxiety intensified when President Barack Obama declared a state of emergency.

The H1N1 swine flu virus can develop resistance quickly to antivirals used to treat it, U.S. doctors reported.

U.S. doctors reported on Friday that the H1N1 swine flu virus can develop resistance to antivirus treatments very quickly.Government researchers reported cases of two persons with compromised immune systems who developed new strains of the virus after less than two weeks of therapy.

Reuters. WASHINGTON. The H1N1 swine flu virus may have been new to humanity in many ways but in one key feature its closest relative was the 1918 pandemic virus, researchers reported on Wednesday.

Tennessee health officials say there may continue to be local outbreaks of swine flu for weeks or months.