Last week 7.3% of US deaths were caused by pneumonia and the flu, just above epidemic threshold, said the US Centers for Disease Control and Prevention.

BBC: New York State declares influenza emergency

Atlanta, Georgia (CNN) -- Nearly 3, 900 people, including about 540 children, are believed to have died from the H1N1 flu in the first six months of the epidemic, the Centers for Disease Control and Prevention said Thursday.

CNN: H1N1 death toll estimated at 3,900 in U.S.

Among a wide field of potent prescription painkillers -- which the Centers for Disease Control and Prevention says are fueling an epidemic of abuse in the United States -- hydrocodone may have been flying under the radar among doctors.

CNN: STORY HIGHLIGHTS