Twice as many doses have gone to children than adults, but only about 2 million children had received the second dose of the swine flu vaccine, according to a CDC telephone survey ending Dec. 12.
"There are a lot of children in need of second doses in the weeks ahead," Anne Schuchat, MD, director of the National Center of Immunization and Respiratory Diseases, said at the briefing.
Schuchat dismissed a recent Australian study that suggested that a single dose of vaccine could be enough for children under 10. "We strongly believe that two doses are needed in children."
The CDC recommends that children under age 10 get the two doses at least four weeks apart -- though a longer gap of five to six weeks is fine.
Half of Americans Want H1N1 Vaccine
The CDC's telephone survey indicates that about half of Americans have gotten or would like to get the H1N1 vaccine. And with 111 million doses now available, it should be widely available in doctors' offices, public health departments, drug stores, and even shopping malls.
Swine flu cases have fallen off, with only 11 states reporting widespread disease activity. Schuchat urged Americans not to become complacent and skip the vaccine -- particularly those with chronic health conditions who often do not realize that they fall in a group at high risk for developing complications from influenza. "The time is now for adults with chronic health conditions to look for vaccines ... people with lung disease like emphysema, diabetes, cancer, and heart disease," Schuchat said.
The CDC also confirmed that it has received reports of H1N1 swine flu in some household pets, saying that the "human-animal interface" is an important scientific aspect of this influenza virus. But it's so rare, the CDC says there's no reason for owners of cats and dogs to be concerned.