Authorities earlier had said the flu vaccine was 62 percent
effective for adults and children. In the Thursday report, the
CDC revised that to 56 percent. The new number, the agency said,
is "not significantly different" and continues to fall within
the confidence interval established earlier. But the lower
number includes an additional three weeks of data and was
adjusted for various factors, including age and race or
ethnicity. "Both estimates indicate moderate vaccine
effectiveness in preventing outpatient medical visits due to
circulating flu viruses in most of the population," the report
said. In addition, while this year's vaccine was considered a
good match for the most common circulating flu viruses, it only
provided 47 percent protection against H3N2, the main virus. "We
simply need a better vaccine against influenza, one that works
better and lasts longer," Frieden said. The Department of Health
and Human Services as well as the private sector are working on
such a project, he said. In addition, les