The CDC’s Morbidity and Mortality Weekly Report notes that the overall effectiveness of this year’s seasonal flu vaccine was 56%. But the seasonal vaccine failed to protect seniors 65 years and older. Among older people, the vaccine was only 9% effective against the harshest type of flu (the more virulent H3N2 strain). Overall, the report stated, influenza vaccination reduced the risk for medical visits for influenza by about approximately one half to two thirds for most people, except for older adults. “The vaccine effectiveness was lower and not statistically significant among older adults,” the CDC report stated.
A new government report on the effectiveness of this year’s flu vaccine finds dramatic discrepancies in the amount of protection Americans received, with senior citizens being left the most vulnerable….
The new report from the Centers for Disease Control and Prevention found the vaccine offered 58 percent protection against the most common and dangerous H3N2 strain for children ages 6 months to 17 years old, 46 percent protection for adults ages 18 to 49, and 50 percent protection for adults 60 to 64 years of age….
For adults 65 and older, the vaccine was found to be 27 percent effective against the three strains, according to the new report — the lowest in about a decade, but not far below from what’s expected. But the vaccine did a particularly poor job of protecting older people against the harshest flu strain, and CDC officials say it’s not clear why….
Schaffner serves on the CDC’s Advisory Committee on Immunization Practices, which selects the strains included in the vaccine each year. At a committee meeting today where the new data was presented, Schaffner described the mood as unhappy, with experts “scratching their heads” as to why the vaccine’s effectiveness was “unexpectedly low” against the virulent H3N2 strain for this age group….”That’s a nasty combination,” he said at the time. The new report’s findings that the vaccine wasn’t very effective against H3N2 likely contributed to seniors being hit hardest this flu season, he said Thursday….
The CDC told Dr. LaPook that better vaccines are needed and that this is the subject of very active research, adding it was “disappointed” by the low effectiveness rate against this year’s most common flu strain. But, there is definite benefit to the vaccine “and it continues to be the most important weapon,” according to the agency.