This season’s flu vaccine was less effective overall than in other years, and failed to protect most seniors from one acute strain of virus, according to this week’s CDC Morbidity and Mortality Weekly Report.
The late-February adjusted estimates rate the vaccine at 56 percent effective overall—somewhat less than the usual 50–70 percent.
Of the three strains of virus included in the vaccine—influenza A (H3N2), influenza A (H1N1) and influenza B—the influenza B component was relatively effective across all age groups, with an efficacy rating of 67 percent. But the influenza A (H3N2) component saw a severe drop off in efficacy for those age 65 or older, protecting only 9 percent of those vaccinated in that age group.
The report has immediate impact on skilled nursing and senior living communities, whose primary residents are within the critical age group and often have high-acuity conditions. In response to the data, the CDC issued clinical care suggestions for treating those over 65:
“This season, antiviral treatment of elderly adults is especially important,” the CDC report suggests. “CDC recommends initiating antiviral medications for patients with suspected influenza, regardless of their influenza vaccination status, if they are aged ≥65 years, or hospitalized, or have progressive or complicated illness, or otherwise are at higher risk for complications from influenza. Antiviral treatment can be initiated empirically, preferably within 48 hours after illness onset, and should not be delayed pending confirmatory diagnostic testing nor be dependent upon tests with limited sensitivity (e.g., negative rapid tests).”
The flu vaccine is a preventive measure, not a silver bullet. However, the disappointing numbers during an especially aggressive flu season have some experts pushing for research on an improved type of vaccine. “We simply need a better vaccine against influenza, one that works better and lasts longer,” CDC Director Thomas Frieden said in a Reuters article.
At least three pharmaceutical companies have received Food and Drug Administration approval for new types of flu shots in the past three months, including Novartis, GlaxoSmithKline and Protein Sciences Corp., Reuters reported.