Enhanced Flu Vaccines Elicit Greater Antibody Responses in Older Adults

A meta-analysis published in the Journal of Infectious Diseases found enhanced influenza vaccines trigger greater antibody responses compared with standard-dose vaccine in older adults, reports Healio . The investigators analyzed PubMed, Medline, and Embase for studies published through Dec. 31, 2017, of enhancements in antibody responses as quantified by hemagglutination inhibition (HAI) assay linked to enhanced vaccines versus standard-dose vaccine. Thirty-nine randomized controlled trials were highlighted. The trials indicated men and women 60 or older who received enhanced vaccines underwent higher post-vaccination titers for all vaccine strains, and higher proportions with elevated titers of 40 or greater for most strains in comparison to adults of the same age getting standard-dose vaccines. The "most notable" difference was observed with influenza A(H3N2), with high-dose vaccine producing an 82 percent higher post-vaccination titer to the strain versus standard-dose vaccine. "This was significantly higher than 52 percent estimated for MF59-adjuvantated vs. standard dose vaccines (P = .04), which was higher than 32 percent estimated for intradermal vs. standard-dose vaccines (P