Factors associated with maintenance of antibody responses to influenza vaccine in older, community-dwelling adults
Published Date:Apr 23 2015
Source:BMC Infect Dis. 15.
Pubmed Central ID:PMC4415221
Funding:1U18 IP000184-01/IP/NCIRD CDC HHS/United States
5 U18 IP000183-02/IP/NCIRD CDC HHS/United States
K23 AI074863-01A1/AI/NIAID NIH HHS/United States
UL1TR000445/TR/NCATS NIH HHS/United States
Little is known about factors associated with maintenance of hemagglutinin inhibition (HAI) antibodies after influenza vaccination in older adults.
Adults ≥50 years of age were vaccinated prior to the 2009–10 influenza season. Serum was drawn pre-vaccination (S1), 21–28 days post-vaccination (S2), and after the influenza season (S3) for HAI assays. Seroconversion was defined as ≥ 4-fold increase S1 to S2 (or if S1 < 10, by an S2 ≥ 40) and seroprotection was defined as S2 ≥ 40. Maintenance of antibody response was measured in participants with an S2 ≥ 40, and defined as an S3 ≥ 40.
We enrolled 510 participants during Fall 2009 at Vanderbilt University Medical Center and Marshfield Clinic Research Foundation. Participants’ mean age was 64 years with 62% female and 96% white. Seroconversion and seroprotection rates were lowest for influenza A H1N1 (12% and 26%, respectively), highest for influenza A H3N2 (45% and 82%), and intermediate for influenza B (28% and 72%). Of the participants with an S2 ≥ 40, 36% (46/126), 71% (289/407), and 74% (263/354) maintained an S3 ≥ 40 for H1N1, H3N2, and B influenza vaccine strains, respectively. S1 HAI titer was strongly associated with both post-vaccination seroprotection and maintaining seroprotection at S3 for all three influenza antigens. Age, sex, body mass index, self-reported stress, and vaccination site were not consistently associated with vaccine response or maintenance of response.
Pre-vaccination antibody titer was the only study variable consistently and positively associated with both serologic response to vaccination and maintenance of response. Antibody responses were lowest for the H1N1 vaccine strain.
gov Identifier: NCT02401893
Electronic supplementary material
The online version of this article (doi:10.1186/s12879-015-0926-8) contains supplementary material, which is available to authorized users.
image/gif image/jpeg image/gif image/jpeg text/plain text/plain
You May Also Like: