Safety of high doses of influenza vaccine and effect on antibody responses in elderly persons.

Keitel WA, Atmar RL, Cate TR, Petersen NJ, Greenberg SB, Ruben F, Couch RB. Safety of high doses of influenza vaccine and effect on antibody responses in elderly persons. Archives of internal medicine. 2006 May 22; 166(10):1121-7.

Dimensions for VA is a web-based tool available to VA staff that enables detailed searches of published research and research projects.

If you have VA-Intranet access, click here for more information vaww.hsrd.research.va.gov/dimensions/

VA staff not currently on the VA network can access Dimensions by registering for an account using their VA email address.    Search Dimensions for VA for this citation
* Don't have VA-internal network access or a VA email address? Try searching the free-to-the-public version of Dimensions

Search for Abstract from PubMed

---

Abstract:

BACKGROUND: Immune responses after influenza immunization are reduced in elderly individuals, the group at greatest risk for complications and death after influenza. Improved vaccines are needed to address this problem. METHODS: Ambulatory individuals 65 years and older (N = 202) were assigned randomly to receive a single intramuscular injection of the 2001-2002 formulation of trivalent inactivated influenza vaccine containing 15, 30, or 60 microg of hemagglutinin per strain (up to 180 microg total per dose) or placebo. Clinical and serologic responses were assessed during the month after immunization. RESULTS: Increasing dosages of vaccine elicited significantly higher serum antibody levels, frequencies of antibody responses, and putative protective titers after vaccination. Mean serum hemagglutination inhibition antibody titers 1 month after immunization in groups given 0-, 15-, 30-, and 60-microg dosages were 23, 37, 50, and 61 against influenza A/H1N1; 43, 86, 91, and 125 against influenza A/H3N2; and 10, 14, 18, and 24 against influenza B, respectively. Mean serum hemagglutination inhibition and neutralizing antibody levels against the 3 vaccine antigens in participants given the 60-microg dosage were 44% to 71% and 54% to 79%, respectively, higher than those in participants given the standard 15-microg dosage, and the 60-microg dosage level nearly doubled the frequency of antibody responses in those whose preimmunization antibody titers were in the lower half of the antibody range. Dose-related increases in the occurrence of injection site reactions were observed (P < .001), but all dosages were well tolerated. CONCLUSION: The improved immunogenicity of high-dose influenza vaccine among elderly persons should lead to enhanced protection against naturally occurring influenza.