Dataset Information

Immuno-epidemiologic correlates of pandemic H1N1 surveillance observations: higher antibody and lower cell-mediated immune responses with advanced age.

ABSTRACT:

Background

Pandemic H1N1 (pH1N1) surveillance data showed lower attack rates but higher risk of severe outcomes with advanced age. We explored immuno-epidemiologic correlates of surveillance findings including humoral and cell-mediated immunity (CMI).

Methods

In an age-based design, ?100 banked/residual sera per 10-year age stratum were assessed by hemagglutination inhibition (HI) and microneutralization (MN) assays for preexisting antibody to pH1N1 and recent seasonal H1N1 and H3N2 strains. In a separate birth cohort design defined by childhood influenza A/subtype priming (1919-1929: H1N1; 1945-1949: H1N1; 1958-1960: H2N2; 1969-1970: H3N2; 1978-1989: H3N2/H1N1), whole blood was collected from up to 50 volunteers per birth cohort. The ratio of Th1(IFN-?):Th2(IL-10) cytokine responses was evaluated in vitro.

Results

Antibody to seasonal viruses was highest in school-age children. Cross-reactive HI/MN antibody to pH1N1 was low among participants <70 years of age (yoa; 6%/4% ? 40), but seroprevalence increased at 70-79 yoa (27%/6%), increased even more at 80-89 yoa (65%/47%), and was highest at ?90 yoa (88%/76%). CMI to pH1N1 was evident in all 5 birth cohorts but was lower compared with seasonal strains. There was little differentiation by subtype priming, but the Th1:Th2 ratio for all viruses dropped significantly in the 2 oldest cohorts.

Conclusions

Preexisting antibody may have protected the very old from pH1N1 infection, while diminished CMI may have contributed to greater severity once infected. In the young, cross-reactive pH1N1 antibody was mostly absent, while more intact CMI may have protected against severe outcomes.

SUBMITTER: Skowronski DM

PROVIDER: S-EPMC3071066 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Publications

Immuno-epidemiologic correlates of pandemic H1N1 surveillance observations: higher antibody and lower cell-mediated immune responses with advanced age.

Skowronski Danuta M DM Hottes Travis S TS McElhaney Janet E JE Janjua Naveed Z NZ Sabaiduc Suzana S Chan Tracy T Gentleman Beth B Purych Dale D Gardy Jennifer J Patrick David M DM Brunham Robert C RC De Serres Gaston G Petric Martin M

The Journal of infectious diseases 20110101 2

<h4>Background</h4>Pandemic H1N1 (pH1N1) surveillance data showed lower attack rates but higher risk of severe outcomes with advanced age. We explored immuno-epidemiologic correlates of surveillance findings including humoral and cell-mediated immunity (CMI).<h4>Methods</h4>In an age-based design, ∼100 banked/residual sera per 10-year age stratum were assessed by hemagglutination inhibition (HI) and microneutralization (MN) assays for preexisting antibody to pH1N1 and recent seasonal H1N1 and H3 ...[more]

PMID: 21288814

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Dataset Information

Immuno-epidemiologic correlates of pandemic H1N1 surveillance observations: higher antibody and lower cell-mediated immune responses with advanced age.

Background

Methods

Results

Conclusions

Publications

Immuno-epidemiologic correlates of pandemic H1N1 surveillance observations: higher antibody and lower cell-mediated immune responses with advanced age.

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