A Laboratory Evaluation of the Humoral Immune Response in Adults and Children to the H1 Hemagglutinin (HA) Stalk Domain and Other Influenza A Virus Protein Epitopes, After Administration of GlaxoSmithKline (GSK) Biologicals' Pandemic Influenza Vaccines

Inclusion Criteria:

Not applicable since no subjects will be actively enrolled in this study; only the sera
samples of the subjects who were a part of previously conducted primary trials will be used
for testing. However, the archived serum samples of only those subjects who satisfy the
following criteria will be included in this study:

- Subjects who received two doses of influenza vaccine 21 days apart and were included
in the ATP cohort for immunogenicity and Persistence cohort (depending on the study)
in the primary studies listed.

- Subjects who had agreed that their blood samples could be used for further research
while giving informed consent for any of the primary studies listed.

- Subjects who have sufficient residual sample volume (i.e., ≥0.5 mL) of serum at all
time points.

- Subjects with vaccine homologous neutralizing antibody result available at Day 0 and
at 21 (25 samples available per group in Study H9N2-001)

Exclusion Criteria:

- Not applicable since no subjects will be actively enrolled in this study; only the
serum samples of the subjects who were a part of previously conducted trials will be
used for testing.