The purpose of this study is to evaluate how effective the vaccine is at preventing subjects developing flu symptoms after they are directly exposed to flu virus. The study will also evaluate how well the vaccine is tolerated at sites where administrations are given, any effects it may have on subjects' wellbeing and whether it can produce antibody responses in the body

Influenza is a contagious disease of the upper airways and the lungs. It rapidly spreads around the world in seasonal epidemics, killing hundreds of thousands of people and having high economic consequences due to healthcare costs and lost productivity. Each year governments recommend groups who are at risk of influenza or its complications to receive influenza vaccination. Current vaccine supply is not sufficient to meet the demand if this recommendation were to be taken up by all. This study will evaluate PowderMed's Particle Mediated Epidermal Delivery (PMED) DNA vaccine for influenza as a potential alternative to existing vaccine technologies. This study will assess how effective two different PMED vaccine combinations are at preventing subjects developing influenza following exposure to flu virus 56 days after a single dose of vaccine.

Inclusion Criteria:

Healthy adult volunteers (women must be of non child-bearing potential)

Provided written informed consent

Exclusion Criteria:

No significant concomitant illness

No allergy to gold

No immunosuppression due to disease or treatment

Pre-existing protective level of antibody against the challenge virus strain