- Administration of any vaccine (including any other influenza vaccine) within a 30 day period prior to study enrolment, or planned administration within the period from the first vaccination up to blood sampling at Day 42 or within 30 days prior to blood sampling at Day 228. Immunization on an emergency basis of a tetanus and diphtheria toxoids adsorbed for adult use (Td) will be allowed provided the vaccine is not administered within two weeks prior to test article administration. Receipt of any other emergency immunizations (e.g. rabies) will result in a case-by-case review of continued participation.