A Study of Swine-origin A/H1N1 Influenza Vaccines in Healthy Europeans Children Aged 6 to 35 Months

Inclusion Criteria : All subjects * Aged 6 to 35 months on the day of inclusion * Informed consent form has been signed and dated by the parent(s) or other legally acceptable representative * Subject and parent/legal representative are able to attend all scheduled visits and to comply with all trial procedures * Completion of vaccination according to the national immunization schedule. Subjects ≥ 6 to \< 24 months of age - Born at full term of pregnancy (≥ 37 weeks) and with a birth weight ≥ 2.5 kg At Month 8 for antibody persistence assessment: * Having received two half-doses of either the formulation 1 or 2 of the vaccine * Addendum 1 to Informed Consent Form has been signed and dated by the parents or other legally acceptable representative. At Visit 06, for subjects eligible for the Antibody persistence evaluation who will receive the Trivalent Influenza Vaccine (TIV): \- Addendum 2 to Informed Consent Form has been signed by the subject's parents/legal representative. Exclusion Criteria : All subjects * Participation in another clinical trial investigating a vaccine, drug, medical device, or a medical procedure in the 4 weeks preceding the first trial vaccination * Planned participation in another clinical trial during the present trial period * Receipt of any vaccine in the 4 weeks preceding the first trial vaccination * Planned receipt of any vaccine prior to the Day 42 blood sample * Receipt of blood or blood-derived products in the past 3 months which migh…