Could a vitamin d boost make flu shots work better for seniors?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: \- Aged 65 or over subject, * Subjects with a vitamin D levels below 30 ng / ml, * Acceptance of vitamin D (100 000 IU of UVEDOSE ®) * Acceptance of influenza vaccination with INTANZA15 ® * Affiliation to a social security scheme * The subject agrees not to change their eating habits Exclusion Criteria: * Liver disease: cirrhosis, chronic hepatitis. * Renal impairment whatever degree * Hypercalcemia (serum calcium\> 2.6 mol / l) * Hypo-or hyperparathyroidism history, history of renal colic. * Disease / acute infection, moderate or severe (at the discretion of the investigator) on the day of vaccination or febrile illness (temperature ≥ 38 ° C). The subject should not be included in the study as his condition is not cured or her fever has not gone down). * Long-term treatment with bisphosphonates, corticosteroids, anti-inflammatory, anticonvulsant, antiepileptics, fibrates. * Known hypersensitivity to vitamin D * Prior supplementation (in the last year) or supplementation of vitamin D during * Participation at the time of inclusion in the trial, or planned participation during the same period that this trial, another trial on a vaccine, drug, medical device. * Vaccination during the 4 weeks prior to vaccination or immunization of the test set out in the three weeks after vaccination test. * Transfusion of immunoglobulins, blood or blood products during the last 3 months * Congenital or acquired, known or suspected immunodeficiency, immunosuppressive therapy in the last 6 months, such as cancer chemotherapy or radiotherapy; steroids long-term systemic (prednisone or equivalent for more than two consecutive weeks in the Previous 3 months). * Systemic Hypersensitivity to any component of the vaccine (ovalbumin, chicken protein, neomycin, formaldehyde, octoxinol 9), or a history of reaction to influenza vaccine or a vaccine containing one of the substances in the vaccine trial, which involved life-threatening. * Deprivation of liberty or by administrative order issued by a court, subject to emergency medical or involuntary hospitalization. * Topic enjoying a measure of legal protection (guardianship, guardianship ...).