@article{oai:sapmed.repo.nii.ac.jp:00014547,
 author = {Oura, Asae and Ohnishi, Hirofumi and Hara, Megumi and Sakauchi, Fumio and Fushiki, Yasuhiro and Mori, Mitsuru},
 issue = {1-6},
 journal = {札幌医学雑誌 = The Sapporo medical journal, The Sapporo medical journal},
 month = {},
 note = {Background: Annual vaccinations are recommended for groups with high-risk medical conditions, as well as the residents of nursing homes. In general, little is known about the vaccine effectiveness of vaccines for Influenza-like illness （ILI） in community-dwelling elderly. Methods: A population based cohort study was conducted during the 2006-2007 （06/07） influenza season to examine the effectiveness of an influenza vaccine among community-dwelling elderly. We selected 1,000 elderly citizens ranging from 65 to 74 years old randomly from a population registry of Sapporo in September 2006. Baseline survey for them was conducted in October or November 2006, and 542 （54.2%） subjects responded with an informed consent. We excluded one person because he passed away before the follow-up survey. Thus, we analyzed 541 subjects. We followed-up the participants concerning acute febrile illnesses, hospitalizations, and so on every prior month from December 2006 to April 2007 though telephone interviews. The Chi-square test and Mann-Whitney U-test were used to compare vaccinated group to non-vaccinated group, and Cox’s hazard model was conducted to control for potential confounding factors. Results: After adjusting for confounders, the vaccination decreased acute fevers higher than or equal to 37.5°C （Hazard ratio （HR） =0.42, 95% confidence interval （CI）=（0.20, 0.90）） from December 2006 to March 2007, but was not associated with the risk of ILI （HR=1.25, 95%CI=（0.29, 5.37））. Conclusion: An influenza vaccination may decrease an acute fever during an influenza epidemic season in community-dwelling elderly.},
 pages = {31--37},
 title = {Effectiveness of Influenza vaccines in reducing risk of acute febrile illness among community-dwelling elderly, 2006-07 seasons : Population-based cohort study in Japan},
 volume = {78},
 year = {2009}
}