title: Influenza vaccination among college and university students: impact on influenzalike illness, health care use, and impaired school performance.
abstract: OBJECTIVE
  To assess influenza vaccine effectiveness against influenzalike illness (ILI) and ILI impact on health care use and school performance among college and university students.
  
  
  METHODS
  Pooled analysis of 4 consecutive cohorts for the 2002-2003 through 2005-2006 seasons.
  
  
  METHODS
  Twin Cities campus of the University of Minnesota (2002-2003 through 2005-2006 seasons) and St. Olaf College in Northfield, Minnesota (2005-2006 season).
  
  
  METHODS
  Full-time students received e-mail invitations to participate in single-season cohorts. Internet-based surveys collected baseline (October) and follow-up (November-April) data.
  
  
  METHODS
  Influenza vaccination.
  
  
  METHODS
  Proportion of students with ILI. Multivariable regression models assessed the effectiveness of vaccination for reducing ILI during months when influenza was circulating while controlling for confounders and after pooling data across the 4 cohorts.
  
  
  RESULTS
  There were 2804, 2783, 3534, and 3674 participants in the 2002-2003, 2003-2004, 2004-2005, and 2005-2006 cohorts respectively, and overall, 30.2% were vaccinated. In the pooled analysis, 24.1% of students experienced at least 1 ILI during influenza seasons. Vaccination was associated with a significant reduction in the likelihood of ILI during influenza seasons (adjusted odds ratio, 0.70; 95% confidence interval, 0.56-0.89) but not during noninfluenza periods (adjusted odds ratio, 0.98; 95% confidence interval, 0.73-1.30). Vaccination was also associated with significant reductions in ILI-associated provider visits, antibiotic use, impaired school performance, and numbers of days of missed class, missed work, and illness during the influenza seasons.
  
  
  CONCLUSIONS
  Influenza vaccination was associated with substantial reductions in ILI and ILI-associated health care use and impairment of school performance. College and university students can experience substantial benefits from influenza vaccinations.
authors.affiliation: VA Medical Center, Minneapolis, MN 55417, USA. nicho014@umn.edu
authors.forename: Kristin L
authors.initials: KL
authors.lastname: Nichol
authors.forename: Sarah
authors.initials: S
authors.lastname: D'Heilly
authors.forename: Edward P
authors.initials: EP
authors.lastname: Ehlinger
mesh_terms: D000328:Adult; D003695:Delivery of Health Care / Q000706:statistics & numerical data*; D004521:Educational Measurement / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control*; D008297:Male; D009017:Morbidity / Q000639:trends; D012189:Retrospective Studies; D013334:Students / Q000523:psychology* / Q000706:statistics & numerical data; D013997:Time Factors; D014495:Universities / Q000706:statistics & numerical data*; D014611:Vaccination / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines