Sensitivity analyses exploring the impact of changing selected parameter values on the model results.^*

*See table 1 for base case parameter values. **National data suggest that adults >25 years of age tend to have higher vaccination rates than persons 18 to 25 years of age.[see Centers for Disease Control and Prevention, Behavioral Risk Factor Surveillance System data for influenza vaccination for 2005: http://www.cdc.gov/brfss]. ***These scenarios were constructed to explore the impact of withdrawal of symptomatic persons with resulting decreases in infectious contact rates on TARs.