If you decide to implement the Future CSI unit, there are some great online resources that you may want to consider. As recommended in the unit, have students read the virus information on the How Stuff Works web site. This information is good for middle/high school students, but is too advanced for younger students.
Another resource that is really helpful are the video clips that are available through UnitedStreaming (anyone can get a free trial account for 3o days). The two videos I found useful were The Influenza Pandemic of 1918 and Introduction to Viruses.