Here’s a great video showing how a flu virus invades your body and replicates itself.

It’s informative but interesting; the narrators are funny even while talking about a serious subject; and there are excellent animations to illustrate what a virus might look like and how it gets a foothold in the tissues of your nose and throat.

Notice also how the narrator uses everyday language to describe what is being shown, followed by the correct terminology: “knobby things on the virus surface” = “keys”.  When the term “key” is introduced, there appear images of door keys along the surface of the virus, which drives home the idea of how the virus locks into the cell surface of a human throat cell.  Then as the virus makes contact with the cell surface, there is the sound of a lock turning. This is a brilliant use of visual and audio effects to help viewers learn and remember the lock and key concept of viral invasion. Later, when the narrator describes how viruses copy themselves, there are sounds and flashing lights resembling a copying machine as the animation shows new virus particles being produced.

The double-teaming narration is also very effective, using a conversation between the NPR interviewer (Robert Krulwich) and the medical illustrator (David Bolinsky) to describe the entire process of viral invasion and immune system response.  I found this approach to be very appealing because the interviewer is asking questions that a viewer might ask while watching the video.  What are those pink things?  Why is the virus doing that? When the interviewer gets an answer, he interprets it in everyday terms.

Nicely done!