• If you’ve been debating whether to get a flu shot, you should watch this beautifully terrifying 3 minute animation by NPR of a virus taking over a cell and sending millions of its progeny off to spread the infection.

A single virus particle can turn an infected cell into a factory capable of producing millions more virus particles, which it sends out to infect other cells. To fight that onslaught, your immune system has to be able to destroy virus particles before they can spread and infect healthy cells. The good news is that usually, your immune system is on top of things.