The French microbiologist Louis Pasteur never heard of the coronavirus, but he knew a thing or two about infectious diseases. One of the things he knew was that there are two primary components in any infectious disease: the pathogen and the host. The pathogen (i.e., a virus) is what infects, while the host (you) is what is infected.

Pasteur, who spent his life studying pathogens, was famously quoted as saying: “The bacteria are nothing. The soil is everything.” I shorthanded this statement to “Look to the host” in grad school and have been referencing it ever since.

This is good advice for these times, and here’s why

Pasteur realized that all the info in the world about the nature of germs and microbes wouldn’t do much good without a greater understanding of how they interact with the host. Because, ultimately, with any virus that comes to mind, more people are infected than ultimately succumb. The question is why. Why do some people who’ve been exposed to a microbe get sick while others, exposed to the exact same microbe, don’t?