Pathogens are microorganisms which can cause disease. These include bacteria, viruses and fungi. Have a look at the little things!

(Did you know viruses aren’t actually “alive”? They’re more like seeds – they multiply under certain conditions, but otherwise, they’re dead.)

Pathogens can cause disease when they invade the interface between an organism and their environment. This could be someone’s skin, lungs, digestive system, etc.

There are two ways which you need to know about in which pathogens cause disease: 1) damage to the cells, and…