This is of course easy to check in the dictionary:

https://www.merriam-webster.com/dictionary/virulence

https://www.merriam-webster.com/dictionary/pathogenicity

But I feel it is easier to explain these two together, and of course with an illustration 🙂

If you want to read a bit more about pathogenicity and virulence, check out Wikipedia. I can just hear my professors moan when I refer to Wikipedia, but it was nicely written and I really liked this one. And remember, if you need a source and you are not allowed to use Wikipedia, check out the sources Wikipedia uses =)

(https://en.wikipedia.org/wiki/Pathogen last accessed 21.05.2021)