@Hannah259 Boy, can I related to your post. I had a very similar bloody fiasco my first few weeks as a host; along with my newly painted and decorated Beach Cottage being left in a state of disarray. Clean up required lots of bleach and lots of intensive scrubbing to ensure the walls, shower, counters, etc where blood was spattered everywhere (via the lungs of the guest) were properly sterilized - AND, my next guests were coming only four hours later. It was one of the most stressful things I had ever been through in my life, and that is saying something. I could only be grateful that my co-host was willing to help clean up, and that he had already bought bleach, plastic gloves and face masks, which we needed to safely deal with the bodily fluids that may or may not have been 'contaminated' (having worked in hospital settings, I take the hazardous nature of dealing with the bodily fluids of strangers very seriously).
In my case, I called Airbnb BEFORE contacting these guests, and I was NOT told to try and get the money from the guests to replace all the white towels, sheets, linens, robes, etc which had blood spatter all over them. Instead, the very wonderful Customer Service rep I reached immediately offered to send me a certain sum of money to replace all of these bloody and soiled things (which were brand new, as I had only recently opened); his kind attention to my case and his supportive manner led to my decision to continue hosting on Airbnb after experiencing this Hitchcockian nightmare ('Psycho' movie reference here). Had I not reached such a fantastic human being, I might not be writing this now - I might have quit hosting right there and then (besides all of the blood everywhere, there were crumbs everywhere, coffee grounds everywhere - These people were unbelievably messy and inconsiderate).
So, it never hurts to call Airbnb first, just in case you get lucky and get an experienced, compassionate, empowered C/S Rep, like I did. Can't hurt, and might help. I do get the sense they want new hosts to make it, and not quit early on in horror and disgust.