Mad Cow Disease....... New person here, can't see how to answer question, so will just edit: Listeria comes to mind as well.
Ignorance
Ticks are often harmful to humans. For instance, the sheep tick could cause Lyme disease in humans.
Einsteinium is extremely radioactive and dangerous.
No, amoeba is not harmful to humans. The only amoeba that is harmful is Naegleria fowleri, however, it is extremely rare.
Yes, it is extremely toxic to both humans and animals.
It is unlikely, but in theory any animal might carry a disease that could be harmful to humans.
Bees don't carry any diseases that are harmful to humans but they can carry diseases that are harmful to other bees.
The Tasmanian Devil Facial Tumour Disease (DFTD) poses no risk at all to humans or animals of any other species.
Prion
The word pathogenic means disease causing. So they can be harmful...but some pathogenic bacteria only are harmful to plants or dogs or cats, etc.
Prions are infectious proteins. Examples are the well known "mad cow disease" or bovine spongiform encephalopathy (BSE; affects cattle), scrapie (affects sheep), Creutzfeldt-Jacob disease, Kuru, Gerstmann-Sträussler-Scheinker syndrome, and Fatal familial insomnia. Variant Creutzfeldt-Jakob disease (vCJD) is the disease that occurs in humans when BSE proteins from cattle enter humans.
The fires can burn down their property and the smoke can be extremely harmful, possibly fatal, if inhaled