Terrible Diseases

Why do mosquitoes spread so many diseases (e.g. Malaria, Dengue, Chikungunya, Zika)?

  But it's not the mosquito's fault (not all their fault, anyway). It's actually bacteria that's the cause of the disease, and mosquitoes are the ones that pass it from person to person. For example, The Plasmodium Parasite (not a bacteria!) is the cause of Malaria, and the Anopheles Mosquito spreads it.

  So you can tell that mosquitoes are bad. But there's another disease- called Schistosomiasis, that's carried by SNAILS (really!) - and it's gigantic.

  There are many diseases spread by animals, but there's a lot of diseases that humans have that are equally as bad as Malaria (e.g. Stroke, Heart Attack, Cancer, HIV/AIDS).