Medically reviewed by Anju Goel, MD Key Takeaways Diarrhea is often contagious, especially when it's caused by viruses, bacteria, or parasites. Infectious diarrhea can spread by not washing hands ...

Meningococcal meningitis spreads through saliva and requires close contact. Viral meningitis can be caused by viruses like the measles virus and chickenpox. Fungal meningitis can occur when a fungus ...