A single virus has infected almost every human on Earth
Anatomy
This master of disguise hides in the immune systems of 95 percent of adults, waiting for a moment of physical weakness to trigger life-threatening complications.
The Epstein-Barr virus is so successful that it has established a permanent home in nearly every person on the planet. Unlike most pathogens that struggle to find a way into our cells, this virus has evolved a specialized protein called gp42 that acts like a skeleton key, specifically unlocking the B cells of the human immune system. Once inside, it remains for life, usually dormant but always present.