Which disease was the most deadly out of all the diseases that Christopher Columbus brought to the Americas?

The deadliest disease that Christopher Columbus brought over the was the measles. The measles a virus that can be transferred through touch, cough, or by pregnant mothers. The measles is a rash that covers the body that can and more than will follow with a runny nose, cough, sore throat, inflamed eyes, or fevers. This was very deadly in the 1800’s, but now can be treated by a vaccine.