Around 600,000 but the numbers have varied greatly some saying it was more than 1,000,000 who died but the first one has shown to be the most likely
The Columbian Exchange had positive and negative consequences.
Some of the positive consequences were the introduction of different nutrients and food supplies into the Old World, such as corn or potatoes. This improved the diet of most Europeans, leading to a population growth in the next generations.
However, Europe benefited more than the Americas, for some of the negative consequences about the Columbian Exchange were the introduction of diseases into the continent and the slavery of African populations into the Americas.