The mosquitoes that changed history

In just the most recent example, mosquitoes are spreading the Zika virus throughout South and Central Americas, causing an increased incidence of birth defects.

However, the species of mosquito that carries the virus is endemic to Africa. So how did it travel across the ocean?

"The slave trade," according to John McNeill, a history professor at Georgetown and author of the book, "Mosquito Empires."

In fact, the species, Aedes Aegypti, is one of only three species of mosquito known to transmit disease among humans -- that's three of 3,500 different species, according to the CDC.