A 'dream' come true: Now there are 2 vaccines to slash the frightful toll of malaria

A Kenyan child receives the world's first malaria vaccine, approved nearly two years ago. This week, the World Health Organization approved a second vaccine for the mosquito-borne disease. It's called R21/Matrix-M and is intended for children between 5 and 36 months, who are among the most vulnerable to the disease. (Yasuyoshi Chiba /AFP via Getty Images)

"As a malaria researcher," says WHO Director-General Tedros Adhanom Ghebreyesus, "I used to dream of the day when we would have a safe and effective vaccine against malaria. Now we have two."

They're the first vaccines designed to work against a human parasite.