Health workers in Ivory Coast have begun giving children the latest malaria vaccine. It’s the beginning of a regional campaign that experts hope might curb the impact of one of Africa’s top killers. The West African country on Monday became the first to start rolling out the newest shot targeting malaria in a mass campaign that aims to cover about 250,000 children under two. More than 94% of the world’s roughly 249 million malaria cases and 608,000 deaths every year are in Africa. But since malaria vaccines don’t stop the disease from spreading, experts warn other measures like bed nets and insecticide spraying remain essential.