A ‘forgotten disease’ is suddenly causing new worries

The world is in danger of running out of vaccines for a deadly disease: yellow fever. A major outbreak in the African nation of Angola has already depleted the stockpile that world health officials had set aside for emergencies. It’s unclear whether new vaccines can be made in time — even as officials worry that the epidemic could spread through Asia and beyond. Yellow fever itself is part of America’s history. The mosquito-borne virus was a dreaded killer in the United States through the early 1900s — sparking devastating epidemics in Philadelphia and New Orleans. The disease has been all but eradicated in wealthy countries but remains a serious threat in areas of Africa and South America where it still pops up. “You first feel a little achy and then there is a sudden onset of fever, the malaise and then there’s these headaches,” says Ilhem Messaoudi, an infectious disease specialist at...