Another diplomat working at the United States Embassy in Havana has been sickened by a mysterious attack, bringing to 25 the number of personnel who have fallen ill there, the State Department said on Thursday. The case was the first confirmed in Cuba since August and could suggest that whatever caused the illnesses in late 2016 and the first part of 2017 had started again or was continuing. Complicating the situation for officials was news this spring that at least one diplomat at a consulate in Guangzhou, China, had experienced symptoms almost identical to those reported by diplomats in Havana....