The Zika virus, which has swept through the Americas and Caribbean since last fall, has been linked to thousands of cases of microcephaly, a rare birth defect, in Brazil, as well as to neurological disorders. Photograph: Felipe Dana/AP US lawmakers deadlocked over funding to fight the Zika virus on Tuesday, as Senate Democrats blocked a Republican proposal they said fell short of the challenge posed by the mosquito-borne virus and hurt other health priorities. Amid political recriminations by both parties, the Republican plan to provide $1.1bn in funding to combat Zika, which had already passed the House of Representatives, failed to get the 60 votes needed in the Senate to clear a procedural hurdle.