A municipal worker fumigates an alley in an impoverished area to prevent the spread of mosquito-borne diseases in New Delhi, India, Friday, Sept. 2, 2016. Scientists trying to predict the future path of Zika say that 2.6 billion people living in parts of Asia and Africa could be at risk of infection, based on a new analysis of travel, climate and mosquito patterns in those regions. Some of the most vulnerable countries include India, China, the Philippines, Indonesia, Nigeria, Vietnam, Pakistan and Bangladesh, according to the research. (AP Photo/Manish Swarup)