Urging Congress to provide more resources in the fight against Zika, a top federal health official on Wednesday warned Congress that the virus is likely to spread into tropical areas of the United States such as Puerto Rico and South Florida, where the Aedes aegypti mosquito is common. Centers for Disease Control and Prevention Director Thomas Frieden told members of the Foreign Affairs Committee that the number of U.S. Zika cases has risen and cautioned that if the virus takes root, it could spread as rapidly as the chikungunya virus did in 2014,

when the disease, also carried by mosquitoes, crisscrossed Puerto Rico in less than a year. Acknowledging that a case of Zika was spread through sexual contact in Dallas, Frieden said much was still unknown about the virus, including the depth of its health effects and how long it could survive in bodily fluids. He said mosquito eradication remained the best way to fight the virus. READ MORE