The active transmission zone grew from 1.5 square miles to 4.5 square miles and consists of a large portion of the popular tourist destination, Florida Governor Rick Scott said in a statement on Friday evening, Reuters reports.
Miami Beach Mayor Philip Levine told the Miami Herald that the city will begin truck-spraying of larvicide in the zone on Saturday.
“We have a serious problem,” he told the newspaper. “Once again, we must take all reasonable and safe action to eliminate this. This is a problem.”
The zone was expanded after the Florida Department of Health identified five cases in the area involving three women and two men who all experienced symptoms within one month of each other.
The cases bring the total of non-travel related Zika cases in Florida to 93 and in Miami Beach to 35, the governor said.
Three weeks ago, federal health officials warned pregnant women not to travel to Miami Beach because Zika has been shown to cause the severe birth defect known as microcephaly, a condition marked by abnormally small head size that can result in developmental problems.