Authorities have detected Zika in mosquitoes in Miami Beach, the first time the insects have been found carrying the virus in the United States.
“These findings are very disappointing, but not surprising,” the Florida Department of Agriculture and Consumer Services said in a statement released on Thursday.
Officials had already suspected that the virus was being spread by mosquitoes locally following a recent outbreak of the virus in Miami.
The Centers for Disease Control and Prevention have warned pregnant women against travelling to Miami as the virus can cause birth defects.
Last week the US Food and Drug Administration also instructed blood banks across the country to screen donated blood for Zika.
According to WHO, Zika virus is a mosquito-borne flavivirus that was first identified in Uganda in 1947 in monkeys through a network that monitored yellow fever.
It was later identified in humans in 1952 in Uganda and the United Republic of Tanzania.
Outbreaks of Zika virus disease have been recorded in Africa, the Americas, Asia and the Pacific.
From the 1960s to 1980s, human infections were found across Africa and Asia, typically accompanied by mild illness.
The first large outbreak of disease caused by Zika infection was reported from the Island of Yap (Federated States of Micronesia) in 2007.
In July 2015 Brazil reported an association between Zika virus infection and Guillain-Barré syndrome.
In October 2015 Brazil reported an association between Zika virus infection and microcephaly.
The incubation period (the time from exposure to symptoms) of Zika virus disease is not clear, but is likely to be a few days.
The symptoms are similar to other arbovirus infections such as dengue, and include fever, skin rashes, conjunctivitis, muscle and joint pain, malaise, and headache. These symptoms are usually mild and last for 2-7 days.