Officials are now investigating what might be 4 cases of Zika from a mosquito in Florida

An aedes aegypti mosquitoes is seen in The Gorgas Memorial institute for Health Studies laboratory as they conduct a research on preventing the spread of the Zika virus and other mosquito-borne diseases in Panama City February 4, 2016. REUTERS/Carlos Jasso

(An aedes aegypti mosquito.Thomson Reuters)

Florida is looking into four cases of what might be mosquito-transmitted Zika.

Florida's Department of Health confirmed Wednesday that it's investigating two cases of Zika in Miami-Dade County and two in Broward County that were not related to travel.

The department hasn't clarified whether that meant the case could have been contracted sexually, which has happened before in the US. The department also hasn't specified whether this meant the cases were caused by an infected mosquito.

"This pattern is consistent with other mosquito-borne virus investigations, such as the 2013 dengue response," the department said in a release. "The investigations into the new cases will begin today and door-to-door outreach and sample collection are ongoing in all cases. The department will share more details as they become available."

Zika, which is transmitted mainly by mosquitoes, has been spreading around the Americas over the past year, though local transmission by mosquitoes hasn't yet been reported in the US. Officials have warned that mosquito transmission could be possible in the US, especially in the summer months. Only about 20% of people who are infected with Zika ever show symptoms, which most commonly include fever, rash, joint pain, and red eyes. No vaccine or treatment is available for the virus.

Here's a map of all the places Zika has spread locally so far:

BI Graphic_Zika Virus Map And List (4)

(Dragan Radovanovic/Business Insider)

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