By Toni Clarke
(Reuters) - Florida health officials have found evidence of likely local Zika transmission in Miami Beach, one of the world's most popular tourist destinations, opening a new front in the fight against the mosquito-borne virus, media reports said on Thursday.
A cluster of Zika cases have been identified and health officials are deciding whether to warn pregnant women against travel to the area, the New York Times reported, citing an unnamed health official.
The virus, which has spread rapidly through the Americas since it was first detected in Brazil last year, can cause the rare birth defect microcephaly, marked by abnormally small heads and developmental problems.
Florida's Department of Health would not confirm reports that Zika had spread to Miami Beach after being confirmed in the city's Wynwood neighborhood, the first site of local transmission in the continental United States.
"The department still believes active transmissions are still only occurring in the area that is less than one square mile in Miami-Dade County," said Mara Gambineri, a spokeswoman for the department, referring to Wynwood. "If investigations reveal additional areas of likely active transmission, the department will announce a defined area of concern."
The department on Thursday said there are 35 cases of likely local transmission in the state. The tally includes two new cases that were identified outside of Wynwood.
Officials are expected to identify a specific geographic area for ongoing Zika transmission within Miami Beach, the Miami Herald reported, citing unnamed sources.
City officials in Miami Beach were not available. The U.S. Centers for Disease Control and Prevention referred calls to state health officials.
The prospect of the virus spreading to the tourism-dependent Miami Beach area is likely to alarm tourism officials.
Last year, some 15.5 million people spent at least one night in Greater Miami and the beaches, generating nearly $24.4 billion in direct expenditures, according to the Greater Miami Convention & Visitors Bureau. More than 48 percent of all visitors stayed in Miami Beach.
Dr. Amesh Adalja, an expert in infectious diseases at the University of Pittsburgh Medical Center, said it would not be surprising to see new clusters of Zika cases pop up in different areas or counties of Florida. Local mosquito populations could pick up the virus from a person returning from another area where Zika is active.
He said it is important to alert people as soon as possible if local transmission is occurring so that pregnant women can protect themselves and get tested for the virus.
"You want to make sure that there's reasonable evidence that local transmission is actually occurring," Adalja said. "You don't want to jump to conclusions right away and cause people to panic or stigmatize an area that doesn't have local transmission."
Earlier this month Florida began aerial spraying of insecticides to kill mosquitoes in the Wynwood neighborhood. The CDC also issued an unprecedented warning to pregnant women and their partners to avoid the area.
Miami Beach public works officials and code compliance officers spread out on Thursday to inspect neighborhoods for mosquito breeding sites, the Miami Herald reported.
The Zika virus has been linked to more than 1,700 cases of microcephaly in Brazil, raising alarm among public health officials globally about its spread. The virus can also be spread through sex, making it unique among mosquito-borne diseases.
President Barack Obama in February requested $1.9 billion to fight Zika but Congressional efforts to approve part of the funding deadlocked before lawmakers adjourned for the summer.
(Reporting by Toni Clarke in Washington; Additional reporting by Letitia Stein in Tampa and Zachary Fagenson in Miami; Editing by Michele Gershberg and Bernard Orr)