The Centers for Disease Control and Prevention on Monday took the unusual step of advising pregnant women to avoid a section of Miami where the Zika virus appears to be spreading by mosquito bite, after the tally of known infections from the square-mile zone jumped from four to 14 in just three days.
Agency officials said pregnant women who traveled to the affected area on or after June 15 should be tested for Zika because the disease is known to cause serious birth defects in babies born to infected mothers.
It also urged men and women who have been through the neighborhood to wait at least eight weeks before trying to conceive a child.
CDC Director Thomas R. Frieden said aggressive mosquito control efforts in the block just north of downtown “don’t seem to be working as well as we’d liked,” fueling in part its decision to advise pregnant women to steer clear of a part of the continental U.S.
“As far as we know, we can find no similar recommendation in recent years,” Dr. Frieden said.
Eight members of a CDC emergency response team will help Florida officials investigate new cases and collect mosquito samples.
Gov. Rick Scott, a Republican, requested additional federal resources to deal with the 10 newly discovered cases through mosquito bite.
Those cases were found in the same Miami-Dade County neighborhood as the four he announced Friday, marking the first cases of locally acquired Zika on the U.S. mainland.
Until last week, the CDC was able to link more than 1,650 Zika cases in the states and District of Columbia to people who had returned from countries where the virus is circulating, plus one case of accidental laboratory infection. The disease is spreading on its own in Puerto Rico.
White House deputy press secretary Eric Schultz said the CDC has given Florida $2 million in Zika-specific response funding, plus $27 million in emergency preparedness funding — much of which can be used for the state’s Zika response.
He also said a decision by Congress not to fund further Zika prevention efforts hindered the administration’s ability to fund more research and slowed the development of a vaccine for Zika.
Republicans in Congress say Senate Democrats are to blame for blocking a $1.1 billion Zika deal that took $750 million from elsewhere in the federal budget and kept Planned Parenthood out of its contraception plans.
Amid the impasse, Republican leaders are urging the administration to spend down $589 million that it shifted from the Ebola fight and other accounts to combat Zika.
“That money needs to be allocated to programs in Florida and Puerto Rico today. There is no more time for delay,” said Rep. Ileana Ros-Lehtinen, a Florida Republican whose district is just south of the affected area and thus at high risk of further natural spreading.
Scientists had long expected local transmission in Southern states including Florida, based on small outbreaks of related viruses such dengue fever and chikungunya. Yet Zika is hard to detect because four out of five infected people don’t show symptoms.
State officials said six of the 10 new Miami patients were asymptomatic and were identified only from door-to-door outreach in the affected area.
“We may well see other infections in that area because of how efficient a vector this mosquito is,” Dr. Frieden said.
Disease-carrying Aedes mosquitoes in the affected area have been difficult to eradicate because they are either resistant to the insecticide that local officials use or are breeding in hard-to-reach areas of standing water, Dr. Frieden said.
He said the affected block, which includes the artsy Wynwood neighborhood, mixes high-end buildings and nightlife hot spots with economically distressed and isolated zones. That makes mosquito control even more difficult because methods must be tailored to each type of area.
Mindful of his state’s vital tourist industry, Mr. Scott said Florida “remains safe and open for business.”
“Florida has a proven track record of success when it comes to managing similar mosquito-borne viruses,” the governor said. “We will continue to keep our residents and visitors safe utilizing constant surveillance and aggressive strategies, such as increased mosquito spraying, that have allowed our state to fight similar viruses.”
But he urged women who are even thinking about having a child to avoid unnecessary travel to the affected area of Miami, which is tucked between Interstate 95 and U.S. Highway 1.
Some people aren’t taking the warnings seriously. On a CDC conference call, a reporter told Dr. Frieden that a pregnant woman in the affected zone told him she planned to ignore the government’s advice.
Dr. Frieden said that attitude is unfortunate, given the birth defects associated with the disease, though it is something the CDC has seen “surprisingly often in the Zika response.”
“I’m sorry that people feel that way,” he said, “but it is a problem.”
• Dave Boyer contributed to this article.
• Tom Howell Jr. can be reached at thowell@washingtontimes.com.
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