Michele Barry and Katherine States Burke

Zika has arrived in the United States, spreading via our own homegrown mosquitoes. And that is a game-changer.

The Centers for Disease Control has confirmed 14 cases in the Miami area that were almost certainly contracted through the bite of locally infected mosquitoes, and the number is climbing fast. President Obama has dispatched CDC teams to Florida to marshal the public health response. Federal officials are advising a travel ban for pregnant women in the area north of Miami.

As this crisis unfolds, where is Congress? On vacation.

Nationally, CDC reports more than 1,600 cases of imported Zika in 46 states and D.C., including more than 400 pregnant infected women. The situation is even worse in Puerto Rico, a U.S. territory that is failing to control an exploding epidemic. Thousands of people — including up to 50 pregnant women — are becoming infected there each day. Men can carry the virus for more than two months after an infection, thus ensuring sexual transmission as well as mosquito-borne disease.

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As in South America, the poorest and most vulnerable — those who live in socially disadvantaged areas where mosquitoes can easily breed in discarded tires, cans and tiny pools of water — are becoming infected in large numbers. These neighborhoods have little access to air conditioning or screens. Insecticide-impregnated bed nets are of little use since the mosquito that spreads Zika is most active in daytime. While Miami may garner the resources to control its epidemics, Puerto Rico will see the births of hundreds of microcephalic children.

As global warming and shifting weather patterns change the distribution of mosquito vectors, pandemics are accelerating. Emerging diseases, as well as existing threats such as dengue fever, are reaching new populations without immunity. Disease can spread like wildfire, as we have seen with Zika. The U.S. has a public health infrastructure second to none, and yet we are seeing it falter, hamstrung by partisan politics.

The science to control Zika is agonizingly close to readiness. Already, one vaccine candidate has been approved for early-stage human trials and several more are in the pipeline. Genetically modified mosquitos that can prevent transmission have been tried successfully in small geographic areas. But money is urgently needed to ramp these efforts up. Yet Congress left town with this work undone.

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Political conflicts left hanging a $1.9 billion bill to fund Zika research, prevention and education. Democrats objected to “poison pill” attachments reducing the role of Planned Parenthood in providing contraceptive services to fight sexual transmission of Zika, as well as others cutting Affordable Care Act financing and rescinding a ban on flying the Confederate flag in federal cemeteries.

On this important health matter, Congress has failed us. Its political concerns pale beside the prospect of hundreds of babies born with severe birth defects — a lifetime of agony for them and their families. In addition, absent the public health campaign that the bill would have funded, media and social networks will no doubt ignite outsized public fears, as we saw with the Ebola threat.

It’s time for the grown-ups to come back to the table. Senate Democratic Leader Harry Reid and Sen. Richard Blumenthal, D-Conn., have called for the House and Senate to return to Washington and reconvene on an urgent basis to provide the Zika funding. Republican leadership should join the effort. Funding the battle against Zika is imperative, and the American people are watching and waiting.

Michele Barry, a past president of the American Society of Tropical Diseases and Hygiene, is director of the Center for Innovation in Global Health at Stanford University.​ Katherine States Burke is the center’s deputy director.

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