In early February, the Obama administration asked Congress to quickly pass nearly $1.9 billion in emergency funds. It trotted out public-health officials to explain what they knew about the virus’s potential effect in the Americas, and what they needed to develop: a vaccine, top-flight diagnostic tests, rapid-response teams for any Zika clusters that pop up in the United States, among other measures.

So far, Congress hasn’t allocated any new money. The White House grudgingly repurposed about $600 million in Ebola funds for Zika earlier this month, at House Republicans’ urging, but the administration and public-health officials maintain much more is needed. The number of cases in the continental United States and in the territories continues to grow. Scientists have confirmed the virus causes the birth defect microcephaly and the immune disorder Guillain-Barré, and are investigating a link between Zika and brain and spinal-cord infections. Officials are also concerned about the coming warmer months, particularly in warm-weather states. “Everything we look at with this virus seems to be a bit scarier than we initially thought,” said Anne Schuchat, the CDC’s principal deputy director, at a White House briefing two weeks ago.

Congressional Republicans have said for weeks now that their questions on Zika funding haven’t been answered—an allegation the White House and Senate Democrats have refuted. Specifically, Republicans say they need to know how much money is needed before the 2016 fiscal year ends in late September; how much is needed in fiscal year 2017; and, of course, how exactly it’ll be spent. John Cornyn, the Senate Majority Whip, cautioned Thursday against writing a “blank check” to the administration without hearing the Zika “plan of attack.”

Democrats have condemned the standstill. “Too many of my colleagues on the other side of the aisle still don’t seem to see Zika as an emergency,” Senator Patty Murray, the ranking member on the Senate Labor/HHS subcommittee, said Thursday. Some Republicans think it can wait “weeks, or even months,” she added. “Republicans in Congress might be able to wait that long—but families across the country simply can’t.”

Members of the House GOP have been especially, and predictably, hawkish about how money is doled out. House Majority Leader Kevin McCarthy has said the administration has enough money for Zika as it is. Some have suggested more money can be gleaned from Ebola coffers, and House Speaker Paul Ryan has said the White House has “a bit of a track record of over-requesting what they need.” Representative Tom Cole seemed to push back Thursday on the notion that Republicans are unnecessarily blocking funds. “I want to remind the White House, it was a Republican Congress that appropriated everything and more to combat Ebola just last year,” said Cole, the chairman of the House Appropriations subcommittee that finances public-health agencies, in a statement. “It was a Republican Congress that provided double the increase in funds for the National Institutes of Health requested by the White House. And it was a Republican Congress that appropriated more for the Centers for Disease Control than the White House requested.”