The Zika virus is about to become an emergency in the United States and immediate action is necessary to fight the disease, U.S. Sen. Christopher Murphy said Wednesday.

President Barack Obama has asked for $1.9 billion to combat Zika and the mosquitoes that carry the virus, but the Republican-controlled Senate has refused to act on the bill, Murphy said in a conference call, along with U.S. Sens. Ben Nelson, D-Fla., and Charles Schumer, D-N.Y., Dr. Peter Hotez, dean of Baylor College of Medicine’s National School of Tropical Medicine, and Ron Klain, who coordinated federal response to the Ebola outbreak.

Zika has been linked to microcephaly, which causes abnormally small heads and underdeveloped brains in newborns.

“Why would you want to wait until you have a baby born with this defect when we can spend money now to prevent this outbreak?” Murphy said. “To me it’s so disappointing because this virus isn’t a Democratic virus; it’s not a Republican virus. It affects everything.”

“It used to be that we could work together. We need to sit down together, Republicans and Democrats, and appropriate this money now,” Murphy said.

The senators pointed out that $4 billion was approved to fight the Ebola virus, which helped to prevent a major outbreak in this country. Republicans have called for money in the Ebola fund to be used against Zika, and $600 million has been redirected, but they said the full $1.9 billion is needed.

“We all know the Zika virus is a ticking time bomb and the way to defuse it is to give the funding that they need,” Schumer said. “Let’s protect ourselves from Zika now before it’s too late.

Republicans have said they are likely to vote on an appropriation for Zika but action is not likely before September, according to the Associated Press.

On the House side, U.S. Rep. Rosa L. DeLauro, D-3, proposed an amendment to an agriculture appropriations bill Tuesday asking for $1.9 billion, including $1.5 billion for the Department of Health and Human Services. Nelson said the virus has spread to 40 states — nearly all because of travelers returning from countries where the virus is rampant, including Brazil, Colombia and Haiti. He said there have been 91 cases so far in Florida, including five pregnant women, but none of them was infected in this country.

Nelson said “we had a little victory yesterday, with legislation that gives a “financial incentive to drug companies to come up with a vaccine. … Even with that incentive it’s still going to take some time for those pharmaceutical companies to develop the drug.”

Meriden’s Protein Sciences Corp. is part of a consortium to develop a Zika vaccine.

“Clearly the World Health Organization has said this is a public health emergency of international concern,” Nelson said. “We’ve got a full-blown crisis.”

Murphy said of the Democratic senators that “We are united in our belief that Republican leadership must bring a Zika funding bill to the Senate floor as soon as possible. Every day that Republican leadership waits to act on Zika funding the threat gets bigger.”

Murphy added that Senate Majority Leader Mitch McConnell, R-Ky., “said he wouldn’t rule out acting on Zika but it might be later in the year. There seems to be a casualness … Why on Earth wouldn’t you have a sense of urgency?”

As of April 13, the Centers for Disease Control and Prevention reported 358 cases of Zika in the United States, all of them acquired as the result of traveling to other countries. Zika is spread by two species of mosquitos, the most common being the Aedes aegypti, which only feeds on humans.

Its symptoms are similar to a mild flu, but the virus has a devastating impact on developing fetuses. “Although we call in microcephaly, it’s not just having a small head,” said Hotez. “It’s essentially blocking the development of the brain. … This is the virus from hell.”

Hotez said, “We already know it’s going to occur in Puerto Rico” and “as we speak it’s decimating Haiti,” which has no sanitation system to speak of. Population density and poverty are two factors that favor the spread of Zika, because of poor drainage and inadequate window screens, among other things.

In this case “the most vulnerable areas … are the U.S. Gulf Coast” and all of Florida, Hotez said. “These are not easy mosquitos to control,” he said. “It’s labor intensive, it’s hard work and it needs funding.”

Klain said that when Obama requested $6 billion to fight Ebola the day after Election Day 2014, “We got 90 percent of the money we asked for. We got a lot of flexibility.” The president requested money to fight Zika in February and “this time it’s been very different,” Klain said. “There’s been a lot of pushback on it.”

Republicans so far have been adamant about redirecting money from the Ebola fund but Klain said the $600,000 is not enough. “We need all of that funding and we need it now,” he said.