Public health experts are growing alarmed about a lack of new funds from Congress to fight the Zika virus.

The White House this week said that it could not wait any longer for Congress to act, and shifted about $500 million in leftover Ebola funds over to fight Zika. But the White House said that is only a temporary solution, and raised pressure on congressional Republicans to fulfill the administration’s emergency request for $1.9 billion in new funds.

{mosads}Health experts say they are distressed that money is being taken away from Ebola efforts, an important need in its own right, and that Congress is not providing more to fight Zika, a mosquito-borne virus that, while mild for most people, is dangerous for pregnant women. The virus has been linked to serious birth defects in babies.

The lack of new funding now could mean the virus does more damage in the United States and leads to more babies with developmental problems due to small heads, known as microcephaly, experts said.

“I think it’s an absolute outrage that President Obama was forced to move Ebola money to the Zika response,” said Lawrence Gostin, a professor of global health law at Georgetown University and an adviser to the World Health Organization.

The virus is expected to ramp up in the U.S. as the weather gets warmer. Nine months after that, Gostin predicted: “There will be another congressional hearing, and you’ll have poor mothers with their microcephalic babies testifying before Congress, and the public will ask, ‘How did you let this happen?’”

The White House’s $1.9 billion request for funding would go to areas like mosquito control, rapid response teams to limit outbreaks of the virus, vaccine research, and aid to Puerto Rico, which is being hit especially hard by the virus.

“I definitely think additional funding is needed,” said Crystal Boddie, senior associate at the Center for Health Security at the University of Pittsburgh Medical Center. “I think it’s unfortunate that Congress hasn’t moved more quickly on this.”

One area experts point to is mosquito control, such as spraying insecticide and eliminating standing water where the insects breed. Since mosquito control is handled at the local level, different areas have vastly different levels of preparedness, which more federal funding could help remedy.

“We must be in a position to be able to handle 20-50 cases at a time,” said Dr. Jose Szapocznik, head of the University of Miami’s Department of Public Health. “That’s what no one is prepared to do now, and that’s why the president’s funding to fund mosquito control is so important.”

There is currently no vaccine for Zika, so another crucial area is vaccine research.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, said that without new money from Congress, he would have to divert funds from research on malaria, tuberculosis and a universal flu vaccine to have enough money for Zika vaccine research.

“If I don’t get the money, then I’m going to have to not do other things that are important in biomedical research,” Fauci said in an interview.

He said the transfer of Ebola funds announced this week “will keep me going for a little while,” but that it is not enough.

While congressional Republicans have not completely ruled out new Zika funding, they primarily hailed the White House for shifting Ebola funds this week, a move the administration had resisted.

And Speaker Paul Ryan (R-Wis.) said last month that the administration already had “plenty of money” to fight Zika.

Still, there was some movement on Friday, when Sen. Marco Rubio (R-Fla.), a high-profile figure and former presidential candidate, said he supports the White House’s request for $1.9 billion in funds.

He said he wants to ensure the funding is spent wisely and is not a “gravy train,” but indicated he would work to get his Republican colleagues to support it.

“I want to ensure that I work with my fellow Republicans in both the House and Senate to ensure that we’re doing everything we can to get my colleagues to be supportive of it,” Rubio said.

Florida is one of the states where Zika is expected to have the most impact.

It remains uncertain how widespread the Zika virus will be in the U.S., although it is widely expected to grow more prevalent as the weather gets warmer.

U.S. health officials have said that a widespread outbreak is unlikely, given their experience with other mosquito-borne viruses like dengue, that have been limited to small caseloads in places like Florida and Texas.

“We still feel that that is the very likely scenario,” Fauci said in the interview Thursday.

But he cautioned that “Zika seems to continue to surprise us a bit,” leaving open the possibility it could be more widespread than dengue.

For example, he noted that the virus can also be spread through sex and has the potential to get into the supply used for blood donations.

The White House is using the possibility of public panic, similar to the response seen to Ebola in 2014, to pressure Republicans. 

White House press secretary Josh Earnest said Wednesday the funding request is “going to seem pretty common sense if and when we reach the scenario where there is genuine public panic about the spread of this disease.”

“And again,” he added. “I take no joy in suggesting that Republicans are going to look back on this time that they’ve had to act on the Zika virus and deeply regret it.”