WASHINGTON >> After a three-month delay, the Senate is acting on President Barack Obama’s request for money to combat the Zika virus.

The Senate is slated to vote today on three competing plans to battle the virus, with a bipartisan plan that cuts Obama’s $1.9 billion request to $1.1 billion having the greatest chance to advance. The procedural vote would pave the way to add funds for the government’s response to Zika to an unrelated spending bill.

For pregnant women, Zika can cause a serious birth defect called microcephaly and other severe fetal brain defects, as well as eye problems, hearing deficits and impaired growth. Zika is commonly spread by mosquitoes and can also be contracted through sexual contact.

The Centers for Disease Control and Prevention recommends that pregnant women not travel to areas with Zika and that if they live in a Zika area to strictly follow steps to prevent mosquito bites and to prevent sexual transmission.

Zika is expected to spread more widely during the summer mosquito season, but officials say outbreaks in the U.S. are likely to be limited. To date, there have been more than 500 cases of Zika in the continental U.S., all of which so far have been associated with overseas travel.

Obama requested the funding in February and has been forced to tap unspent 2015 funds from the successful battle against Ebola to finance almost $600 million in anti-Zika efforts. They include research on the virus and Zika-related birth defects, response teams to limit Zika’s spread, and helping other countries fight the virus.

The White House and its Democratic allies have been sharply critical of Republicans controlling Congress over delays in providing additional funds, which they say is required for mosquito control, purchasing diagnostic tests and developing and manufacturing a vaccine.

House Republicans on Monday unveiled their Zika proposal, which would slice Obama’s request to $622 million and pair it with offsetting spending cuts to unspent Ebola funding and leftover money at the Department of Health and Human Services. The House measure will advance as a stand-alone bill and it’s unclear how difficult it will be to forge a compromise between the two chambers.

“This funding is critical to stop the spread of Zika, and to protect our most vulnerable people both here at home and abroad. Every child deserves the chance at a full and healthy life, and every mother deserves to see her child thrive,” said House Appropriations Committee Chairman Harold Rogers, R-Ky.

But Rep. Nita Lowey of New York, the top Democrat on the panel, said the GOP proposal will delay work on vaccines and diagnostic testing and doesn’t provide enough money to control mosquitoes. “Pinching pennies on these basic investments will inevitably heighten costs — in dollars and lives — down the road,” Lowey said.

The bipartisan Senate measure was negotiated by Roy Blunt, R-Mo., and Patty Murray, D-Wash. It is relatively close to what the White House has asked for, except it does not pay back very much of the already-tapped Ebola money or give Puerto Rico, a Zika hot spot, help with its Medicaid program.

The administration is urging lawmakers to deliver additional anti-Zika funds before Congress recesses for Memorial Day. A more likely deadline is early to mid-July, when lawmakers leave Washington for a seven-week recess dictated by earlier-than-usual national political conventions.

An alternative Senate plan by Florida Democrat Bill Nelson and his home-state GOP colleague Marco Rubio that largely mirrors Obama’s request is unlikely to overcome a filibuster, as is a GOP proposal by Texas Sen. John Cornyn that taps a prevention fund established under the Affordable Care Act to offset the Zika funding.

“Let’s not be penny wise and pound foolish,” said Sen. Dick Durbin, D-Ill. “Cutting back on this money for pregnant women and running the risk that a baby born with a lifetime of medical challenges and expenses is no savings.”