Senate Democrats last week blocked a bill that would have provided $1.1 billion for research and prevention of Zika virus transmission in the U.S. The move makes it unlikely that new funding will be provided before the mosquito-borne virus takes hold in the U.S., which is expected this summer. Congress is taking a seven-week break starting in mid-July. Zika is known to cause birth defects in some babies whose mothers contract the virus while pregnant, but more research is needed to determine when pregnant women are most at risk. Democrats and President Barack Obama support even higher Zika funding—the White House asked for $1.9 billion—but they objected to attachments that would limit women’s access to birth control and extend use of pesticides. They also balked at how the bill was funded. The Republican-authored bill, which had already passed in the House of Representatives, would take money away from Ebola research and from the Affordable Care Act implementation. Republicans, in turn, said Democrats would be to blame for any children born in the U.S. with birth defects.