Senators Tom Carper (D) and Chris Coons (D) have signed on to a letter urging Republican leaders to call Congress back in session to fund an emergency response to the Zika virus.
Carper and Coons join 39 other Democrats in the letter to House Speaker Paul Ryan (R-WI) and Senate Majority Leader Mitch McConnell (R-KY) amid the longest recess Congress has taken in the last 60 years.
Republicans have balked at a $2 billion funding package from President Obama.
In response, they crafted a $1.1 billion proposal that Senate Democrats blocked – partially because it relied on draining an emergency account set up to respond to any threats from the Ebola virus.
This week, administration officials told Congress clinical trials on a Zika vaccine will be delayed if extra funding isn’t approved.
The virus is especially concerning for pregnant women. Evidence shows Zika can cause microcephaly in fetuses, which is a severe birth defect that shrinks the size of a baby's head and can lead to significant developmental problems.
At least six people have been infected with Zika in Florida by mosquito bites according to the Centers for Disease Control and Prevention with nearly 5,500 confirmed cases in Puerto Rico.
10 cases have been confirmed in Delaware, but each person was infected while traveling abroad.
People are cautioned to use mosquito repellant and protective clothing, as well as to potentially delay traveling to countries with high transmission rates.
The virus can also be spread through sex. Health experts say men and women should use condoms or another barrier method for six months after returning from countries with Zika outbreaks.
