A group of five Republican senators on Thursday introduced legislation that would restrict those who live in Ebola-stricken countries from traveling to the United States, while allowing exceptions for some aid workers and foreign military members.

People who live in countries designated by the Centers for Disease Control and Prevention as having “widespread transmission of Ebola” would not be able to receive a visa to enter the United States, under the bill. Aid workers and foreign military authorized by the United States Agency for International Development and the Defense Department would be exempt. 

“To protect our security, we must stop Ebola at its source,” Sen. Chuck GrassleyCharles (Chuck) Ernest GrassleyRepublicans jockey for position on immigration House clears bill to combat crimes against elderly Grassley: DACA deal wouldn't need border wall funding MORE (R-Iowa) said in a statement. “The best way to make this happen is to cease issuing visas or restricting entry to people from countries that are most impacted.”

Grassley added that, “these countries simply don’t have the standards in place to properly screen travelers entering the United States.”

He is joined by Republican Sens. Marco RubioMarco Antonio RubioOvernight Defense: Tillerson, Trump deny report of rift | Tillerson says he never considered resigning | Trump expresses 'total confidence' in secretary | Rubio asks Army to kick out West Point grad Rubio asks Army to kick out West Point grad with pro-communist posts GOP establishment doubts Bannon’s primary powers MORE (Fla.), Pat RobertsCharles (Pat) Patrick RobertsThe Hill's Whip List: Republicans try again on ObamaCare repeal No. 2 Senate Republican backs McConnell in Trump fight Overnight Healthcare: McConnell warns Senate not to block repeal debate | Insurers knock Cruz proposal | WH tries to discredit CBO | Lawmakers propose .1B NIH funding boost MORE (Kan.), John ThuneJohn Randolph ThuneGun proposal picks up GOP support Overnight Regulation: Senate panel approves driverless car bill | House bill to change joint-employer rule advances | Treasury to withdraw proposed estate tax rule | Feds delaying Obama methane leak rule Dems see Trump as potential ally on gun reform MORE (S.D.) and Mark KirkMark KirkGiffords, Scalise highlight party differences on guns Stale, misguided, divisive: minimum wage can't win elections Immigration critics find their champion in Trump MORE (Ill.). All five senators, along with a slew of other lawmakers, have previously called for a travel ban. But the White House has resisted those calls and said that a ban could be counterproductive, encouraging travelers to lie about exposure to the virus.

Citing State Department figures, Grassley noted that the U.S. issued more than 6,300 visas to people from Liberia, Sierra Leone and Guinea from March until September 27. Those three countries would meet the guidelines for a travel ban under the bill and have been battling the current Ebola outbreak since March. 

Residents would be able to receive visas 60 days after the CDC says the virus is no longer rampant in their home country.