The U.S. government declared a state of emergency in Puerto Rico on Friday responding to widespread transmission of the Zika virus.
Following his visit to the island territory this week, U.S. Surgeon General Vivek Murthy predicted that one fourth of Puerto Rico's 3.5 million residents will be infected by the end of 2016.
Puerto Rico reported 1,914 new cases in the past week, bringing the total to 10,690 since the first case reported in December. More than 1, 000 of the total cases have been pregnant women.
But experts fear the real number of infections may be higher. As many as eight of 10 people show no symptoms when infected and thus would not go to the doctor.
The state of emergency, requested by Governor Alejandro Garcia Padilla, will allow the U.S. to allocate emergency funding to combat the virus in Puerto Rico, as well as deploy medical staff.
"Zika poses a hidden threat to future generations of Puerto Ricans, and I feel the responsibility to do everything in my power to fight the spread of it," Padilla said.
Although the virus is relatively mild in most cases, pregnant women who are infected with Zika risk giving birth to babies with a congenital defect called microcephaly, which causes an abnormally small head.