The Centers for Disease Control and Prevention say doctors should ask pregnant patients about their travel and certain symptoms, and—if warranted—test them for Zika.
The new guidelines released Tuesday by the CDC recommend pregnant women postpone travel to any of the 14 countries and territories in Central and South America and the Caribbean where transmission of the vector-borne disease is currently active.
Healthcare providers should ask all pregnant women about recent travel to an affected area, the CDC advises. They should evaluate any potentially at-risk patients for signs of possible transmission of the disease.
The virus is spread through mosquito bites but there's no risk of person-to-person spread. Outbreaks have been reported in parts of the Caribbean and Latin America. In Brazil, there's evidence linking the infection to microcephaly, a serious birth defect in which an infant is born with a head significantly smaller than normal.
On Friday, the CDC issued a general travel alert for Brazil, Colombia, El Salvador, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Suriname, Venezuela and Puerto Rico. This came days after health officials in Texas confirmed the first U.S. case of Zika virus in a woman who had recently traveled to Latin America.
The CDC and health officials in Hawaii on Saturday confirmed the first U.S. case of a baby born with microcephaly was infected by Zika while in utero.
Two pregnant women from Illinois have tested positive for the virus after traveling in Honduras and Haiti.
The Illinois Department of Public Health said Tuesday doctors are monitoring the women's health and their pregnancies.
Doctors treating pregnant women who test positive for the disease are advised to administer ultrasounds every three to four weeks to monitor fetal growth.
There is no cure or vaccine for Zika virus, which is simply treated to alleviate symptoms.
Brazil has been hit hardest by the virus and its aftermath. The number of those infected is estimated at 1.5 million with as many as 3,500 cases of babies born with microcephaly since October.