According to a report from ABC News, 19 people have been diagnosed in the continental United States with being infected with the Zika virus, which could cause a fever, rash, joint pain or conjunctivitis.
The CDC, which has not independently confirmed any cases in the continental United States, says nearly 20 percent of those infected show any symptoms. The disease has been spread from mosquitos carrying the virus from person to person.
In addition to 19 cases in the continental United States, there have also been 19 people infected in the U.S. territory of Puerto Rico. Of the 22 countries reporting cases, 20 are in the Americas.
According to the AP, health officials suspect Zika is linked to a wave of birth defects in Brazil in which babies have small heads. The CDC is recommending that pregnant women consider postponing trips to countries and areas in the Caribbean and South America where there are Zika virus disease outbreaks.
For the majority of people infected, the symptoms are mild and pass within a few days. Hospitalization is rare, according to the CDC.
Information from the Associated Press contributed to this report.