A fourth case of the Zika virus has been reported in Illinois, the Illinois Department of Public Health said in a statement on its website.
IDPH told NBC Chicago a woman who is not pregnant has the virus. Further details about her age or her travel history were not disclosed.
Most people exposed to Zika, a tropical virus spread by mosquitoes, suffer only mild symptoms. But the risk is far greater for pregnant women because of a possible link to a birth defect and neurological problems.
Federal health officials have posted Zika travel notices about countries in Central and South America and in the Caribbean. Also: Cape Verde, off the coast of western Africa, and Samoa in the South Pacific.
The CDC recommends pregnant women in any trimester should consider postponing travel to the areas where the Zika virus transmission is ongoing.
The IDPH recommends anyone who does travel uses an insect repellent, wears long sleeves and pants, and stays in places with air conditioning or window and door screens.
Symptoms including fever, rash, joint pain, or conjunctivitis can last from several days to weeks and there is no vaccine to prevent or treat an infection.
