The infection, known as Zika fever or Zika virus disease, often causes no or only mild symptoms, similar to a very mild form of dengue fever.[3] While there is no specific treatment, paracetamol (acetaminophen) and rest may help with the symptoms.[5] As of 2016, the illness cannot be prevented by medications or vaccines.[5] Zika can also spread from a pregnant woman to her fetus. This can result in microcephaly, severe brain malformations, and other birth defects.[6][7] Zika infections in adults may result rarely in Guillain–Barré syndrome.[8]