Fifth disease, also known as erythema infectiosum, is a viral illness caused by parvovirus B19. It is most common in children between the ages of 5 and 15, but adults can also get it. The virus spreads through droplets when an infected person coughs, sneezes, or touches a surface. The disease is characterized by a rash that starts on the cheeks, giving them a bright red appearance, which is why it is sometimes called a "slapped cheek" rash. The rash then spreads to the trunk, arms, and legs, and usually lasts 1 to 3 weeks. Other symptoms of fifth disease include a low fever, headache, and a stuffy or runny nose. Fifth disease is usually a mild illness that goes away on its own without treatment. Good hygiene, such as washing hands frequently and thoroughly, is the best way to prevent the disease from spreading. Pregnant women should avoid being near children with fifth disease, as the virus can harm an unborn child.