Causes

The human parvovirus B19 causes parvovirus infection. This is different from the parvovirus seen in dogs and cats, so you can't get the infection from a pet or vice versa.

Human parvovirus infection is most common among elementary school-age children during outbreaks in the winter and spring months, but anyone can become ill with it anytime of the year. It spreads from person to person, just like a cold, often through breathing, coughing and saliva, so it can spread through close contact between people and hand-to-hand contact.

Parvovirus infection can also spread through blood. An infected pregnant woman can pass the virus to her baby.

The illness is contagious in the week before the rash appears. Once the rash appears, you or your child are no longer considered contagious and don't need to be isolated.