Most people with parvovirus infection have no signs or symptoms. When symptoms do appear, they vary greatly depending on the age of the person who has the disease.

Parvovirus symptoms in children

Early signs and symptoms of parvovirus infection in children may include:

• Fever
• Upset stomach
• Headache
• Runny nose

Distinctive facial rash

Several days after the appearance of early symptoms, a distinctive bright red facial rash may appear — usually on both cheeks. Eventually it may extend to the arms, trunk, thighs and buttocks, where the rash has a pink, lacy, slightly raised appearance. The rash may be itchy, especially on the soles of the feet.

Generally, the rash occurs near the end of the illness. It's possible to mistake the rash for other viral rashes or a medicine-related rash. The rash may come and go for up to three weeks, becoming more visible when a child is exposed to extreme temperatures or spends time in the sun.

Parvovirus symptoms in adults

Adults don't usually develop the slapped-cheek rash. Instead, the most prominent symptom of parvovirus infection in adults is joint soreness, lasting days to weeks. Joints most commonly affected are the hands, wrists, knees and ankles.

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 respiratory secretions and hand-to-hand contact.

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

The illness is contagious in the week before the rash appears. Once the rash appears, the person with the illness is no longer considered contagious and doesn't need to be isolated.

Parvovirus and anemia

Parvovirus infection can cause serious complications for people with anemia, a condition in which red blood cells, which carry oxygen to all the parts of your body, are used up faster than your bone marrow can replace them. Parvovirus infection in people with anemia may stop the production of red blood cells and cause an anemia crisis. People with sickle cell anemia are at particular risk.

Parvovirus can also cause anemia and related complications in:

• The unborn children of women infected with parvovirus during pregnancy
• People who have weakened immune systems

Parvovirus infection in pregnancy

Parvovirus infection during pregnancy sometimes affects red blood cells in the fetus. Although uncommon, this may cause severe anemia that could lead to miscarriage or stillbirth. Fetal risk appears greatest during the first half of the pregnancy.

Parvovirus in people with weakened immune systems

Parvovirus infection can also trigger severe anemia in people who have compromised immune systems, which may result from:

• HIV infection
• Cancer treatments
• Anti-rejection drugs used after organ transplants