Slapped cheek disease is a viral infection that mainly affects primary-school-aged children. It results from being infected with human parvovirus B19. It causes a bright red rash on the cheeks, which look as though they have been slapped – hence the name.
Like many viral infections, it is spread by mucus from an infected person when sneezing or coughing. This mucus is carried by hand to the mouth or nose of another person.
The incubation period for slapped cheek disease is usually between four and 14 days after contact (in rare cases, up to 21 days). This infection is also called slapped face disease, slapped cheek syndrome, fifth disease or erythema infectiosum.
For most children, infection with slapped cheek disease initially causes little more than cold symptoms. These generally improve after a few days, when the rash starts to show.
Most people with slapped cheek infection need little if any treatment. Rest and pain-relieving medication (such as paracetamol) may help.
The infection can be more serious for pregnant women. Rarely, if a pregnant woman gets this infection, there can be serious consequences to her unborn child, including miscarriage. Most unborn babies are not affected, even when they get this infection.
Symptoms of slapped cheek disease
The first symptoms seem like a cold and can include:
- aching muscles
- sore throat
- runny nose, coughing and sneezing.
As these cold-like symptoms start to improve, the rash on the face appears. This rash is bright red, 'lacy' (with patches of normal coloured skin within the red areas) and often itchy. The person may also develop a pink blotchy rash on the limbs or torso after a few days. Many people (up to 20 per cent) do not have any symptoms at all when they have the infection.
Symptoms of slapped cheek disease for teenagers and adults
Arthritis-like symptoms, such as swollen ankle, knee and wrist joints, are common for teenagers and adults with slapped cheek disease. This complication is more common in female teenagers and adults, and is sometimes the only symptom of infection.
Normally, it takes around two to four weeks for the joints to get better. However, in some people, the swelling can last for months. Unlike true arthritis, there is no danger of permanent damage, even if the joints are affected for a long time.
Parvovirus B19 and slapped cheek disease
Parvovirus is a virus that lives in red blood cells. It can only infect humans and is different from dog or cat parvoviruses.
Children between the ages of five and 15 years are prone to contracting the disease. Adults who have regular contact with children, such as teachers and child healthcare workers, are also at increased risk. However, over half of all adults are immune to the virus because they had the infection in childhood.
People are infectious during the incubation period, which is usually about a week before the rash appears. Once the characteristic rash has appeared, the person is no longer contagious. This pink, lace-patterned rash tends to last for around one to three weeks, and is made more obvious by exercise, sunlight or hot weather.
Groups at high risk for slapped cheek disease
Generally, the slapped cheek virus is a mild illness that doesn’t pose any health risks to the sufferer. However, contracting the virus is serious for people with specific conditions such as pregnancy, weakened immunity and haemolytic blood disorders.
Pregnancy and slapped cheek disease
In Victoria, about 60 per cent of women aged 20 to 39 will have had the infection before their pregnancy and will be immune. Some will get it while they are pregnant (between 1.5 and 15 per cent of women of child-bearing age in Victoria contract the infection each year).
The risk to unborn babies is low. Even if the mother is affected, only one-third of babies will develop the infection (generally about a month after the mother's illness).
A pregnant woman who believes she has been in contact with a case of parvovirus infection should consult the doctor supervising her pregnancy, even if she has no symptoms.
If a woman who is pregnant gets the infection, her baby’s development will need to be monitored (for example, by ultrasound).
In rare cases, infection during the first 20 weeks of pregnancy can cause a form of anaemia (low blood count) in the baby. In many cases, this resolves by itself, but in about five per cent of cases it may require treatment. Very rarely, it can cause a miscarriage or stillbirth. Parvovirus infection does not cause birth defects.
Weakened immunity and slapped cheek disease
People with compromised immune systems (for example, people being treated for cancer or severe asthma, or those with HIV/AIDS) can develop chronic and severe anaemia with slapped cheek disease. They may require a transfusion of red blood cells to maintain an adequate level of haemoglobin.
Haemolytic blood disorders and slapped cheek disease
Those with disorders such as sickle cell anaemia, thalassaemia and hereditary spherocytosis can experience a sudden drop in haemoglobin, the protein that transports oxygen around the blood, with slapped cheek disease. In severe cases, this can lead to heart failure. A transfusion of red blood cells to maintain an adequate level of haemoglobin may be required.
Where to get help