ConditionChildren's health
Fifth Disease (Slapped Cheek Syndrome)
Fifth disease is a common, usually mild viral illness caused by parvovirus B19. In children it starts like a cold, then a bright red rash appears on both cheeks, as if they had been slapped, followed by a lacy rash on the body. By the time the rash shows, the child is no longer contagious. Adults more often get painful joints. It needs no treatment in healthy people, but it matters in pregnancy and for people with sickle cell disease or a weak immune system.
Also called: Erythema infectiosum, slapped cheek syndrome, slapped cheek disease, parvovirus B19 infection
At a glance
- Cause
- Parvovirus B19, spread through respiratory droplets and, rarely, blood.
- Who gets it
- Mostly children aged 5 to 15, often in late winter and spring outbreaks.
- Key sign
- Bright red cheeks, then a lacy, sometimes itchy rash on the arms, legs and trunk.
- Contagious period
- During the cold-like phase, before the rash. Not once the rash appears.
- Treatment
- Rest, fluids and fever or pain relief. No antibiotics or vaccine.
- Watch out for
- Pregnancy, sickle cell disease and other blood disorders, and weak immunity.
When to get help
Call 911 or go to the ER
- A child with sickle cell disease or another blood disorder who becomes very pale, weak, breathless or drowsy
- Fever with a rash of tiny purple or red spots that do not fade when a glass is pressed on them
- A baby under 3 months with a temperature of 38 °C (100.4 °F) or higher
See a doctor within a day or two
- Pregnant and exposed to fifth disease, or pregnant with a rash or new joint pain: call your obstetric provider within a day or two
- Reduced fetal movements after a parvovirus infection in pregnancy
- Someone with a weakened immune system (chemotherapy, transplant, HIV) who has been exposed or is unusually tired and pale
Book a routine appointment
- Joint pain and swelling that lasts more than 2 to 3 weeks after the illness
- A rash that keeps returning for more than a month, or you are unsure what the rash is
Usually safe to manage at home
- A child with red cheeks and a lacy rash who is otherwise playing, eating and drinking normally
- Mild fever, runny nose and headache before the rash
- Mild itching of the body rash
What fifth disease is
Fifth disease gets its name from an old list of six common childhood rash illnesses. It was the fifth, after measles, scarlet fever, rubella and a now-abandoned "fourth disease". Roseola was sixth. Its medical name is erythema infectiosum.
It is caused by parvovirus B19, a human virus. It is not the same as the parvovirus that infects dogs and cats, and pets cannot catch it from people or give it to them. The virus infects cells in the bone marrow that make red blood cells and briefly stops red cell production for about a week. In healthy people this goes unnoticed. In people whose red cells already have a short life, it can cause severe anemia.
About half of adults have had it, often without knowing, and are immune for life.
Fifth disease stages and symptoms in children
- Cold-like phase (days 1 to 7 after symptoms start): low fever, runny nose, headache, sore throat and feeling generally unwell. Many children have very mild symptoms. This is when the virus spreads.
- Slapped cheek rash (about a week later): bright red, slightly raised rash on both cheeks, with paler skin around the mouth. The child usually feels well by now.
- Body rash (1 to 4 days later): a pink, lacy, net-like rash on the arms, legs, trunk and buttocks. It can itch.
- Recurring rash (up to several weeks): the lacy rash fades and returns, often brought out by heat, sunlight, a warm bath, exercise or stress. This is not a sign of reinfection or contagion.
Some people, especially adults, never get the facial rash. About 1 in 5 infections causes no symptoms at all.
Fifth disease in adults
Adults rarely get the slapped cheek look. More typical are:
- painful, swollen joints, usually on both sides, in the hands, wrists, knees and ankles
- flu-like symptoms
- a faint or lacy rash on the body, or none
Joint symptoms are more common in women. They usually settle in 1 to 3 weeks but can last months, and are sometimes mistaken for early rheumatoid arthritis. Blood tests for parvovirus can sort this out.
Is fifth disease contagious?
Yes, but only in the early, cold-like stage. The virus spreads through coughs, sneezes and saliva, and from mother to unborn baby. It can also spread through blood products. Symptoms appear 4 to 14 days after exposure, sometimes up to 21 days.
Once the slapped cheek rash appears, the person is generally no longer infectious. That is why children with the rash do not need to stay home if they feel well. People with a weak immune system or a blood disorder in aplastic crisis can stay contagious longer.
Fifth disease vs other rashes
| Fifth disease | Roseola | Measles | Scarlet fever | |
|---|---|---|---|---|
| Typical age | 5 to 15 years | 6 months to 2 years | Any age if unvaccinated | 5 to 15 years |
| Fever | Mild, before the rash | High for 3 to 5 days, then rash as fever ends | High, with rash | Fever with sore throat |
| Rash | Red cheeks, then lacy body rash | Pink spots on trunk | Blotchy, starts at hairline, spreads down | Sandpaper-like, red flush |
| How ill | Usually well when rash appears | Well once rash appears | Unwell, cough, red eyes | Sore throat, unwell |
| Treatment | Supportive | Supportive | Supportive; report to health authorities | Antibiotics |
See roseola, measles and scarlet fever for those illnesses.
Fifth disease in pregnancy
Most pregnant women who catch parvovirus B19 have healthy babies. The virus can, however, cross the placenta and infect the baby's red blood cell factories. In a small minority (under 5% of infected pregnancies), this causes severe fetal anemia, heart strain and fluid build-up called hydrops fetalis, or miscarriage. The risk is highest when infection happens in the first 20 weeks.
If you are pregnant and exposed:
- Tell your obstetric provider. A blood test shows whether you are already immune (most are) or newly infected.
- If you are newly infected, you will have serial ultrasounds, often every 1 to 2 weeks for 8 to 12 weeks, to check for fetal anemia.
- Severe fetal anemia can be treated with a blood transfusion to the baby in the womb, which is effective in most cases.
Pregnant teachers and childcare workers are not routinely advised to stay away from work during outbreaks, because people are most infectious before anyone knows they have it.
Who else is at risk?
- People with sickle cell disease, hereditary spherocytosis or other hemolytic anemias: the pause in red cell production can cause an aplastic crisis, a sudden, severe drop in hemoglobin that may need a blood transfusion.
- People with weakened immunity: the infection can persist and cause long-term anemia. It is treated with immunoglobulin (IVIG) infusions.
How fifth disease is diagnosed
The slapped cheek and lacy rash are usually distinctive enough for a doctor to diagnose fifth disease by looking. Blood tests for parvovirus antibodies (IgM for recent infection, IgG for past immunity) or viral DNA (PCR) are used in pregnancy, in adults with joint pain, and in people with blood disorders or weak immunity. A blood count checks for anemia.
Treatment and home care
There is no specific antiviral treatment, and antibiotics do not help.
- Rest and plenty of fluids.
- Acetaminophen (paracetamol) or ibuprofen for fever, headache and joint pain. Follow the label dose. Do not give aspirin to children or teenagers.
- An oral antihistamine or calamine lotion can ease itching.
- Avoid hot baths and strong sunlight if they make the rash flare.
Prevention
There is no vaccine. Handwashing, covering coughs and sneezes, and not sharing cups or utensils reduce spread. Excluding children with the rash does not help, because they are no longer contagious.
Frequently asked questions
Is fifth disease contagious?
Yes, during the first stage, when symptoms look like a mild cold. It spreads through coughs, sneezes and saliva. By the time the slapped cheek rash appears, a healthy person is usually no longer contagious, so children with the rash can go to school or daycare if they feel well.
How long does the fifth disease rash last?
The cheek rash usually fades in 2 to 4 days. The lacy body rash can come and go for 1 to 3 weeks, and sometimes longer, often flaring with heat, sunlight, exercise or a warm bath. These flares are harmless and are not a sign of being contagious.
Can adults get fifth disease?
Yes. Adults who were never infected as children can catch it, often from their own children. They are less likely to get the cheek rash and more likely to have painful, swollen joints in the hands, wrists, knees and ankles, which usually settle within a few weeks.
Is fifth disease dangerous in pregnancy?
Usually not. About half of pregnant women are already immune, and most babies of infected mothers are fine. In a small number of cases, especially in the first half of pregnancy, the virus causes severe fetal anemia or miscarriage. Pregnant women who are exposed should contact their provider for a blood test.
Can you get fifth disease twice?
It is very unlikely. One infection with parvovirus B19 normally gives lifelong immunity. A rash that keeps coming back for weeks after the illness is the same infection reacting to heat or sunlight, not a new one.
Is fifth disease the same as dog parvo?
No. Fifth disease is caused by human parvovirus B19. Dog and cat parvoviruses are different viruses that infect only animals. You cannot catch fifth disease from your pet, and your pet cannot catch it from you.
Sources
This guide was written from current patient and clinical guidance, including:
- CDC: About Parvovirus B19 and Fifth Disease
- American Academy of Pediatrics HealthyChildren.org: Fifth Disease
- NHS: Slapped cheek syndrome
- American College of Obstetricians and Gynecologists: Cytomegalovirus, Parvovirus B19, Varicella Zoster, and Toxoplasmosis in Pregnancy
- MedlinePlus: Fifth disease