Erythema Infectiosum: see symptoms, treatment, transmission

What is infectious erythema?

Infectious erythema, also known as Fifth Disease, is transmitted by the parvovirus B19 virus  through breathing, sneezing, coughing and secretions. It is more common in children and is characterized by facial rashes that resemble a slap in the face and spread throughout the body.

It spreads easily, but treatment is not difficult. It often disappears on its own and when treatment is needed, it is usually to reduce symptoms. It can be confused with rubella or measles . In pregnant women, it can cause miscarriage and fetal malformations.

It is known as the fifth disease because it was the fifth exanthematic disease (infectious diseases that cause spots on the skin) to be recognized clinically, after measles, scarlet fever , rubella and “Dukes disease”.

The latter, despite being called the fourth disease, was not confirmed as exanthematic and lost its classification, but the erythema continued with the name of the fifth disease.


Infectious erythema is caused by the parvovirus B19 virus. There are other variants of the virus, such as canine, feline, bovine and even porcine parvovirus, but B19 is the only one that affects only humans. So, if your dog catches parvovirus, you don’t have to worry about being infected or having your virus passed on to him.

During the spring, parvovirus usually appears and the disease is contagious even before symptoms appear. Once they appear, it is no longer transmissible.


Parvovirus is transmissible through secretions from the airways. Sneezing and coughing caused by other illnesses or reasons, speech and saliva, can carry the virus from one person to another. It is especially common in children and spreads easily, as it is transmissible before the clearest skin symptoms appear.

Thanks to its transmissibility, Fifth Disease can cause minor epidemics in certain areas and schools. The disease usually resolves in a few days and the treatment is to relieve the symptoms.

Although there is no vaccine, after curing, the patient acquires immunity.

Groups of risk


Infectious erythema guarantees immunity after its cure, but is easily contracted by those who did not have the disease. Studies show that 50 to 70% of adults have already had their fifth disease at some point in their lives, so they are immune. Children have had less time to contract it and contact with other children can cause it to become contaminated, creating immunity after that.

Who never had the disease

If you have never had the infectious erythema, contact with infected people can transmit the disease.


Most of the time, there are no symptoms, and even when there are, they can go unnoticed. However, when the disease is symptomatic, the patient may have:

Skin rashes

A characteristic symptom of exanthematous, infectious erythema has reddish rashes that start on the face, giving the appearance of a slap.

This symptom is present in only 15 to 20% of infected people. When it appears, it is usually 10 to 21 days after infection. In 1 to 4 days, the reddish spots pass to the trunk and limbs, which can affect a large part of the skin.

The symptom disappears within 10 days, but it can appear again in contact with very hot water, exposure to light, high temperatures and stress .

Paleness around the mouth

There may be, next to the rashes, a pallor around the lips. This is one of the characteristic symptoms of infectious erythema.

Headache and sore throat

The infection can cause mild headache in the patient. It is also possible that the throat presents pain, which can contribute to the confusion of the disease with a cold .


Itchy skin is common in patients with rashes.

Joint pain

Some patients, especially girls, may experience occasional joint pain. This symptom is more common in infected adults, but it can affect children. This symptom can last from a few days to months.

Low fever

Low fever (below 38ºC) is a symptom that can arise due to parvovirus infection, although it is rare. It is a flu- like symptom .

Discreet malaise

Like fever, mild malaise can be a sign of the flu, erythema or dozens of other illnesses.

How is infectious erythema diagnosed?

As only 20% of the cases present skin spots, many people never know that they have contracted the disease. However, when they appear, stains can cause concern. The general practitioner, pediatrician or dermatologist can diagnose the condition.

Physical exam

For the diagnosis of infectious erythema, skin rashes are examined on physical examination and the doctor can identify the disease through the characteristics of the spots.

Blood test

To eliminate doubts about the virus that is contaminating the person and there is no confusion with rubella or measles, the doctor may order a blood test to identify antibodies to the B19 virus.

Can infectious erythema be cured?

Yes, infectious erythema is curable . There is often no need to do anything and the body creates the antibodies needed to deal with the disease on its own.

Anemia and immune diseases

Patients with sickle cell anemia , thalassemia , HIV or other diseases that impair the immune system may have problems with eliminating the virus. Parvovirus B19 travels to the bone marrow and multiplies in the cells.

Usually, the speed of destruction of the virus is too fast for it to cause any problems, but in cases where it does not, it can cause severe anemia .

What is the treatment?

Treatments for infectious erythema are to reduce symptoms, which can be bothersome. It is usually a benign disease and does not cause any major problems.

When the patient complains of itching or joint pain, some medications, such as antihistamines and pain relievers, may be prescribed.

Anemia and immune diseases

In these cases, where there is a greater risk to the patient’s health, the patient can be treated with immunoglobulin to eliminate the virus.

Medicines for infectious erythema

The drugs recommended for the treatment of infectious erythema are mostly to relieve symptoms.


  • Loratadin ( Clarilerg )
  • Sodium dipyrone ( Novalgine )
  • Ibuprofen ( Advil )

Immunocompromised patients

  • Hizentra ( Immunoglobulin IV )


NEVER self-medicate or stop using a medication without first consulting a doctor. Only he will be able to tell which medication, dosage and duration of treatment is the most suitable for his specific case. The information contained in this website is only intended to inform, not in any way intended to replace the guidance of a specialist or serve as a recommendation for any type of treatment. Always follow the instructions on the package insert and, if symptoms persist, seek medical or pharmaceutical advice.


A complete cure of the infectious erythema can be expected after a few days or weeks. In most cases, it is not even possible to know that the disease is there. Only in cases where there is anemia or diseases of the immune system is it necessary to pay attention and make a more careful treatment, to prevent the disease from evolving into a severe anemia.


Severe anemia

If not treated in people with immunodeficiencies, infectious erythema leads to severe anemia. If there is knowledge of diseases that affect the immune system, such as sickle cell anemia or HIV, it is necessary to seek medical attention when symptoms are noticed.

Risks in pregnancy

Getting infectious erythema during pregnancy poses a risk to the fetus. The virus can pass from the mother to the baby, which can lead to fetal erythroblastosis , a type of severe anemia that affects fetuses, fetal hydrops ( generalized edema ) and heart failure, in addition to reducing the child’s oxygenation.

The virus is most dangerous for the fetus in the first half of pregnancy. In the first trimester, it can cause miscarriage, and in the second, it can lead to fetal hydrops. There are also risks of the baby being stillborn, which is when he dies before he is born.

Approximately 50% of adults have contracted infectious erythema before, and if this has happened to the mother, she is immune and will not pass the virus on to the baby. However, if this has not happened and the woman contracts the disease, the pregnancy must be closely monitored by the gynecologist.

How to prevent infectious erythema?

The prevention of this disease is difficult, since there is no vaccine and the infectious phase of it happens before the symptomatic – this when there are symptoms. Small localized epidemics of it occur in the spring, and the only way to avoid it is by not having contact with people, which makes its prevention difficult.

Wash hands

Although not guaranteed, the most effective way to prevent a fifth disease is to wash your child’s hands frequently and teach him or her how to do this. Contact with infected people can be unavoidable. This is especially necessary if there are immunodeficiencies and anemia.

Pregnant women should avoid contact with patients if they know of the infection and wash their hands frequently, but if they have already contracted infectious erythema at another stage in their life, worrying about the disease is unnecessary.

Infectious erythema is usually not a dangerous disease, it usually resolves in a short time and guarantees immunity for the rest of your life. It is more common in children and can cause localized epidemics. It represents risks only for pregnant women who never caught the disease and people with immunodeficiencies.